Hpsircuit winter 2014

HIGH PERFORMANCE

SIRCuit

“Merging COACHING with SPORT SCIENCE & MEDICINE” Winter 2014

Margarita Gorbounova Priscilla Lopes-Schliep

Also inside: Dr. GORD SLEIVERT YOUNG INVESTIGATOR AWARDS COLD WEATHER NUTRITION PREGNANCY and the High Performance Athlete NEW MUST Reads

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Editorial Welcome,

to the winter issue of the High Performance SIRCuit. We’re very excited about this issue because the High Performance SIRCuit is highlighting the winning sport research papers from the Dr. Gord Sleivert Young Investigator Awards, presented at the SPIN Conference in Calgary. Gord’s contributions to coaching and sport science in Canada were above and beyond. We are fortunate to have had Gord as a contributor to an earlier issue of the High Performance SIRCuit, as he wrote “Beat the Heat: Optimizing performance in a less than optimal environment”. The six leading edge research papers featured in this issue cover topics ranging from aerodynamics in speed skating to performance indicators in sprint swimming.

In particular, the winning research by Matt Jensen studies the impact of a carbohydrate mouth rinse on maximal voluntary force and neuromuscular output in a fatigued state. We encourage you to check out all the papers.

Athletes like Priscilla Lopes-Schliep are increasing our awareness and understanding of managing training

and pregnancy. The athletic successes achieved by athletes after pregnancy demonstrate the importance of managing the training and maximizing the recovery.

This section is an eye opener for coaches, support staff and athletes when it comes to enhancing women excelling in competitive sport.

And finally, the teams at SIRC and OTP are always looking for new articles and great new books to help our coaches expand their competitive intelligence. In this issue of the High Performance SIRCuit we have pulled together a new section called “Must Reads”. Check out the book reviews from the NSSMAC editorial team; find out what new articles on periodization and high performance psychology you should be reading; and see what new coaching books are now available.

Debra Gassewitz President & CEO SIRC

Thanks again for your valuable feedback; we hope you enjoy the High Performance SIRCuit.

Jon and Debra

Jon Kolb, PhD

Director, Sport Science, Medicine and Innovation Own the Podium

Subscribe to the High Performance SIRCuit here

Feedback

Editor

Contributing Editor

Content

Contributors

Debra Gassewitz Nancy Rebel Michelle Caron Joshua Karanja Trent Weir

Design

David Roberts Josyane Morin

Dr. Jon Kolb, OTP

Brian Benson Mathieu Charbonneau Bruce Craven Annick D’Auteuil Zach Ferraro Judy Goss Julie Gowans Heather Hynes Matt Jensen Matt Jordan Megan Kidston Leo Thornley Luciano Sebastian Tomaghelli Allan Wrigley

Special Thanks

Cara Thibault, OTP Paul Dorotich, OTP Margarita Gorbounova Priscilla Lopes-Schliep

Translation

Marcel Nadeau Alexandre Contreras

Photos Courtesy of:

Athletics Canada Canadian Olympic Committee Canadian Paralympic Committee Own The Podium SIRC Margarita Gorbounova Priscilla Lopes-Schliep

Sport Information Resource Centre (SIRC) is Canada’s national sport library, established over 40 years ago.

Mailing address: SIRC 180 rue Elgin Street, suite 1400 Ottawa, Ontario, Canada, K2P 2K3 Disclaimer: Author’s opinions expressed in the articles are not necessarily those of SIRCuit, its publisher, the Editor, or the Editorial Board. SIRC makes no representations or warranties whatsoever as to the accuracy, completeness or suitability for any purpose of the content.

Copyright © 2014 SIRC. All rights reserved.

No part of the publication may be reproduced, stored, transmitted, or disseminated, in any form, or by any means, without prior written permission from SIRC, to whom all requests to reproduce copyright material should be directed, in writing.

HP SIRCuit is partially funded by

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WHAT’S INSIDE The Gord Sleivert Young Investigator Awards Margarita Gorbounova

Pregnancy and the High Performance Athlete

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Dr. Gord Sleivert Young Investigator Awards

The Young Investigator Awards are a tribute to the sport science leadership that Dr. Sleivert shared with High Performance sport in Canada. The Award winners and finalists share their latest research findings.

Paralympic Athlete Profile: Margarita Gorbounova

An interview with Canadian Paranordic Skier Margarita Gorbounova gives insights into her mental preparation for competition and the Sochi Paralympic Winter Games.

Cold Weather Nutrition

Cold weather doesn’t stop sport. In fact many athletes embrace the cold as their season of competition.

But how does cold weather affect what athletes should put into their bodies?

Pregnancy and the High Performance Athlete

What is the current evidence and training recommendations for exercise during pregnancy for high performance athletes? Read about the science behind pregnancy and high performance athletes and watch the video interview with Canadian hurdler Priscilla Lopes-Schliep as she talks about adapting her training during her pregnancies.

Must Reads … Read, Learn, Excel

• IST Journal Club Reviews • Recommended Research Readings from SIRC & OTP • New Books @ SIRC www.sirc.ca

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The Gord Sleivert Young Investigator Awards Matt Jensen

Julie Gowans

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Carbohydrate Mouthrinse Counters Fatigue Related Strength Reduction

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Annick D’Auteuil

Examination of Voluntary Activation Ration in a Paralympic Swimmer with Hemiplegic Cerebral Palsy

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Modelling the Influence of Aerodynamics on Performance in Speed Skating

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Dr Gord Sleivert was a pioneer in the field of sport physiology and established innovative training systems and instruments. At the time of his passing in 2012, he was vice-president of Sport Performance at the Canadian Sport Centre Pacific helping establish and build the centre’s performance services team that helps power podium performances for Canadian athletes and coaches.

Established in 2013, The Dr. Gord Sleivert Young Investigator Awards (YIA) is a tribute to the sport science leadership that Dr. Sleivert shared with High Performance sport in Canada. The competition for the award is based on submissions from Canadian graduate students and/or young research/ innovators. The research submitted should have relevance to high performance sport

and/or exercise and its effect in the daily training environment and/or competition and/or athlete health and well-being.

An expert committee reviews all the submissions and selects the top six to make an oral presentation, to which three are awarded the YIA, which includes a plaque and $1,000 to support their continuation in High Performance sport research.

Mathieu Charbonneau

Megan Kidston

Luciano Sebastian Tomaghelli

FINALIST

FINALIST

FINALIST

Stroke-by-Stroke Acceleration Analysis of an Elite Swimmer

Time Course Changes of Muscle Temperature Following Warm Up in Cool Environments and the Effect of Passive Heating on Muscle Temperature and Performance

The use of a three dimensional accelerometer to asses continuous velocity during the start phase in the sport of luge: an instantaneous feedback tool.

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A CARBOHYDRATE MOUTH R ALTERATION IN NEUROM

Carbohydrate Mouthrinse Counters Fatigue Related Strength Reduction

Introduction

Authors: MJ JENSEN1, T STELLINGWERFF1, 2 and MD KLIMSTRA1

Short-term (<1-h) exercise performance appears unrelated to concentrations of muscle glycogen (Jeukendrup, 2004)

Affiliation: 1Exercise Science, University of Victoria, Victoria, Canada 2

Canadian Sport Institute, Victoria, Canada

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his study sought to determine whether carbohydrate (CHO) mouthrinse can improve maximal voluntary force (MVF) and enhance neuromuscular output in a fatigued state.

Previously, studies have shown that a CHO mouthrinse can improve performance for high intensity endurance exercise over 30 to 60min1. However, there are contradictory findings and no studies have examined the effect of CHO mouthrinse on maximal strength/power in a fatigued state. In a double-blind, cross-over design, 12 males initially performed 3x5sec MVF isometric knee extensions followed by a 50% MVF contraction until volitional exhaustion with quadriceps muscle activity measured via electromyography (EMG). Immediately after, either an 8% CHO maltodextrin (WASH), or noncaloric artificial sweetener (PLA) was mouthrinsed (not swallowed) for 10sec prior to 3x5sec final MVF. Compared to baseline measurements, WASH resulted in a significantly less attenuation in average peak force (8.5%) compared to PLA, which showed a 9.8% average decrease in peak force. First trial post fatiguing contraction the WASH had a 2.3% less attenuation (p<0.05) in peak force compared to PLA (205.6 ± 25.6 lb. vs. 193.7 ± 27.3 lb., respectively). EMG median frequency (MDF) for the vastus lateralis showed a greater reduction from baseline measurements for WASH vs. PLA, whereas the EMG root mean square (RMS) for the rectus femoris maintained non-fatigue values only during WASH. These changes in force and EMG were only noticed for the first two maximal bouts following the fatiguing contraction supporting a short lasting effect (~20 sec), which might be different than sub-maximal contraction protocols. In conclusion, this study provides evidence that CHO mouthrinse can acutely increase maximal strength (~2.3%) following a fatiguing contraction potentially through modifications in a neuromuscular strategy. These results suggest a time sensitive central mechanism of performance enhancement through the use of a CHO mouthrinse. ∆

The acute performance enhancing effect of CHO intake during high-intensity exercise situations of <1-h are probably based on alternate mechanism(s) It is theorized that CHO ingestion may impact performance through central/cognitive effects (Rollo, 2011) CHO mouthrinse has been shown to improve performance for high-intensity endurance exercise( approx. 1-h) (Carter 2004), however, has been shown to have no affect on maximal strength/power type exercise (Painelli et al. 2011) The effect of CHO mouthrinse on maximal strength/power in a fatigued state has not been examined The fatigued state of an individual can be measured indirectly through modifications in muscle activity inherent in the signal properties of electromyography (EMG, (De Luca, 1997)

Purpose Investigate the effect of CHO mouthrinse during a maximal isometric knee extensor contraction in an acute fatigued state on: Muscular force production (performance outcome) Neuromuscular output

Methods 12 Competitively active healthy male participants recruited to volunteer in a doubleblind, cross-over experimental design Table 1. Description of participants (mean ±SD)

Age (years) 26.7 ± 6.7

Weight (kg) 78.2 ± 5.5

Height (cm) 184.9 ± 6.1

EMG was collected from 3 leg muscles; Vastus Lateralis, Vastus Medialis and Rectus Femoris Carbohydrate mouthrinse (WASH) consisting 8% maltodextrin or non-caloric artificial sweetener (PLA) were rinsed for 10 seconds after fatiguing contraction Fatiguing contraction was performed to volitional exhaustion during an maximal voluntary isometric leg extension (MVF) Root means square(RMS), and median frequency (MDF) was calculated using a 300ms interval around maximum force for each MVF. EMG frequency content was determined by using discrete Fast Fourier Transform method Average force was calculated using last 3s of each MVF

Te s t i n g P r o t o c o l

For references, click here

Mouthrinse

Fatigue Task

Baseline Measurements

MVF

MVF

Rest

Post-Fatigue

MVF

MVF

MVF

MVF

Fatiguing Contraction: 50% MVF 60s

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60s

300s

30s

10s

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RINSE RESULTS IN REDUCED DEPRESSION OF MAXIMAL FORCE AND MUSCULAR STRATEGY FOLLOWING A FATIGUING CONTRACTION 1

Matt Jensen1, Trent Stellingwerff1,2, Marc Klimstra1

School of Exercise Science, Physical and Health Education, University of Victoria, BC 2 Canadian Sport Institute - Pacific, Victoria, BC

Results % Difference Attenuation 2.3% 1.0% 0.6%

(A) peak force of pre- and post-fatigue MVFs, (B) peak force decrease (%) from baseline. † (PLA) ‡ (WASH) represent significantly decreased force production in post-fatigue MVFs compared to pre-fatigue, P < 0.05. * Significantly different from PLA for corresponding MVF, P < 0.05. Data are presented as means ± SE.

