HP SIRCuit winter 2016

SIRCuit HIGH PERFORMANCE

“Merging COACHING with SPORT SCIENCE & MEDICINE” Winter 2016

The Gord Sleivert Young Investigator Awards Also inside: Canadian Sport Institute Pacific – Three Major Campuses Offering World Class Programming A decision-matrix for determining risk in talent selection Peak Height Velocity and the Developing Athlete: What’s new in the research?

Must Reads … Read, Learn, Excel

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Editorial Welcome to the winter issue of the High Performance SIRCuit. The successes seen in sport over the last year clearly demonstrated why the Government of Canada recognized the importance of sport by declaring it the Year of Sport in Canada. As we move into 2016 the drive for excellence continues as athletes, their coaches and our teams are getting ready for world championships, Olympic qualifiers and the upcoming Games in Rio. We’re seeing great advancements in sport science research and valuable sharing of insights between coaches that no doubt may give our athletes the competitive edge to reach the podium.

This issue of the HP SIRCuit will focus on the award winners of the 3rd annual Gord Sleivert Young Investigator Awards which celebrates and encourages innovation in research among up and coming young sport scientists. The three top research projects awarded addressed the following subject areas:

• Equipment Advances to Improve the Lab-based Measurement of a BMX Sprint Start.

• Development of a reliable evaluation protocol to use for longitudinal shoulder injury follow-up of swimmers Also look for the focus on the Canadian Sport Institute Pacific as they highlight their training and performance support facilities and services, and the thought-provoking article looking into a decision-matrix for determining risk in talent selection.

Debra Gassewitz President & CEO SIRC

Special thanks to the NSSMAC editorial and SIRC/OTP teams for reviewing and recommending some excellent research for coaches and ISTs to read, highlighting some of the latest work being done in the area of high performance.

Yours in sport, Jon and Debra

• An evaluation of the effects of fatigue on the preparatory quadriceps/hamstrings activity prior to jump landing in actively competing elite alpine ski racers with/without ACL reconstruction

Jon Kolb, PhD

Director, Sport Science, Medicine and Innovation Own the Podium

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Editor

Contributing Editor Dr. Jon Kolb, OTP

Special Thanks

Debra Gassewitz, SIRC

Content

Contributors

Translation

Nancy Rebel, SIRC

Circulation Kim Sparling, SIRC Design

Josyane Morin

Joseph Baker Jeremiah Barnert Mathieu Charbonneau Les Gilson Sylvain Guadet Matt Jensen Matthew Jordan Eugene Liang Scott Maw Paddy McLuskey Erik Sesbreno Leslie Toogood Nick Wattie

Canadian Sport Institute Pacific Marcel Nadeau

Photos Courtesy of:

Alpine Canada Alpin CSI Pacific Cycling Canada Cyclisme SIRC

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

Mailing address: SIRC PO Box 53169, Rideau Centre RO Ottawa, Ontario, Canada, K1N 1C5 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 © 2016 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

A decision-matrix for determining risk in talent selection

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Canadian Sport Institute Pacific – Three Major Campuses Offering World Class Programming

Peak Height Velocity and the Developing Athlete: What’s new in the research?

Dr. Gord Sleivert Young Investigator Awards

The Young Investigator Awards are a tribute to the sport science leadership and innovation that Dr. Sleivert shared with High Performance in Canada.

• 1st Place: Preparatory Quadriceps/Hamstrings Activity in Elite Skiers: Time to Train for Fatigue? (Matt Jordan) • 2nd Place: Equipment Advances to Improve the Lab-based Measurement of a BMX Sprint Start. (Matt Jensen) • 3rd Place: Validation of an evaluation protocol combining isokinetic strength testing, electromyography of the shoulder and of a novel statistical analysis method. (Sylvain Gaudet)

Canadian Sport Institute Pacific – Three Major Campuses Offering World Class Programming

Over the past five years, CSI Pacific has been more focused than ever on identifying and developing up and coming Canadian athletes and coaches. With the support of OTP, the Province of British Columbia, and our NSO and PSO partners, we have created some groundbreaking programming in Canada

A decision-matrix for determining risk in talent selection

Athlete development is a heavily nuanced, extended process that typically involves a series of stages (or selections). These selections ultimately determine who is able to move on to the upper levels of competition and coaching.

Peak Height Velocity and the Developing Athlete: What’s new in the research?

A variety of studies published since 2014 have taken a look at a number of different areas of athlete development and its relation to PHV.

Must Reads … Read, Learn, Excel

• IST Journal Club Reviews • Recommended Research Readings from SIRC & OTP • New Books @ SIRC

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The Gord Sleivert Young Investigators Awards Dr. Gord Sleivert was a pioneer in the field of sport physiology and established innovative training systems and instruments. Established in 2013, The Dr. Gord Sleivert Young Investigator Awards are 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.