% Difference Attenuation 3.3% 1.9% 1.0%

The effect of CHO mouthrinse on (A) average force of pre- and post-fatigue MVF, (B) average force decrease (%) from baseline. † (PLA) ‡ (WASH) represents significantly decreased average force production in post-fatigue MVFs compared to prefatigue, P < 0.05. * Significantly different from PLA for corresponding MVF, P < 0.05. Data are presented as means ± SE.

Group EMG RMS amplitude for pre- and post-fatigue MVFs. Data are presented as means ± SE. § Significance for greater increase in RMS amplitude in the WASH group for the first post-fatigue MVF, P < 0.05.

Group EMG Median Frequency for pre- and post-fatigue MVFs. Data are presented as means ± SE. † (PLA) ‡ (WASH) represent significantly decreased Median Frequency in post-fatigue MVFs compared to pre-fatigue, P < 0.05. * Significantly greater decrease in Median Frequency in the WASH group for the first post-fatigue MVF in the Vastus Lateralis, P < 0.05.

Conclusions Changes in force and EMG were only noticed for the first two maximal bouts following the fatiguing contraction supporting a short lasting effect (~20sec) This evidence shows that CHO mouthrinse can cause an acute, time sensitive increase in maximal strength (~3%) following a fatiguing contraction Performance enhancement may potentially be caused by a central mechanism References Carter, JM, Jeukendrup, AE, Jones, DA (2004). Med Sci Sports Exerc; 36(12): 2107-11.

De Luca, C (1997). J Appl Biomech; 13(2): 135-63 Juekendrup, AE (2004). Nutrition; 20(7-8): 669-77.

Painelli, VS et al (2010). Scand J Med Sci Sports; 111(9): 2381-6.

Rollo, IW (2011). Sports Med; 41(6):449-61.

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Julie Gowans

EXAMINATION OF VOLUNTARY ACTIVATION RATION IN A PARALYMPIC SWIMMER WITH HEMIPLEGIC CEREBRAL PALSY Authors Julie GOWANS1, Jared R FLETCHER1, 2 and Brian R MACINTOSH2 Affiliation 1 Canadian Sport Institute Calgary, Calgary, AB 2 Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, AB

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erebral Palsy (CP) is associated with decrements in overall strength. It has been reported that the underlying mechanism of muscle weakness is due to the inability to fully activate all available motor neurons and in part, by increased antagonist coactivation. In order to optimally prescribe training programs for athletes with CP, it is important to understand what, if any motor impairments are present between affected and unaffected limbs. Therefore, the purpose of this case study was to determine the extent of motor unit impairment, between limbs in an elite female Paralympic swimmer. A secondary purpose was to determine the in vivo force-velocity properties of the plantarflexors in the CP-affected and non-affected lower limb, using isokinetic dynamometry.

One elite female Paralympic swimmer (19 years, 162.4 cm, 58.7 kg) diagnosed with hemiplegic CP was tested using an isokinetic dynamomter (Biodex System 3). Maximal activation of the right tibialis anterior (TA) and medial gastrocnemius (MG) muscles was determined by surface EMG while the

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athlete was in the prone position, during a maximal voluntary isometric contraction (MVIC). Muscle activation of these muscles was measured using electromyography and the extent of voluntary activation (VAR) of the MG was determined determined using the interpolated twitch technique during a maximal voluntary isometric contraction.

Following this, the athlete completed maximal voluntary isokinetic contractions on the non-affected leg at speeds ranging from 30 to 500 degrees•sec-1. The speeds were selected in a randomized order. The entire protocol was repeated on the affected leg.

Force-velocity data were fitted to the Hill equation.

Maximal isometric torque was higher in the affected leg when compared to the nonaffected leg (85 Nm vs. 76 Nm). In the nonaffected limb, VAR was 84.9% compared to 97.3% in the affected leg. Isokinetic torque was higher in the non-affected compared to the affected leg at every velocity up to and including 240 degrees•sec-1. In contrast, at 300 and 500 degrees•sec-1 torque was higher in the left leg (7.2 Nm vs. 11.0 Nm

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and 2.1Nm vs. 6.9Nm, respectively). The Co-activation ratio (MG RMS:TA RMS) measured during the isokinetic trials was not different between limbs (range between 7.5 and 10.1). There was no limb x velocity effect of activation (p>0.05, range: 88-100%).

This case study demonstrated a decrement in isokinetic torque at moderate speeds, and a relative maintenance of torque at high speeds in the affected leg. These differences could not be attributed to a lower VAR in the affected MG. Combined with the knowledge that VAR is lower in the unaffected leg, we suggest that single leg strength training exercises may be beneficial to include in a strength training program for athletes with hemiplegic CP in order to account for differences in VAR and absolute strength between legs. Future research will examine potential differences between limbs in MG muscle architecture and VAR during dynamic contractions to attempt to elucidate potential reasons for maintenance of torque at high velocities in the affected leg. ∆

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Annick D’Auteuil

MODELLING THE INFLUENCE OF AERODYNAMICS ON PERFORMANCE IN SPEED SKATING

Authors Annick D’AUTEUIL and Guy L. LAROSE Affiliation National Research Council Canada, Ottawa, ON,

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or sports where travelling speed is significant, a large contributor to the resistance to motion of an athlete is the aerodynamic drag. Through wind-tunnel tests, the aerodynamic drag force can be measured and solutions can be found to decrease the drag force and to increase the speed of the athlete or, to deploy less energy to maintain the same speed.

The drag force can be reduced through optimization of the equipment used by an athlete. Results of wind tunnel tests generally provide the percentage of reduction of the drag area, CDA. Naturally, the athletes and coaches are interested in knowing the race time savings corresponding to a reduction of CDA. To answer this question, an evaluation of all the forces that are acting on the athlete in a race event has to be carried out. This evaluation allows a correlation between time and drag area.

A software package including an analytical model, an equation-solver program, and a graphical user interface has been developed to predict race times for a long track speed

skater. A more accurate description of the drag force was integrated in the power equation to obtain more representative predictions of race times of a skater.

Simple models of the drag force lead to erroneous race time predictions as this factor contributes significantly to the total power dissipated. The speed dependence as well as body dimensions and body position were taken into account in the definition of the drag area1. Also, the effect of atmospheric pressure and altitude were considered in the definition of the air density2. Variation of drag area with wind speed, obtained from wind tunnel tests for different positions of a speed skater, can be combined and input in the program to predict race times. The program has been developed to predict race times of an athlete competing with a variety of external conditions, not just aerodynamics.

The power equation of a speed skater includes the power production, the power dissipation and the rate of change of the mechanical energy of the body. An expression for power production and values for power dissipation related to ice friction

losses for a speed skater3,4 were obtained from the published literature. The equations were initially used to solve the global power equation. An improvement to the expression of the power production was made to include the influence of gender. A graphical user interface was developed to allow the user to input the mass, the race distance, the gender, the location of the race, the atmospheric pressure level, the ice friction coefficient, the variation of drag area with speed, a nominal reduction of drag area, and the skill level of the skater.

Validation of time predicted with the current model, for different race distances and gender, was carried out by comparing intermediate and final times recorded during World Cup races in 2011-2012 for events in different cities and for different skill levels of skaters5. The comparison of the actual and predicted final times was within 0.2% for all the race distances. Results from the simulation indicated that for a 1500 m race, a reduction of 5% of the CDA corresponds to a time saving of 1.7 seconds for women, and 1.5 seconds for men, or 1.5% of race time. ∆

For references, click here

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Finalists Mathieu Charbonneau CHANGES IN KEY PERFORMANCE INDICATORS DURING 100 m SPRINT SWIMMING: Case study of an elite sprinter Authors

Mathieu CHARBONNEAU, Benoit LUSSIER, and Francois BILLAUT Affiliation Institut national du sport du Québec, Montréal, QC Purpose: Successful swimmers manage hydrodynamic forces to promote propulsion by moving segments and to reduce resistance by adopting streamline postures and optimal gesture1. Stroke-by-stroke analysis of the acceleration signal is sensitive to detect subtle modifications of acceleration amplitude, timing and inter-limb coordination within a single 100-m freestyle swimming trial (see companion paper Lussier et al. 2013).

These variables are influenced by fatigue and the athlete’s swimming strategy2. This study aimed to describe and compare the strategy and motor coordination of an elite sprint swimmer in two different swimming sessions using accelerometry data.

Methods: An inertial sensor (Nanotrak, Catapult, Australia) was secured to lumbar spine in the middle of a line between posterosuperior iliac spines. 3-D accelerations and 3-axis angular speed

were sampled at 100Hz. Two all-out 100m swim trials were analysed from an elite sprint swimmer of the National Training Center in Montréal. The first swim was in a fatigue state and the second was done days apart in a fresh state. Raw signal was divided into swimming phases3. Automated processing and data reduction routine was applied to whole race’s signal (see Lussier et al. 2013). The following variables were calculated for every stroke: stroke rate (SR, stroke/min), stroke length (SL, m/stroke), forward efficiency (RMSE between forward acceleration and resultant acceleration), an index of coordination for the arms (IoC_arms, latency between each effective stroke), and an IoC_arm/leg (timing between each effective arm stroke and the closest effective kick).

Main results: The second trial (fresh state) was 2.7s faster. To achieve this performance,

the swimmer performed 2 more underwater kicks and kept SR, SL and RMSE more stable throughout the whole swim. Interlimb coordination changed : IoC_arm/leg was enhanced with kick contributing shortly before opposite hand pull, and IoC_arms displayed a shorter latency.