Quadriceps/ 1st Preparatory Hamstrings Activity in

Elite Skiers: Time to Train for Fatigue?

Authors: Matthew J. Jordan, Per Aagaard, Walter Herzog

Advances to Improve 2nd Equipment the lab-based Measurement of a BMX Sprint Start

Authors: Jensen MJ, Sporer B, Wooles AL, Klimstra MD

3rd

Validation of an evaluation protocol combining isokinetic strength testing, electromyography of the shoulder and of a novel statistical analysis method

Authors: Sylvain Gaudet, M.Sc, Jonathan Tremblay, PhD, Mickael Begon, PhD 4

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Preparatory Quadriceps/ Hamstrings Activity in Elite Skiers: Time to Train for Fatigue?

Authors: Matthew J. Jordan1, Per Aagaard2, Walter Herzog1 Affiliation: 1 Human Performance Laboratory, The University of Calgary 2 Department of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC), University of Southern Denmark

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nterior cruciate ligament (ACL) injury occurs frequently in elite alpine ski racing and injuries happen often at the end of the race, presumably when risk factors stemming from acute muscle fatigue are involved1, 2. Elite alpine ski racers demonstrate a high rate of ACL re-injury10, and despite a full return to sport, ACL reconstructed (ACLR) ski racers continue to display neuromuscular deficits including elevated bilateral functional asymmetry and quadriceps/hamstrings strength deficits in the involved limb8, 9.

In addition to minimizing functional asymmetry and developing sufficient quadriceps/hamstrings strength, the ability to engage the thigh muscles to dissipate external energy and create dynamic knee joint stabilization is important for ACL injury prevention5. Of interest is the preparatory quadriceps/hamstrings muscle activity levels that stiffen the knee joint prior to dynamic decelerating events such as landing from a jump or side cutting11. However, neuromuscular fatigue can diminish ACL protective mechanisms12 and may lead to increased ACL loading3.

Given the high risk for ACL injury in elite ski racers and the frequent occurrence of injuries at the end of a race when fatigue is present, we used an 80-second repeated squat jump test (jump-test) to elicit acute neuromuscular fatigue and evaluated the effects of fatigue on the preparatory quadriceps/hamstrings activity prior to jump landing in actively competing elite alpine ski racers with/without ACLR.

Methods Twenty-two elite skiers competing at the International level were recruited from Canada’s national alpine skiing and skier cross programs including 11 controls with no history of ACL injury and 11 actively competing ACLR skiers. Subjects performed a jump-test that involved one maximal vertical jump every four seconds for 80-seconds from a static squat position held at 90 degrees of knee flexion. The jump-test was performed on a set of dual force plates that was synchronized with the

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surface electromyography (EMG) signal6,8.

Surface EMG signals were recorded (Sampling Frequency = 1500 Hz) from the quadriceps (vastus lateralis, vastus medialis) and hamstrings (biceps femoris, semitendinosus) muscles, and normalized to a maximum voluntary contraction. The normalized EMG root mean square (50-ms time constant) amplitudes averaged over 25 ms just prior to touchdown following the vertical jump were obtained. Quadriceps vs hamstring dominance were determined

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as the difference between quadriceps and hamstring EMG activity (quadricepshamstrings)11. Fatigue was evaluated by averaging all outcome measures over sets of five jumps within the 20 jump test. The values in the final five jumps (fatigue, Set 4) were then compared to the first five jumps (rested, Set 1). A multi-level statistical model was used to compare the effects of the group and limb status on the outcome measures (two-tailed, α=0.05).

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Results Vertical jump performance declined significantly for both groups from Set 1 to Set 4 [χ2 (127.5), df = 3, P<0.0001]. Preparatory differential quadriceps-hamstrings activity levels differed between limb conditions [χ2(12.1), df = 2, P<0.01]. No differences emerged for the uninvolved limb of the ACLR skiers compared to controls [P=0.93].

However, the involved limb demonstrated reduced differential quadriceps-hamstrings activity (i.e. more hamstring dominance) compared to the uninvolved limb and the controls (Figure 1, bottom right panel).

Additionally, differential activity levels increased with fatigue for all limb conditions [χ2(73.8), df = 3, P<0.0001]. The mean

Matt Jordan is a strength coach, the Director of Strength and Conditioning for the Canadian Sport Institute-Calgary and the Director of Sport Science and Sport Medicine for Alpine Canada. He also provides private strength coaching and sport science consultation to elite athletes through his business. A special interest of Matt’s is injury prevention. He is currently completing his Doctorate in Medical Science at the University of Calgary focusing on ACL Injury/Re-Injury Prevention in Elite Alpine Ski Racers.