Conclusion: This stroke-by-stroke analysis allows the detection and quantification of multiple sensitive key performance indicators to precisely examine 100-m sprint swimming in an international level athlete. Changes in locomotor patterns and coordination were concomitant to performance enhancement across the 2 trials. Findings were discussed within the Integrated Support Team to refine training and race strategy. Acceleration data therefore prove paramount to objectively quantify technique and efficiency associated with swimming performance. ∆ For references, click here

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Finalists Megan Kidston TIME COURSE CHANGES OF MUSCLE TEMPERATURE FOLLOWING WARM UP IN COOL ENVIRONMENTS AND THE EFFECTS OF PASSIVE HEATING ON MUSCLE TEMPERATURE AND PERFORMANCE Authors

M.J. KIDSTON1, 2, L.A. STUART-HILL1 & B.C. SPORER1, 2 Affiliation 1 School of Exercise Science, Physical & Health Education, University of Victoria, Victoria, BC 2

Canadian Sport Institute Pacific, Victoria, BC

The purpose of this study was to determine the effects of active warm up (WU) and passive heating (HP) following WU on muscle temperature and performance in cool (~10°C) environments. Eight male recreational athletes (29±5 y) with a minimum relative mean VO2peak score of 50mL∙kg1 ∙min-1 (58.0±6.3 mL∙kg-1∙min-1) completed two 60-minute sessions in an environmental chamber (9.77˚C, 71%RH). Following 15 minutes of standardized WU on a cycle ergometer, heat was applied to the legs during 30 minutes of inactivity using custom designed heated pants in HP but not in control (CON). Core (Tc), skin (Tsk) and muscle (Tm) temperature, heart rate (HR), and thermal comfort (TC) and sensation (TS) were monitored at 5 minute intervals throughout test sessions. Muscle performance was assessed using countermovement vertical

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jump (VJ) height measured pre- and postWU and at 10, 20, and 30 minutes post-WU. A 45 second Wingate anaerobic test (WAnT) was performed following 30 minutes of inactivity post-WU and was used to assess anaerobic capacity, power, and fatigue. WU resulted in similar and significant increases in Tm (3.8°C) and VJ (17% improvement) from baseline to post-WU between conditions (p<0.001). Tsk showed a difference between HP and CON prior to, during, and at the end of WU (p<0.05). Following WU, Tm during CON fell immediately and consistently during 30 minutes of inactivity (p<0.01). In contrast, Tm was maintained for 20 minutes post-WU and was significantly higher at 30 minutes post-WU than CON by 2.3°C (p<0.05). This maintenance in Tm during HP was associated with a higher average power output calculated from 45 second

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WAnT (p<0.05). No differences were seen in VJ performance, TC, or TS following WU (p<0.05). In conclusions, these data show that a substantial cycling effort (15 minutes at 70% HRpeak) was needed to significantly increase Tm and improve subsequent muscle performance, as measured by VJ. These data also show that passive heating can be used to maintain Tm for up to 30 minutes following an active warm up and may enhance muscle performance in certain power activities in cool environments (~10°C). After 30 minutes of inactivity, with or without HP, jump height remained 3-5% higher than baseline, highlighting the importance of performing a well-timed WU of sufficient duration and intensity prior to performance even when inevitable delays may occur. ∆

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Finalists Luciano Sebastian Tomaghelli THE USE OF A THREE DIMENSIONAL ACCELEROMETER TO ASSES CONTINUOUS VELOCITY DURING THE START PHASE IN THE SPORT OF LUGE: AN INSTANTANEOUS FEEDBACK TOOL. Authors

Luciano TOMAGHELLI1, 2, John HORTON1, Larry KATZ2, Jay WOROBERTS2 & Pro STERGIOU1 Affiliation 1 Canadian Sport Institute Calgary, AB, 2University of Calgary, AB Purpose: Accelerometers have been widely used in sports sciences for different purposes: physical testing1,2,3,4, assessment of human gait5,6, determining swimming velocity7,8,9 and measuring sports intensity and performance10,11. It is common knowledge among luge athletes and coaches that a good start is vital for a successful performance.

Research has shown that in the sport of Luge, 55% of the variance in final time is explained by the start time12. The aim of this study is to validate the use of three-dimensional accelerometers to obtain continuous velocity information during luge starts and to use this technology to provide instant feedback to athletes with regards to their start performance.

Methods: A three dimensional wireless accelerometer (G-Link LXRS, Microstrain) was attached with Velcro under the centre of the luge sled. Nine athletes (national or development) participated in this study.

Acceleration data were collected (sampling rate 1024 Hz, for 15 seconds) while the athletes performed their starts during a technical training session. Athletes were

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asked to remain steady for at least 3 seconds when data collection began before performing the start to assure accuracy in the data analysis process. Also, time data were collected with 3 sets of Brower timing lights situated at 1.5, 3.5 and 10.5 meters from the start handles.

After the athletes performed 3 trials, the data from the accelerometer were imported wirelessly to a laptop. For data processing, the channel of data corresponding to the horizontal acceleration was integrated with a custom made computer program (Matlab version 7.10.0499, The Mathworks) in order to obtain continuous velocity of the sled.

Results: A difference of 0.7-7.5% was found between the average velocity as calculated from the accelerometer and the timing lights.

Larger differences were found between the velocity measurements of the accelerometer and the timing lights when athletes do not remain steady for at least the 3 seconds recommended before performing the start.

However, if the athlete remained steady for at least 3 seconds, only a 2% difference in the average velocity is found between the two methods.

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Several performance indicators could be indentified from the continuous velocity curve graph as calculated from the horizontal acceleration data. These included the slope of the velocity curve when releasing from the handles (how steep is the curve), the frequency between the paddles (how fast the athlete is cycling in the paddles), and other potential inefficiencies during the paddles (acceleration/deceleration profiles). For example, some athletes show a decrease in the velocity between the contact with the ice and release during the paddles while other athletes increase their velocity significantly from contact to release, thus affecting start performance time.

Conclusion: Accelerometers appear to be a valid method which can be used to asses continuous velocity during luge starts and also can be used to provide detailed feedback to the athletes on their start performance which cannot be achieved using conventional timing lights.

Future research should focus on identifying key start performance indicators and using accelerometer technology not only in training but on competition tracks for the assessment of starts and other aspects of the race. ∆ For references, click here

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Paralympic Athlete Profile Margarita Gorbounova Sport: Para-Nordic Skiing Height: 161 cm Date of Birth: 1 July 1984 Birth Place: St. Petersburg, Russia Residence: Ottawa, ON Twitter: @MGorbounova Blog: paranordicskier.blogspot.ca Team Canada: paralympic.ca/athletes/42606 Nickname: Rita

Career Highlights Vancouver 2010 Paralympic Winter Games • Cross Country Skiing Women’s 1 km Sprint visually impaired – 9th place Women’s 15 km visually impaired – 7th place Women’s 5 km visually impaired – 12th place • Biathlon Women’s 3 km Pursuit visually impaired – 11th place

Also check out Margarita Gorbounova has history on her side in Sochi Margarita Gorbounova mulling double ski-biathlon duty at Paralympics

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Q&A

with

Margarita Gorbounova

An interview with Canadian Paranordic Skier Margarita Gorbounova gives insights into her mental preparation for competition and the Sochi Paralympic Winter Games.

Q How do you mentally prepare for

competition?

A I prepare for competition by going over my

Q During the Vancouver Games, what

worked best to mentally prepare for the games and what adjustments have you made in preparation for Sochi?

race course the day before and segmenting it (dividing it into pieces based on location A Since Vancouver, I have learned to use and terrain) with my guide. Then we go over certain words in the morning before a race the course together and write a race plan that allow me to calm down if I start to get indicating which technique we will use on nervous or something upsets me. each segment etc. I go over the plan in my head before I fall asleep the night before the Q Do you have any superstitions or a routine you do before a race? race. On race day, I use certain words that calm me down and help me deal with nerves A No, I don’t have any superstitions. Before and follow my usual prep routine. my races I like to get a nice long warmup with lots of sprints. I find that if I keep Q During the Vancouver Games, did you moving it helps me stay more relaxed and have a mental routine before competition distracts me from being nervous. and how did it help you deal with nerves, before racing?

A At the Vancouver Games, I followed my

usual routine of developing a race plan with my guide and going over it before the race.

It was also great to have my family there watching. It gave me extra confidence.

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Q What are some of the things you have

done to stay focused on your goals during a difficult mental phase in preparation for Sochi?

A During a difficult mental phase, I would just

try to refocus and get my thoughts to go in a more positive direction. I would focus more on day-to-day training and the progress I am making than on whatever is making me doubt myself.

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Q You were at home at the 2010 Vancouver

Games, how is it different in terms of pressure, staying focused and controlling your emotions, as you will be in your country of birth, Russia, for the 2014 Sochi Games?

A Vancouver was an amazing experience.

To be part of Team Canada at the home games gave me such an awesome feeling.

The Sochi Games won’t be the same in that sense. Even though Russia is my country of birth, it is no longer my home and I am part of Team Canada, so I don’t think I will feel more pressure or be more emotional in Sochi.

Q What suggestions would you give

others athletes on the aspects of mental preparation that you think is important or has worked very well for you?

A I would tell other athletes to try and not

let things, such as a bad performance in one competition, get to them, to maintain a positive attitude and to always race their own race and not worry about others.

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Cold Weather Nutrition

by Nancy Rebel, SIRC

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old weather doesn’t stop sport.

Rather many athletes embrace the cold as their season of competition. And while we all know that proper nutrition fuels performance, how does cold weather affect what athletes should put into their bodies?

The term ‘winter sport’ generally refers to those sport commonly played during the winter season on snow or ice. These sports generally include, but are not limited to, Olympic sports such as figure skating, ice hockey, speed skating, cross-country skiing, ski jumping, freestyle and alpine skiing, snowboarding, biathlon and curling. Each of these sports incorporates different physiological stresses on the athlete and therefore requires specific modifications to meet energy requirements.

What does the science tell us about the particular factors of cold environments that affect nutritional requirements for athletes?

The natural assumption is that cold weather itself brings on an increased energy need, however, the actual reality is that it is not the cold temperature, but the drop in body temperature and the resulting act of shivering that causes extra calories to be burned. It is the natural reaction of an individual to increase their activity - shivering, moving to stay warm and

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the like – that depending on its vigor begins to deplete muscle glycogen stores and drains your energy. It is also the additional weight of extra layers of clothing that may also cause increased energy expenditure. Additionally, you burn extra calories to warm and humidify the air you are breathing in cold weather. All these factors in any combination may contribute to the need for increased nutritional intake to balance the energy expended.

Does altitude play a role in energy needs?

There are a number of winter sports where altitude comes into play for training and/ or competition. Altitude and cold weather can affect fluid loss for athletes. Cool, dry conditions can increase water losses during breathing. The harder the breathing, the higher the risk of fluid loss. The cold weather athlete should be mindful in consistently checking fluid levels in order to balance it with exertion. Evidence also suggests that there is an increase in carbohydrate use during exertion at altitude so athletes need to incorporate strategies in their training plans to replace these stores. Altitude also may induce an increase in oxidative damage and trigger an adaptive response to increase red blood cell production. Athletes should make a conscious effort to include foods that are high in antioxidants and iron.

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Are there special considerations for cold weather hydration?

Research suggests that many winter athletes do not hydrate to an appropriate level, which affects performance. Cold weather masks the natural inclination to feel thirsty, which means athletes are often not drinking enough to balance fluids lost through sweat.

Cold weather athletes, especially those who perform at higher altitudes as mentioned earlier, also need to be aware of fluid loss occurring through the process of warming and humidifying the air that they breathe. Thus when you “see your breath” you are seeing fluid loss. Cold weather also means more layers of clothing. Dressing in layers reduces fluid loss due to sweat by allowing for continual adjustment of body temperature by adding or removing layers. But with the added layering of clothing sometimes athletes are inclined to drink less fluids in order to reduce the “hassle” of needing to use the washroom. Hydration needs to account for all these elements. When you are replacing these fluids, you want to make sure that your drink is not icy or even cold as this will contribute to the chilling effect of the air temperature. Rather the suggestion is to carry an insulated water bottle filled with a hot sports drink covered with a wool sock to help retain the heat.

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“

...you want to make sure that your drink is not icy or even cold as this will contribute to the chilling effect of the air temperature. Rather the suggestion is to carry an insulated water bottle filled with a hot sports drink covered with a wool sock to help retain the heat.

When should athletes be eating?

Pre-exercise fueling is all about generating body heat. Fueling before you exercise produces a warming effect known as thermogenesis.

Your body generates about 10% more heat 30-60 minutes after you’ve eaten compared to having an empty stomach. Food in this context not only provides fuel for exertion, but also provides this added “warming” effect to combat colder temperatures. During exercise you might find yourself feeling chilled. A drop in body temperature often triggers a natural “hunger” response. It is the body’s way of replenishing fuel to burn for warmth. Athletes should always carry that emergency stash of food not only to feed the furnace, but due to the higher risk of accidents prevalent in the nature of winter sport. If an athlete is caught out on the slopes or trails unexpectedly, having these emergency stores will help maintain warmth until they can get back home. Recovery fueling is another key factor, with the focus on replacing glycogen stores which can be reduced by 50% on a typical training day. Heavy exertion during training and especially during competition can further deplete glycogen stores. These stores should be replaced as quickly as possible after competition or high-intensity training.

”

Are there special considerations for high performance athletes?

Many additional factors also come in to play when fueling high performance cold weather athletes: cold weather brings cold and flu season, training and competition schedules become more intense, foreign travel for training and competition limit access to the foods athletes are accustomed to, training may occur in remote locations and access to food and timing of fueling becomes more challenging, altitude and climate changes occur, fruits and vegetables are often less readily available or cost more, and food allergies or special requirements may be harder to incorporate on the road. All these factors must be taken into consideration and planned for in advance.

So what does this mean for athletes training and competing in colder weather?

In general the basic nutritional needs are similar to most any athlete. However, the cold weather athlete must also take into consideration the extra concerns of body temperature and its reaction to environmental temperature and adapt to the additional energy expenditure used to compensate for these differences. ∆ For references, click here

High Carbohydrate Pre-event Meal Suggestions Breakfast • Cereal and milk, fruit • Toast and jam/honey • Pancakes and syrup • Fruit yogurt • Baked beans or spaghetti on toast • Liquid meal supplement or smoothie

From the IST Journal Club Do different sports have different requirements?

NSSMAC editorial team member, Heather Hynes, reviews an article that speaks to this question.

Nutrition for Winter Sports.

Meyer N, Manore M, Helle C. Journal Of Sports Sciences. December 2, 2011;29:S127-S136.

Reviewed by Heather Hynes This review article summarizes many of the unique nutritional challenges for winter sport athletes. The authors highlight the importance of nutritional planning in preparation for major winter events; therefore it’s an ideal time to revisit these points in preparation for the Winter Olympic and Paralympic Games. From altitude training to varying environmental conditions (temperature, humidity), nutritional concerns need to be addressed and strategies should be put into place to help our high performance athletes deal with their sporting environment and training/competition schedules. Many practical recommendations are made for athletes training at altitude in regards to energy, macronutrient and fluids needs. Key micronutrients for winter sport athletes are also discussed; both iron and vitamin D status should be monitored on an ongoing basis and supplements may be needed. Key recovery points are reviewed; the macronutrient needs of high performance athletes should be planned into the recovery practice at the sport venue. The article concludes by addressing the importance of competition planning to ensure adequate fuel and fluid availability at the competition site. ∆

Lunch/Dinner • Rice (including risotto, paella, etc) • Pasta and light sauce • Bread (rolls and sandwiches) • Fruit and fruit-based desserts • Rice Pudding Source: IOC. Special Needs for Winter Sports. In Nutrition for Athletes.

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meet priscilla a mother AND athlete

SPORT: ATHLETICS - HURDLES HEIGHT: 163 CM

PRISCILLA LOPES-SCHLIEP

DATE OF BIRTH: AUGUST 26, 1982 BIRTH PLACE: SCARBOROUGH, ONTARIO RESIDENCE: WHITBY, ONTARIO

A

CLUB: ELITE EDGE COACH: ANTHONY MCCLEARY

t one time, a woman’s pregnancy would mean the end of her athletic career, but no longer.

The number of elite athletes who are managing to balance an athletic career and a family is growing. Olympic bronze medal hurdler Priscilla Lopes-Schliep, is up to the challenge with baby number two born in August of 2013.

In this video interview (see page 19) “Motherhood and Athletics”, by Own The Podium with Priscilla LopesSchliep, Priscilla speaks about the lessons learned, the importance of a good support team and the message she wants to pass on to her girls.

Ultimately, Priscilla has redefined her success.

TWITTER: @GOPRISCILLA WEBSITE: WWW.GOPRISCILLA.COM TEAM CANADA: OLYMPIC.CA/TEAM-CANADA/PRISCILLA-LOPES/

CAREER HIGHLIGHTS

2012

NTL#3-Donovan Bailey Invitational, 100 m hurdles: 1st place

2010

Belgacom Memorial Van Damme, 100 m hurdles: 1st place Aviva London Grand Prix, 100 m hurdles: 1st place

2009

Canadian Track and Field Championships, 100 metre hurdles: 2nd place World Championships in Athletics, 100 metre hurdles: 2nd place

2008

Canadian Track and Field Championships, 100 metre hurdles: 1st place Beijing Olympic Games, 100-metre hurdles: 3rd place

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Mentally ready to go; physically had to wait for body to catch up.

”

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Priscilla Lopes-Schliep

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“

Do your best, what you’re capable of.

That’s what counts in the long run. No regrets.

”

Priscilla Lopes-Schliep

Highlights Training during and post pregnancy was important for both her physical and mental state. She had to be aware of physical restrictions, such as she couldn’t hurdle, squat or do weights. Sometimes the biggest challenge was the athlete herself and her desire to train at the same intensity as she was familiar with, however, her coach would need to remind her that she had just had a baby and needed to adjust her training. Her comments in the interview reflect the conflict between thinking she was mentally capable and yet dealing with what her body was physically able to handle.

The support team that includes her husband, grandparents, coaches, and IST were critical in helping her to keep training and to keep competing. While she experienced gestational diabetes during her pregnancy, she was able to control it with a proper diet. Her ISTs helped her regain her focus and training schedule post-partum. Her family played a key role in helping develop a home life and athletic career; to the point that she sees how having children has “made her a better athlete”.

One year after Priscilla’s first child, she reflects upon competing at Nationals. She was the fastest woman hurdler in Canada, but disaster struck, she hit a hurdle and didn’t make the national team going to the London Olympics. While she could have stormed off the track, she thought “These kids come out here to watch us….”. What you do and say affects others. And with that self-awareness instinct, she equally applies skills developed through her athletic training to motherhood. Whether it’s goal setting, adhering to rules or respecting your coach, she applies the similar principles to raising her girls. She often says she wants to be an example for her girls. She wants them to know that their mom set goals, never gave up and became the best she could be.

Motherhood and Athletics video interview with Priscilla Lopes-Schliep

www.sirc.ca www.sirc.ca

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Exercise during pregnancy for elite athletes: Current evidence & training recommendations

By Zach Ferraro PhD, CSEP-CEP

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renatal life is recognized as a critical period where vital physiological processes may be permanently transformed leading to altered susceptibility to disease risk later in life1. Accordingly, fetal adaptive responses to the maternal environment, including the in utero effect of a physically active pregnancy, may influence the longterm health and wellbeing of the developing child. However, is there potentially lifelong benefit of maternal exercise on fetal health? And, can you exercise during pregnancy without harming yourself or your

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developing child? This paper will attempt to answer these questions by providing an overview of maternal exercise physiology and highlight the effect of physical activity (PA) on maternal-fetal outcomes. Lastly, training recommendations will be made that align with the joint position statement put forward by the Society of Obstetricians and Gynecologists of Canada and the Canadian Society for Exercise Physiology (SOGCCSEP Position Stand)2.

Pregnancy is a unique state in which women are highly motivated to change

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behaviour3. Nonetheless, despite this ‘teachable moment’, many women are unaware of what constitutes ‘safe and effective’ exercise practice and have difficulty overcoming common barriers to participation.

Consequently, they do not fully benefit from PA during pregnancy4,5. In addition, health care providers may fail to recognize the benefits PA during pregnancy and thus do not make proper use of available screening tools that encourage participation such as the ‘Physical Activity Readiness Medical Exam for Pregnancy’ (i.e., the PARmed-X)6.

This user-friendly, pregnancy-specific tool

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Key Points

Dr. Zach Ferraro MSc, PhD, CSEPCEP

• Pregnancy is a critical period of body weight regulation for mom and baby where excessive gestational weight gain (GWG) is common, contributes to poor maternalfetal outcomes and may hinder return to play and competition • All coaches and care providers must use the PARmed-X to appropriately screen pregnant athletes prior to participation in physical activity or exercise training • Goal setting for pregnant women should include maintenance of aerobic fitness without trying to reach peak fitness or training for an athletic competition. Strength-conditioning exercises are encouraged; choose activities that will minimize the risk of loss of balance and fetal trauma • Maternal physical activity helps limit GWG to the recommended targets, reduces risk of developing Gestational diabetes mellitus (GDM), preeclampsia and abnormal fetal growth; adverse outcomes are not increased for active pregnant women • Novel research suggests the developing child is able to adapt to the physiological stress imposed by maternal exercise via structural and functional changes at the level of the placenta to help ensure fuel and oxygen delivery to the fetus in the presence of adequate nutrition

considers medical and obstetrical history of each patient and provides a list of absolute and relative contraindications in ‘check list’ format. It includes aerobic and muscular conditioning guidelines, safety considerations and reasons to stop exercise and seek medical advice. Most importantly, this tool is free and readily available online for use by medical and allied care providers.

This is an important first step in assessing patient readiness for participation in exercise during pregnancy.

A recent systematic review evaluated the

effects of aerobic exercise on maternal and neonatal outcomes. It included 14 research studies involving 1014 pregnant women and concluded that those who engage in 2-3 bouts of weekly exercise have similar pregnancy duration, risk of caesarean section and infant birth weight, as those who maintain their habitual activity level7. In other words, the results suggest that PA did not pose additional risks to mom or baby with respect to length of pregnancy, mode of delivery and weight of the baby. Importantly, aerobic exercise during pregnancy maintained or improved physical fitness of the mothers and

Table 1: Activity-induced changes in maternal physiology relative to the resting state PARAMETER

Heart rate (HR) Stroke volume (SV) Cardiac output (Q) Tidal volume (VT) Core temperature Placental perfusion Hemoconcentration Plasma volume Blood pressure Absolute energy expenditure for a given work load

CHANGE ↑ ↑ ↑ ↑ ↑ ↑ ↑ ↓ ↑

↑ (as a result of weight gain)

Source: Ferraro, Gaudet & Adamo 2012 Obs Gyn Surv 67(2): 99-110

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Research Associate, Division of MaternalFetal Medicine, The Ottawa Hospital.

PT Professor, Human Kinetics, Faculty of Health Science, University of Ottawa Dr. Ferraro received his PhD from the University of Ottawa where he studied maternal predictors and potential modifiers of fetal growth during pregnancy. He completed postdoctoral studies at the Children’s Hospital of Eastern Ontario and the Ottawa Hospital combining his interests in Maternal-Fetal Medicine and Pediatrics. His work continues to capture elements of clinical research, epidemiology and molecular medicine. He is a certified exercise physiologist (CSEP-CEP), has published over 20 peer-reviewed articles and was the inaugural recipient of the Canadian Obesity Network’s Rising Star award. More details available at www.DrFerraro.ca Follow @DrFerraro

it is well-established that cardiorespiratory fitness (i.e., VO2max) is a known contributor to reduced cardiovascular morbidity and allcause mortality8.

Exercise physiology and pregnancy Pregnancy and exercise are independently associated with significant changes in metabolism and physiology. However, care providers and fitness trainers alike must recognize that pregnant women are capable of benefitting from PA in a similar way that non-pregnant women do9 as the physiological response to physical exertion does not significantly differ compared to the nonpregnant state (Table 1). The physiological changes that occur during pregnancy PA are designed to protect the developing child by ensuring that the metabolic demands of both mother and baby are met. In fact, in the presence of adequate nutrition and caloric balance, the fetus is not deprived of substrate during bouts of maternal PA10,11.

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This effect may be mediated by changes in substrate delivery across the placenta arising from activity-induced alterations in placenta form and function12,13. Although an acute period of fetal hypoglyemia (i.e., low blood sugar levels in fetal circulation) may occur at the onset of maternal exercise, fetal glucose delivery has been shown to be enhanced due to a greater rate of substrate delivery and placental surface area available for uptake. The mechanisms responsible for the maintenance of placental blood flow, cord blood oxygen saturation and glucose delivery during exercise include maternal hemoconcentration (via decreased plasma volume), increased cardiac output and improved placenta perfusion14.

Consequently, the fetus appears to be protected from hypoglycaemia as a result of these placenta-mediated compensatory protective mechanisms.

A recent clinical study by May and colleagues15 compared low-risk pregnant women who exercised regularly throughout pregnancy (>30mins of aerobic exercise, 3x/wk) to healthy non-exercising controls and found, using fetal magnetocardiograms (a special device that monitors fetal heart rate(HR)), that fetal HR at 36 weeks gestational age was significantly lower and HR variability was significantly increased during maternal PA in the exercise group.

This finding countered previous research suggesting that a decrease in fetal HR seen during or immediately after maternal aerobic exercise was due to chronic fetal hypoxia16; one would expect decreased HR variability indicative of adverse stress on the fetal autonomic nervous system development if chronic hypoxia were present15. Interestingly, previous work examining the effect of regular exercise over the course of pregnancy compared to non-exercising controls found that maternal PA does not impair uteroplacental blood flow as measured by Doppler ultrasound scans of the uterine and umbilical artery pulsatility index immediately following a graded exercise test17.

Further, continuous exercise throughout gestation did not alter maternal serum erythropoietin (EPO) concentration18 and markers of fetal stress, such as EPO levels in cord blood and amniotic fluid have not been shown to increase during exercise in humans19 suggesting that fetal oxygenation

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is not impaired. As such, current evidence supports an active pregnancy for maternal and fetal wellbeing.

Energy expenditure during pregnancy During pregnancy, energy expenditure is altered, both at rest and with PA. Total energy expenditure, quantified by oxygen uptake (VO2), is the sum total of calories used at rest plus those expended when performing a given amount of external work. Pregnancy is generally associated with appreciable weight gain; this added mass contributes to the increase in energy expended at rest and during sub-maximal weight bearing activity (i.e., walking, running, stepping, etc.) relative to the non-pregnant state20. As a result, the metabolic cost of PA progressively increases from early to late pregnancy in proportion to the amount of gestational weight gain (GWG) and is independent of maternal PA status21.

Therefore, it is expected that the VO2 values relative to body weight (i.e., ml/kg/min) will remain similar or increase slightly when compared to the non-pregnant condition with similar exertion. Overall, pregnancy does not impair oxidative metabolism but rather impedes activity capacity due to the added weight of pregnancy. (As reviewed by Ferraro et al13).

Cardiorespiratory adaptations to physical activity during pregnancy Pregnancy-related maternal cardiovascular adaptations include an increase in blood volume, heart rate (HR), stroke volume (SV) and consequently cardiac output (HR x SV). Changes in chest wall anatomy (e.g., increased elasticity, flaring and expansion, elevated diaphragm) allow pregnant women to compensate during exercise with an increase in minute ventilation (tidal volume x breaths/ min) and tidal volume (volume inspired air/ breath). When the fetus presses upward into the chest cavity breathing may be more laboured, resulting in mild discomfort due to dyspnea.

Historically, there was concern that redistribution of blood flow to active muscles during physical exertion may impede delivery of nutrients and oxygen to the fetus leading to potential negative effects. However, in uncomplicated pregnancies, evidence suggests that moderateto-vigorous PA is considered acceptable and beneficial for both pregnant women and their developing offspring; provided there are no contraindications (Table 2)2.

Musculoskeletal adaptations of pregnancy and physical activity Physical discomfort is common during pregnancy and may be lessened/prevented with routine PA22. The anatomical changes of pregnancy include an anterior shift in the centre of gravity,

Table 2: Contraindications do Exercise in Pregnancy ABSOLUTE CONTRAINDICATIONS

RELATIVE CONTRAINDICATIONS

Ruptured membranes

Previous spontaneous abortion

Preterm labour

Previous preterm birth

Hypertensive disorders of pregnancy

Mild/moderate cardiovascular disorder

Incompetent cervix

Mild/moderate respiratory disorder

Growth restricted fetus

Anemia (Hb <100 g/L)

High order multiple gestation (triplets)

Malnutrition or eating disorder

Placenta previa after 28th week

Twin pregnancy ofter 28th week

Persistent 2nd or 3rd trimester bleeding

Other significant medical conditions

Uncontrolled type I diabetes, thyroid disease, or systermic disorder Note: reprinted and modified with permission from the Canadian Society for Exercise Physiology. 23 Davines, G.A.L all. (2003), Joint SOGCACSEP Clinical Pratice Guideline: Exercise in pregnancy and the postpartum period. Can. J. Appl. Physiol. 28(3): 328-341,

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exaggerated lordosis of the spine, protruding abdomen, rectus diastasis and altered gait.

Discomfort may be caused or worsened by ligament laxity from increased progesterone and relaxin that prepare the musculoskeletal system for delivery. Excessive GWG often leads to increased lower back, pelvis, and/or joint pain.

It is encouraging that musculoskeletal pain does not manifest in all pregnant women and may be attenuated with PA for those women who present with mild pelvic and lumbar discomfort22,23.

Having an awareness of the musculoskeletal and other anatomical changes characteristic of most pregnant women is useful to ensure advantageous outcomes when making activity recommendations and designing programs for this population.

Maternal physical activity and gestational diabetes mellitus Aerobic exercise during pregnancy improves insulin sensitivity in all pregnant women24. Those who report continuous activity before and during pregnancy have a lower risk of developing gestational diabetes mellitus (GDM), particularly when PA is performed at a moderate-tovigorous intensity25-27. These protective effects may be attributed to the regulation of glycemic control, which is essential to optimize pregnancy outcome11. In a randomized controlled trial, exercise and diet were compared to insulin therapy and diet with appropriate blood glucose levels as the primary outcome. There were no significant differences in maternal-fetal outcomes, suggesting that exercise and diet can be a safe and effective alternative GDM treatment during pregnancy28, 29. To gain the greatest protective benefit PA should be initiated early in life, strongly recommended to all women of childbearing age (particularly those who carry excess weight) and be maintained throughout the life course.

Maternal physical activity and preeclampsia Several studies have demonstrated that women who engage in moderate-to-vigorous intensity PA prior to and during uncomplicated pregnancies are at a reduced risk of hypertensive disorders30,31. Physical conditioning and preeclampsia have opposite effects on critical physiological functions such as placental growth and vascularity and susceptibility to oxidative stress and endothelial dysfunction31. Evidence suggests that PA has the greatest beneficial effects for pre-eclampsia prevention when www.sirc.ca

performed at a moderate-to-vigorous intensity prior to and during gestation11. Women who are active during pregnancy appear to have roughly a 40% risk reduction in developing preeclampsia25. Thus, appropriate PA appears to be a promising preventive strategy. However, a recent observational cohort study suggested that extreme amounts of aerobic exercise (>270 min/week) during the first trimester of pregnancy may increase the risk of developing pre-eclampsia. This provides evidence that women should not exceed the current PA recommendations32.

Maternal physical activity and preterm delivery PA during pregnancy has demonstrated to have no or a slight protective effect on gestational age at delivery and incidence of preterm birth (<37 weeks gestational age). For example, a recent systematic review of aerobic exercise interventions during pregnancy failed to show a significant adverse effect of maternal activity on preterm birth or mean gestational age 7 and a large population level cohort study that used selfreport measures of aerobic, resistance, low- and high-impact PA noted that their findings do not contradict current exercise recommendations as they found that PA during pregnancy had no effect on risk of preterm birth. Convincing evidence from a randomized controlled trial suggests that the effects of resistance training during pregnancy on previously sedentary, healthy women carrying singletons does not alter gestational age at delivery when compared to inactive controls33. Taken together, these results support the notion that healthy pregnant women, without contraindications to PA, are able to engage in active behaviours without undue risk of preterm birth.

Physical activity and fetal growth Exercise during pregnancy appears to be protective against birth weight extremes (i.e., small for gestational age (SGA) and large for gestational age (LGA)34. Simply, this means that regular PA increases the likelihood of delivering an appropriate for gestational age infant (a healthy normal size baby). Most studies have failed to show a detrimental effect on birth weight with moderate amounts of exercise35-43, suggesting that regular PA is safe and does not compromise fetal growth. Furthermore, a recently published randomized controlled trial concluded that exercise training may attenuate adverse consequences of maternal body

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weight on infant birth size44. The optimization of infant birth weight in women who engage in regular PA is thought to occur as a result of an increased functional capacity of the placenta to appropriately deliver nutrients via an increase in placental surface area, improvements in blood flow and an enhanced perfusion balance12,14.

Importantly, PA may prove most advantageous for overweight or obese pregnant women as a way to reduce their risk of delivering a LGA infant. Some studies have demonstrated a link between maternal PA and low birth weight45-48.

In these studies, an important limitation was lack of controlling for dietary intake. Many of these classical studies focussed on lean, healthy active women14, 49 and may not be generalizable to the other populations. Clapp noted an asymmetric reduction in birth weight of exercising mothers, a difference that was entirely accounted for by a reduction of neonatal fat mass with no changes in lean mass compared to the offspring of matched controls49. Overall, it appears that routine PA within the recommended guidelines is advantageous for both maternal weight management and neonatal size at birth.

Physical activity and lifestyle recommendations during pregnancy An ideal PA program for pregnancy must ensure that recommendations are appropriate for the individualsâ&#x20AC;&#x2122; fitness level, stage of pregnancy and degree of motivation while anticipating potential risks and identifying necessary pregnancy modifications. Promotion of individualized, activity-specific behaviours may discourage women from adopting excessive sedentary pursuits during pregnancy. After all, if the activity prescription is personalized, fun and enjoyable it is more likely to be sustained throughout the prenatal and postpartum period.

By now it should be no surprise that regular PA can help prevent or manage chronic conditions such as hypertension, obesity, GDM, dyspnoea and pre-eclampsia9, 31. For women contemplating pregnancy, it is important for the coach, care provider or allied professional to note that a lifestyle which includes preconception PA that continues through the prenatal and into the postpartum period is ideal. However, for previously inactive women, the SOGC-CSEP guidelines2 suggest that the best time to start an exercise program is in the second trimester when nausea, vomiting and fatigue of term one have passed and before the physical limitations of the third trimester begin. To ensure appropriate

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exercise intensity the SOGC-CSEP guidelines include recommended target HR training zones for the pregnant population that account for the 10-15 bpm pregnancy-associated rise in resting HR and thus the lower HR reserve during pregnancy. If coaches or providers do not have a HR monitor guidelines recommend the use of the ‘talk test’; a surrogate marker of PA intensity.

This ensures that the woman is exercising at a comfortable intensity if she is able to maintain a conversation during exercise; she should reduce the exercise intensity if ‘talking’ or ‘conversation’ at the given intensity is not possible2. Taken together the current guidelines provide a set of valuable tools and resources that coaches and providers may use to ensure appropriate prenatal PA advice.

While much of the research on active pregnancies has focussed on aerobic conditioning less evidence is available on strength, conditioning and resistance training in the prenatal period. According to the SOGCCSEP guidelines some women may experience symptomatic hypotension from compression of the vena cava by the pregnant uterus and should modify prenatal exercises to avoid the supine position after ~16 weeks. Further, performing abdominal exercises may be impeded by the development of diastasis recti and associated abdominal muscle weakness so these factors must be taken into account when designing a prenatal exercise program2.

Although preliminary, the limited research on resistance training during pregnancy comes from a high quality randomized controlled trial that suggests that light resistance training and toning exercises in mid-late pregnancy did not affect type of delivery, birth size or overall health of mom or baby33,44,50,51.

In any case, when it comes to PA behaviours some is better than none, but more is better than some. In the end, regular PA may help women meet GWG targets52,53 and thus have a positive influence on maternal-fetal outcomes. For athletes, appropriate GWG will facilitate less postpartum weight retention and encourage rapid return to competition. Table 3 provides a synopsis of recommendations for exercise in pregnancy. Of greatest importance prior to commencing PA during pregnancy is appropriate medical screening using the aforementioned PARmed-X for Pregnancy6.

Additionally, the Institute of Medicine (IOM) recently published updated GWG guidelines based on pre-pregnancy BMI (Table 4) that place an upper limit of recommended GWG

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Table 3: Sample exercise prescription for pregnant women without contraindications PROGRAM

PREVIOUSLY SEDENTARY

ACTIVE

Frequency1

3d/wk

4d/wk

Intensity

Low-moderate

Moderate-vigorous

2

Duration

15 min gradually to 30 min ≥ 30 min per session sessions

Type3

Low impact aerobics (swim, Low impact aerobics walk, cycle) Resistance/strength training

Resistance/strength training

Adapted from Can J Appl Physiol. 2003;28;330-341. 14 1

Brief warm-up and cool-down should be incorporated with each bout of activity.

2

The “talk test” may also confirm taht women are not over exerting.

3

Avoid exercise in the supine position after approximately 16 weeks’ gestation.

for all women54. Using regular PA coupled with healthy dietary intake will facilitate adherence to these guidelines. While it is understandable that elite athletes may look at this PA prescription and be concerned that the volume of recommended work is much lower than they are accustomed to, it is important to realize that pregnancy is a time to maintain fitness levels; not strive for personal best performances. Lastly, it is important to highlight safety precautions that all pregnant women must abide to independent of their relative or absolute contraindications for PA participation. Women should stop exercising

and seek medical attention if they experience excessive shortness of breath, chest pain, presyncope (light headedness), painful uterine contractions, amniotic fluid leakage and/or vaginal bleeding2. Abiding by these guidelines will ensure a healthy and safe pregnancy and facilitate rapid return to competition.

Exercise and pregnancy for elite athletes There is limited information in the academic literature concerning elite athletes and

Table 4: Guidelines for Weight Gain During Pregnancy: New IOM Recommendations adopted by Health Canada Pregnancy BMI

Total Weight

Rates of Weight Gain*

Gain

2nd and 3rd Trimester

Range in kg

Range in lbs Mcan (range) in kg/week

Mcan (range) in lbs/week

Undewrweight (<18.5 kg/m )

12.5-18

28-40

0.51 (044-0.58) 1 (1-1.3)

Normal weight (<18.5 kg/m )

11.5-16

25-35

0.42 (0.35-0.50) 1 (0.8-1)

Overweight (25.0-29.9) kg/m2) 7-11.5

15-25

0.28 (0.23-0.33) 0.6 (0.5-0.7)

Obese (≥ 30.0 kg/m2)

11-20

0.22(0.17-0.27) 0.5 (0.4-0.6)

2

2

5-9

* Calculations assume a 0.5-2 kg (1.1-4,4 lbs) weight gain in the first trimester (based on Siega-Riz et al., 1994; Abrams et al., 1995; Carmichael et al., 1997).

Source: Institute on Medicine, 2009 Based on WHO categories NOT Metropolitan Life Insurance tables

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pregnancy. However, a recent study published in the British Journal of Sports Medicine by Salvesen et al55 is timely with respect to the fetal response to extreme levels of maternal exertion in competitive Norwegian Olympic hopefuls. In their study examining fetal response and uteroplacental blood flow during strenuous treadmill running in the second trimester, Salvesen et al55 note that fetal HR was within the normal range as long as maternal exertion was below 90% maternal HRmax; an exercise intensity that would not be encouraged in a pregnant population. They reported that if maternal HR exceeded 90% of maximum value and uterine artery blood flow was simultaneously less than 50% the initial value, fetal bradycardia (lowered HR) occurred. However, despite these concerns, following exercise cessation fetal HR reached baseline values, uterine artery flow volume improved to resting values in most women and all birth weights were within the lower normal range for Norwegian children, which is encouraging.

Nonetheless, it is well accepted that adverse fetal effects of less vigorous maternal training are unlikely in uncomplicated pregnancies and that all pregnant women should follow the guidelines independent of preconception training status or fitness level.

Conclusion For women who are unaccustomed to PA and may be less inclined to engage, recent evidence suggests that yoga56 is a viable exercise modality and that a simple walking program of both low or vigorous intensity during pregnancy confers an aerobic benefit57. Given the strong association between aerobic fitness and all-cause mortality8 engaging in non-sedentary pursuits during gestation may be of tremendous value to limit disease and mortality risk later in life.

Furthermore, compared to those who were not active during pregnancy, active women showed attenuated decline in bone mineral density58 and improved psychological symptoms59 suggesting a protective effect of exercise that goes beyond one’s physiology.

Overall, a physically active pregnancy is a safe and effective means of improving fitness and managing GWG in most women (i.e., those without contraindications). So while health care providers should continue to exercise caution with respect to PA prescription and first do no harm, it is important to understand that a physically active lifestyle does not necessarily imply the absence of sedentary behaviours

which have their own independent ill-effects on health. Thus every little movement counts and discouraging excessive sedentary pursuits may provide additional health benefits and be a target for behaviour intervention above solely meeting PA recommendations60. It is important for all pregnant women, recreational and elite athletes alike, to have an open and honest relationship with their obstetrician or medical care provider.

Those engaging in levels of PA near the upper limit should be monitored and supervised more closely by a physician who is knowledgeable of the impact of strenuous exercise on maternalfetal outcomes to ensure optimal fetal growth and development. Therefore, being able to confidently make lifestyle recommendations and troubleshoot barriers to participation in all women that go beyond the simple and ineffective ‘eat less and move more’ approach may have long lasting benefits to maternal-fetal and potentially downstream child health. ∆ For references, click here

Watch this online webinar where the author Zach Ferraro presents his research on the topic of exercise, pregnancy and elite athletes.

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facts Did You Know?

Women who have been previously active may continue their exercise during the first trimester to a maximum of 30-40 minutes at a frequency of 3-4 x a week as tolerated.

Heart rate is less reliable in pregnancy for determining exercise intensity. The modified heart rate target zones, as outlined in the PARmed-X, are recommended for use in measuring exercise intensity in pregnant women.

Candian Academy of Sport and Exercise Medicine (CASEM) Position Statement – Exercise and Pregnancy

Reasonable goals of aerobic conditioning in pregnancy should be to maintain a good fitness level throughout pregnancy without trying to reach peak fitness or train for an athletic competition. Elite athletes who continue to train during pregnancy require supervision by an obstetric care provider with knowledge of the impact of strenuous exercise on maternal and fetal outcomes.

Joint Society of Obstetricians and Gynaecologists of Canada/ Canadian Society for Exercise Physiology Clinical Practice Guideline: Exercise in Pregnancy and the Postpartum Period.

on pregnancy

Elite athletes and pregnancy: Biomechanical changes and adaptations There’s no arguing that pregnancy changes a woman’s body, but if you’re an athlete, it means so much more than that. A recent study has shown that the changes in a woman’s body during pregnancy can affect the way they move after giving birth.

Many physiological changes occur in a woman’s body during pregnancy with one of the most significant changes being that of weight gain. This weight gain is obviously necessary in order for the baby to develop properly, however this increase in body mass shifts the body’s centre of gravity, weakens the abdominal muscles and slightly shifts the pelvis.

These changes contribute to an increased base of support, a larger foot progression angle, increased pelvic movements and an increased rotation of the pelvis. This is loosely described as a “waddling gait”.

Many female elite athletes are choosing to continue training throughout their pregnancies, with good results. Each athlete needs to take into consideration their own unique needs and tailor their training to suit.

Some popular exercises for elite athletes who are training while pregnant include:

• bungee cords for resistance • zero gravity treadmills

• brisk walking • stationary cycling

• swimming During the third trimester of pregnancy, babies grow rapidly which increases the pressure on the abdominal muscles. That pressure can cause the rectus abdominis, a paired muscle running vertically down the front of the abdomen, to separate. This separation is called diastasis recti, and it can occur to various degrees above or below the belly button. Because this separation occurs, it is recommended that women avoid traditional sit ups until the body is fully healed. Additionally, ligaments and joints tend to be loose for up to three months post partum, so it’s important to adjust training to minimize the risk of injury.

Some suggestions for exercises to restore the strength and stability in the abdominal muscles after pregnancy include planks, squats and bridges.

Sources: Gilleard WL. Trunk motion and gait characteristics of pregnant women when walking: report of a longitudinal study with a control group. BMC Pregnancy Childbirth.

March 2013;13:71.

Kardel K. Effects of intense training during and after pregnancy in top-level athletes. Scandinavian Journal Of Medicine & Science In Sports. April 2005;15(2):79-86.

Reynolds, Gretchen. How Pregnancy Changes a Women's Body. The New York Times. July 2013. Web.

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PREGNANCY IN SPORT POLICY AND GUIDELINES

AlterG® Anti-Gravity Treadmill The AlterG® anti-gravity treadmill uses air in a pressure-controlled chamber to gently lift an athlete, decreasing impact during walking and running. While mainly used to rehabilitate athletes recovering from an injury, long-distance runners Kara Goucher and Paula Radcliffe both used this treadmill for training during their pregnancies in 2010. The main benefit of using an anti-gravity treadmill is that it allows the athlete to manipulate the body weight by creating a vertical lift that reduces the impact on the body.

• Unlike other low impact cardio equipment, the AlterG® enables athletes to train with their natural gait and rhythm • Allows you to walk or run between 20 and 100 percent of your body weight • Lowers the impact on joints and muscles during exercise • Helps minimize discomfort and encourages movement • Creates a safe environment to work on technique Running on an AlterG® treadmill is similar to pool running in that it reduces the athlete’s body weight to allow them to move more freely without compressing the joints in the hips, knees and back.

The main difference between pool running and anti-gravity treadmills is that the treadmills do not have the resistance that pool running creates. Anti-gravity treadmills are as easy to use as regular treadmills in that the user can control speed, incline and how much of their body weight they would like to reduce. Other elite athletes who use this type of treadmill include 2012 Olympic gold and silver medalists Mo Farah and Galen Rupp.

Source: McDonald Neitz, Katie. Great Expectations. Runner’s World. August 2010

• Exercise and Pregnancy Position Statement. Canadian Academy of Sport & Exercise Medicine (CASEM).

• Exercise and Pregnancy Discussion Paper. Canadian Academy of Sport & Exercise Medicine (CASEM).

• Sport & Maternité. France: Ministères de la Santé et des Sports. Secrétariat d’État aux Sports. (French only) • Exercise in Pregnancy and the Postpartum Period. Joint Society of Obstetricians and Gynaecologists of Canada / Canadian Society for Exercise Physiology (SOGC / CSEP) Clinical Practice Guidelines • Pregnancy in Sport: Guidelines for the Australian Sporting Industry. Australian Sports Commission.

• SMA Statement:The benefits and risks of exercise during pregnancy. Sports Medicine Australia.

• Sports Medicine Australia Guidelines: Participation of the pregnant athlete in contact and collision sports. Sports Medicine Australia.

Ask SIRC I have been an athlete all my life and while I am taking some time away from sport to have a family, I still plan on continuing with some modified training. I understand that I will probably have to adjust my diet to accommodate my pregnancy, do you have any information on pregnancy and nutrition for athletes?

Pregnancy is an exciting time for anyone and paying attention to the safety of mother and child is always of the utmost importance. Many women these days, whether competitive or recreational athletes, continue with training, under a doctor’s supervision, for as long as it remains safe to do so.

Nutrition is also a very important factor in an athlete’s training plan, so recognizing that a pregnant athlete will have specialized nutritional needs is even more important.

• Risk of Abdominal Injury to Women During Sport. Sports Medicine Australia • The pregnant athlete, part 2: Exercise recommendations. National Collegiate Athletic Association • The pregnant athlete, part 3: Exercise in the postpartum period and return to play.

National Collegiate Athletic Association

Here are some documents and organizations that may help you understand the nutritional concerns of a pregnant athlete: Modified Heart Rate Target Zones for Aerobic Exercise in Pregnancy

• Fueling the pregnant athlete • The Pregnant Triathlete • What to Eat During Pregnancy

Maternal Age

Heart Rate Target Zone (beats/min)

Heart Rate Target Zone (beats/10 sec)

Less than 20

140-155

23-26

20-29

135-150

22-25

130-145

21-24

125-140

20-23

Organizations: 30-39 • Dieticians of Canada 40 or greater • Sports Dieticians Australia • Academy of Nutrition and Dietetics. Sports, Cardiovascular, and Wellness Nutrition (SCAN)

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Source: Canadian Society for Exercise Physiology.

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MUST READ...

Must Reads …

Read, Excel, Learn

IST Journal Club The goal of the IST Journal Club is to share ‘must reads’ on cutting edge performance based applications, training/competition variables, and proactive medical interventions, selected by performance service experts representing various professional disciplines associated with Integrated Support Teams.

Iron Supplementation for Female Athletes: Effects on Iron Status and Performance Outcomes.

DellaValle, D.M. Current Sports Medicine Reports (2013); 12(4), 234-239.

Reviewed by Heather Hynes This review article highlights the current research regarding iron status within the athletic population and the impact that iron deficiency may have on aerobic performance. The author identifies the need for specific cut off blood values for both male and female athletes; noting that the clinical blood markers for iron deficiency may be too low. An athlete’s performance may already be compromised even if their lab values, specifically hemoglobin and serum ferritin, are within the normal range. The current recommended daily allowances (RDA) for iron are also discussed; they are currently set at 18mg/day for healthy premenopausal females.

Additional research is needed with the athletic population to identify if this RDA is appropriate due to the additional stress placed on the body with physical training. Ideal iron supplementation protocols are discussed and the available research conducted with an athletic population is presented. The author concludes by stating the importance of ongoing monitoring of an athlete’s blood values. Athletes and coaches need to be aware of the health concerns with iron overload and that all iron supplementation protocols should be assessed by a health professional. ∆ 28

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New Books @ SIRC SIRC, in collaboration with Human Kinetics, features four books of interest to high performance sport.

Biomechanics of Sport and Exercise McGinnis, P. (2013) Human Kinetics.

Facilitated Stretching

Nancy Clark’s Sports Nutrition Guidebook

McAtee, R.E., Charland, J. (2013). Human Kinetics.

Clark, N. (2013). Human Kinetics.

Skeletal muscle oxidative function in vivo and ex vivo in athletes with marked hypertrophy from resistance training.

Salvadego D, Domenis R, Grassi B, et al. Journal Of Applied Physiology. June 2013;114(6):15271535.

Reviewed by Matt Jordan The possibility that chronic strength training and the concomitant increase in muscle strength, muscle power and hypertrophy may enhance oxidative muscle function has been of great interest for improving athletic performance.

However, mixed evidence and opinion exists amongst experts. In order to address this issue, the authors investigated oxidative muscle function in functional performance tests and through muscle biopsy in resistance trained subjects compared to control subjects. The main finding was that resistance trained subjects displayed enhanced mitochondrial respiratory function compensated for the decreased ability for oxygen extraction by the muscle associated with marked hypertrophy. The overall result was better whole-body oxidative function at peak exercise but no significant differences in efficiency at submaximal exercise intensities. ∆ Français

Running Science Anderson, O. (2013).

Human Kinetics.

Jump Performance Analysis of World-Class Mogul Skiers Over an Olympic Quadrennial Cycle Case Study.

Pethick, W. A., Murray, H. J., Gathercole, R. J., & Sleivert, G. G. (2014). International Journal Of Sports Physiology & Performance, 9(1), 128132.

Reviewed by Leo Thornley Our very own Pethick and colleagues offer a great case study, showing how consistently collecting data over the course of the quadrennial can help elucidate the changes that occur in the key performance factors. Knowing that jump performance is highly correlated to performance in Mogul skiing, this case study tracked jump performance over the four years leading into the 2010 Vancouver Olympics.

This paper highlights the importance of longitudinal data collection as well as understanding the variability and smallest worthwhile change of performance measures. ∆

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Top 10 Guiding Principles for Mental Training.

McCann S. Soccer Journal. July 2008;53(4):36-38.

Reviewed by Judy Goss If you are anything like me, you might find yourself harmlessly “googling” something and soon find yourself 10 clicks away from where you started and wondering how you got there. I have been doing some research on competitive hardiness which often takes you to mental toughness and happened upon a great list! The Top 10 Guiding Principles of Mental Training by Sean McCann. Sean is a sport psychologist for the USOC and has travelled to many Olympic Games. After I read the list, I couldn’t help but admire the simple and concise way he presented the information. I also felt that in preparation for high level competition there are some guiding principles that need to be reinforced. #2 Physical training and physical ability isn’t enough to succeed consistently.

Basically if you can’t handle the mental demands of training and competition you will not perform well consistently. At the Olympics, the physical demands of the game, event or race are the same, but everything else is different. That is a lot of manage. #7 Coaches must be involved in the mental training process. The physical and mental training go hand in hand and they need to be integrated. And my new favourite #8 Sometimes it is ok to force athletes to take the time to do mental training. We often want for athletes to come to us, be willing and want to learn. What generally happens is a crisis and then they come and see you. Don’t wait for a crisis, be prepared, train the mental skills. ∆ Rationale and resources for teaching the mathematical modeling of athletic training and performance.

Clarke, D.C. and Skiba, P.F. (2013) Advan in Physiol Edu. 37: 134-152.

Reviewed by Allan Wrigley This is one of the more interesting papers I have read in quite some time. The authors present a rationale for using mathematical models for the design, prescription, and evaluation of athletic training and performance. What is particularly

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interesting is that the target audience is exercise physiologists, and more specifically those that would teach other practitioners. Although mathematical modeling in sport performance is not uncommon, it is not widespread through the area of exercise physiology and associated disciplines simply due to a lack of developed curriculum and education. The authors provide a very interesting definition of evidence-based practices, and how performance modeling helps to address exactly that. Two different models are presented, along with references for lecture material, teaching strategies, and even a supplemental annotated spreadsheet for computer-based assignments. All of the mathematics provided can be tailored to the audience, as the level of sophistication is modifiable so that it can be more broadly accessible. Overall, a good case is made for general program design based on the published concepts and guidelines from peer reviewed research that is then optimized based on systematically collected training and performance data modeled using the outlined performance models. ∆ Variability and Predictability of Performance Times of Elite Cross-Country Skiers.

Spencer, M., Losnegard, T., Hallén, J., & Hopkins, W. G. (2014).

International Journal Of Sports Physiology & Performance, 9(1), 5-11.

Reviewed by Leo Thornley Spencer and colleagues show that even in a sport such as cross country skiing, where events occur at different venues on different terrain and under different conditions, performance can be predicted and understood. The key to understanding performance is collecting good performance data. Once analyzed appropriately, inferences can be made about performance changes and whether they are on track, whether training interventions actually made a performance difference or not and even about how a junior athlete is progressing. (Spencer & Losnegard, 2013). ∆

Improvements in Hip Flexibility Do Not Transfer to Mobility in Functional Movement Patterns.

Moreside J, Mcgill S. Journal Of Strength & Conditioning Research (Lippincott Williams & Wilkins).

October 2013;27(10):2635-2643.

Reviewed by Bruce Craven STRETCH! In preparation for Sochi, many athletes were instructed by their coaches, strength and conditioning trainers and therapists to stretch. In this article by Moreside and McGill, the evidence for more stretching to improve range of motion at the hip was questioned as it relates to functional movement. The researchers analyzed the transference of increases in passive hip range of motion and core endurance to functional movements such as active standing hip extension, lunging, a standing twist/ reach maneuver and exercising on the elliptical trainer. The study involved 24 males with limited hip range of motion randomly assigned to 4 groups (group 1 a stretching only program; group 2 stretching plus hip/spine disassociation exercises; group 3 core endurance training and group 4 a control group). Following a 6 week training program there was a large increase in passive hip range of motion in both groups 1 and 2. Despite these large increases in hip passive range of motion from stretching, there was no change in the functional hip extension range during the functional exercises.

Remember that there is a need to incorporate motor learning and strengthening of new ranges as a result of stretching into exercise technique and performance, as this article and others indicates that stretching alone does not transfer into range of motion during performance. ∆

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Performance Enhancement Effects of Federation Internationale de Football Association’s “The 11+” Injury Prevention Training Program in Youth Futsal Players.

Reis I, Rebelo A, Krustrup P, Brito J. Clin J Sport Med 2013; 23 (4): 318-320.

Reviewed by Brian Benson Canadian National coaches, high performance directors, and integrated support teams (ISTs) are currently focussed on optimizing individual athlete training and competition performances.

Ensuring athletes are healthy and fit are fundamental principles of performance enhancement, and injury prevention plays an important role in this. Recent evidence suggests that the use of a standardized progressive warmup program may augment physical fitness and technical performance gains while at the same time reduce athletes’ risk of injury. Reis et al.

(2013) conducted a randomized controlled trial utilizing 36 male futsal players (mean age: 17.3 years) to determine if there were significant performance effects associated with Federation Internationale de Football Association’s (FIFA’s) “The 11+” injury prevention warm-up program.

The intervention group performed The 11+ program two times per week for 12 weeks, which included: 1.

slow-speed running exercises, stretching, and controlled contacts with a partner;

2.

six sets of strength, balance, and jumping drills, each with three levels of increasing difficulty; and

3.

speed running combined with changes in direction.

The control group warmed up with standard jogging and ball exercises.

Results demonstrated significant improvements in strength, sprinting, agility, jumping, balance and skill outcome measures in the intervention group (P<0.05). An earlier cluster-randomized controlled trial by Soligard et al. (2008) demonstrated the effectiveness of The 11+ warm-up program in reducing female soccer players’ overall injury risk by one-third and risk of severe injuries by one-half. This study illustrates how athletes, coaches and multidisciplinary members of the IST can directly align themselves and work together towards a common goal (performance enhancement) with various training interventions, with a “side benefit” of injury prevention. ∆

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Ask SIRC

Is your VO2max a number worth knowing?

VO2max is the maximum volume of oxygen consumed per minute primarily by the skeletal muscles of an athlete. The term broken down actually stands for V (volume per time), O2 (oxygen), Max (maximum). It takes a maximum aerobic effort to reach VO2 max. A high VO2max has been highly touted by athletes and coaches since the more oxygen you can process the faster you will be able to go. World class endurance athletes, such as crosscountry skiers, cyclists and runners, typically have the highest readings.

The most common way to measure VO2max is to perform the test on an exercise bike or treadmill. It is a progressive exercise test that starts at an easy pace that gradually accelerates and finishes at “voluntary exhaustion” after 10 to 12 minutes. During exercise, oxygen consumption is measured continuously till it reaches its maximal value (VO2max). This test should be performed by an Exercise Physiologist and requires sophisticated lab equipment. There are many universities and labs across Canada that can perform a VO2max test for an athlete - they generally cost around $100-150.

For many elite athletes, the number is used as a tool to optimize their training, by using the number as a benchmark to monitor progress and increase their performance. According to researchers, having a high VO2max will certainly give you an edge but will not guarantee an elite-level performance as a high number is largely genetically determined. What an athlete is actually capable of doing with the added energy depends on many other factors (for example, the mechanical efficiency with which you move at a given speed or the relative proportion of fast and slow twitch muscles). Essentially, knowing your VO2max can be indicator of potential but is only one facet of an elite athletes’ measure for success.

The highest VO2max ever recorded was a score of 97.5 by Norwegian cyclist Oskar Svendsen in 2012.

References from the SIRC Collection: 1. Five Lessons I Have Learned from Physiology and How They Can Make You a Faster Runner.

Karp J., Olympic Coach. Spring 2012 2012;23(2):4-10.

2. Prediction of Maximal Oxygen Uptake from Submaximal and Maximal Exercise on a Ski Ergometer. Klusiewicz A, Faff J, Starczewska-Czapowska J., Biology Of Sport. March 2011;28(1):31-35.

3. Let a Fitness Assessment Start off Your Year. Running & Fitnews. November 2010;28(6):7-10.

4. The Clinic. Your VO2 Max is a Number Worth Knowing. Munsey K, LaFontaine T., Running & Fitnews. September 2010;28(5):22-23.

5. Determining Anaerobic Capacity in Sporting Activities. Noordhof D, Skiba P, de Koning J., International Journal Of Sports Physiology & Performance. September 2013;8(5):475-482.

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Recommended Readings In our collaborative effort to bring you the latest research in high performance sport, Own The Podiums has selected specific areas of interest to coaches and trainers and SIRC has culled through our resources to provide access to recent research published within these areas.

Periodization Applied Periodization: A Methodological Approach. Naclerio F, Moody J, Chapman M. Journal Of Human Sport & Exercise. July 2013;8(2):S350-S366.

Solutions to the Programming Puzzle.

Buchheit M, Laursen P. High-Intensity Interval Training, Sports Medicine. May 2013;43(5):313-338.

Solutions to the Programming Puzzle.

Buchheit M, Laursen P. High-Intensity Interval Training, Sports Medicine. October 2013;43(10):927-954.

Competitive Performance, Training Load and Physiological Responses During Tapering in Young Swimmers.

Toubekis A, Drosou E, Gourgoulis V, Thomaidis S, Douda H, Tokmakidis S. Journal Of Human Kinetics. September 2013;38:125-134.

Nutrition Performance Level Affects the Dietary Supplement Intake of Both Individual and Team Sports Athletes. Giannopoulou I, Noutsos K, Apostolidis N, Bayios I, Nassis G. Journal Of Sports Science & Medicine.

March 2013;12(1):190-196.

Influence of Growth Rate on Nitrogen Balance in Adolescent Sprint Athletes.

Aerenhouts D, Van Cauwenberg J, Poortmans J, Hauspie R, Clarys P. International Journal Of Sport Nutrition & Exercise Metabolism. August 2013;23(4):409-417.

Polymorphic variants of the PPAR (Peroxisome Proliferator-Activated Receptor) genes: relevance for athletic performance. Maciejewska-Karłowska

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A. Trends In Sport Sciences. August 2013;20(1):5-15.

The differential effects of a complex protein drink versus isocaloric carbohydrate drink on performance indices following high-intensity resistance training: a two arm crossover design. Lynch S. Journal Of The International Society Of Sports Nutrition.

July 2013;10(1):1-10.

Psychology “In the Boat” but “Selling Myself Short”: Stories, Narratives, and Identity Development in Elite Sport. Carless D, Douglas K. Sport Psychologist. March 2013;27(1):27-39.

How Should We Measure Psychological Resilience in Sport Performers? Sarkar M, Fletcher D. Measurement In Physical Education & Exercise Science. October 2013;17(4):264-280.

A Qualitative Evaluation of the Effectiveness of a Mental Skills Training Program for Youth Athletes. Sharp L, Woodcock C, Holland M, Cumming J, Duda J. Sport Psychologist. September 2013;27(3):219-232.

Unexplained Sporting Slumps and Causal Attributions. Ball C. Journal Of Sport Behavior. September 2013;36(3):233242

Anti-Doping Psychological Mechanisms Underlying Doping Attitudes in Sport: Motivation and Moral Disengagement. Hodge K, Hargreaves E, Gerrard D, Lonsdale C. Journal Of Sport & Exercise Psychology.

August 2013;35(4):419-432.

Coaching An Integrated Research Model of Olympic Podium Performance. Din C, Paskevich D. International Journal Of Sports Science & Coaching. June 2013;8(2):431444.

Getting Them on the Same Page: A Method to Study the Consistency of Coaches’ and Athletes’ Situation Understanding During Training Sessions and Competitions. Macquet A. Sport Psychologist. September 2013;27(3): Data Mining in Elite Sports: A Review and a Framework. Ofoghi B, Zeleznikow J, MacMahon C, Raab M. Measurement In Physical Education & Exercise Science. July 2013;17(3):171-186.

Long-Term Athlete Development Creating a Champion: Identifying Components that Assist Skill Development in Young Speed Skaters.

Hillis T, Holman S. International Journal Of Sports Science & Coaching. March 2013;8(1):33-42.

Importance of the Coordinative Abilities Development in Optimizing the Selection Process for the Elite Athletes. Juravle I. Sport & Society / Sport Si Societate.

February 2013;13:28-31.

Psychology Applying Implementation Science to Sports Injury Prevention. Donaldson A, Finch C. British Journal Of Sports Medicine.

May 15, 2013;47(8):473-475.

Anterior Cruciate Ligament Injuries: Recognising Potentially High-Risk Athletes. Munro A. Sportex Medicine.

January 2013;(55):7-10.

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Calendar For more events, check out the SIRC Conference Calendar.

March February 27 – March 2 March 14-16 March 18-21

2014 CAHPERD State Conference, Garden Grove, California 7th Summit on Communication and Sport, Cornell Club, New York Gathering Our Voice Aboriginal Youth Conference, Vancouver, British Columbia

April April 10-12

6th Exercise & Sports Science Australia Conference and Sports Dietitians Australia

April 10-12

IOC World Conference on Prevention of Injury & Illness in Sport, Monte-Carlo, Monaco XII International Symposium Biomechanics and Medicine in Swimming, Canberra,

April 28–May 2

Adelaide, South Australia

Australia

May May 14-17 May 23-24 May 28-31

16th European Society of Sports Traumatology Knee Surgery and Arthroscopy Congress, Amsterdam, Netherlands Perspectives in physical education and sport, Constanta, Romania American College of Sports Medicine (ACMS) Annual Meeting, Indianapolis, United States

June June 12-15

World Congress on Science and Soccer 4.0, Portland, Oregon The 2014 Wingate Congress of Exercise and Sport Sciences, Netanya, Israel

June 18-21

The XXXIII FIMS World Congress of Sports Medicine, Quebec City, Canada

June 4-5

For more information

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Pour plus d’information

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sirc.ca/SIRCuitHP

www.sirc.ca