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(± SE) differential quadriceps-hamstrings activity increased across all limb conditions from Set 1 to Set 4 indicating a shift towards quadriceps dominance [P<0.001] (Figure 1, bottom left panel). When comparing differential vastus lateralis-semitendinosus activity (normalized VL-ST EMG) only a tendency for a difference between limbs was observed [P=0.06]. Similar to gross differential quadriceps-hamstrings muscle activity, differential medial (VL-ST) muscle activity increased with fatigue for all three limb conditions indicating a progressive quadriceps dominance [P<0.001] (Figure 1, top right panel).

Practical Considerations and Key Conclusions In our previous work, we showed that despite a full return to sport, ACLR skiers may display persistent neuromuscular deficits compared to skiers with no history of ACL injury7, 8, 9. ACL injury affects many elite ski racers2, and recent evidence demonstrates that, unlike in many other sports with poor outcomes after ACLR, elite alpine skiers not only return to sport after ACLR, but often go on to better performances than prior to injury4. This finding requires explanation and demands an increased emphasis on understanding the implications of ACLR on neuromuscular control strategies, such as preparatory quadriceps-hamstrings muscle activity.

the uninvolved limb and compared to skiers with no history of ACLR. This finding is insofar important as a skewed differential quadriceps-hamstrings muscle activity prior to landing from a jump, a common mechanism of ACL injury for skiers1, is a risk factor for ACL11. Whether this positive adaptation observed here protects against further ACL injury in the ACLR skier should be investigated in future studies. Additionally, ACLR and control group athletes had higher levels of preparatory quadriceps muscle activity with fatigue resulting in an elevated quadriceps-hamstrings co-activity difference. This highlights the relevance of employing specific training interventions to protect elite skiers against ACL injury in the fatigued state. While future research clearly is needed, specific training methods should target the rapid force producing capabilities of the hamstrings and engraining more fatigue resistant motor control strategies during jump landing. ∆

The main finding of this study was that the involved limb of ACLR skiers who successfully returned to sport displayed improved balance (i.e. more hamstring dominance) in the preparatory quadricepshamstrings co-activity levels compared to

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References Bere, T., Flørenes, T. W., Krosshaug, T., Haugen, P., Svandal, I., Nordsletten, L., & Bahr, R. (2014a). A systematic video analysis of 69 injury cases in World Cup alpine skiing. Scandinavian Journal of Medicine and Science in Sports, 24(4), 667–677.

Bere, T., Flørenes, T. W., Nordsletten, L., & Bahr, R. (2014b). Sex differences in the risk of injury in World Cup alpine skiers: a 6-year cohort study. British Journal of Sports Medicine, 48(1), 36–40.

Behrens, M., Mau-Moeller, A., Wassermann, F., Plewka, A., Bader, R., & Bruhn, S. (2015). Repetitive jumping and sprinting until exhaustion alters hamstring reflex responses and tibial translation in males and females. Journal of Orthopaedic Research, (November), 1687–1692.

Haida, A., Coulmy, N., Dor, F., Antero-Jacquemin, J., Marc, A., Ledanois, T., … Toussaint, J.-F. (2015).

Return to Sport Among French Alpine Skiers After an Anterior Cruciate Ligament Rupture: Results From 1980 to 2013. The American Journal of Sports Medicine.

Hewett, T. E. (2005). Biomechanical measures of neuromuscular control and valgus loading of the knee predict anterior cruciate ligament injury risk in female athletes: a prospective study. The American Journal of Sports Medicine, 33(4), 492–501.

Holsgaard-Larsen, a., Jensen, C., Mortensen, N. H. M., & Aagaard, P. (2014). Concurrent assessments of lower limb loading patterns, mechanical muscle strength and functional performance in ACL-patients A cross-sectional study. Knee, 21, 66–73.

Jordan, M. J., Aagaard, P., & Herzog, W. (2014).

A return to skiing envelope of function for anterior cruciate ligament reconstructed elite Alpine ski racers.

In E. Muller, J. Kroll, S. Lindinger, J. Pfusterschmied, & T. Stoggle (Eds.), Science and Skiing VI (pp. 187– 195). Salzburg: Meyer & Meyer Sport.

Jordan, M. J., Aagaard, P., & Herzog, W. (2015a).

Lower limb asymmetry in mechanical muscle function: A comparison between ski racers with and without ACL reconstruction. Scandinavian Journal of Medicine & Science in Sports, 25(3), e301–e309.

Figure 1: A comparison of the vastus-lateralis-semitendinosus difference (top panels) and the quadriceps-hamstring muscle activity difference (bottom panels) for the pre-landing phase across jump sets and limb status. A main effect was found for jump set [χ2(73.8), df = 3, P<0.0001] and limb status [χ2(12.1), df = 2, P<0.001] on the vastus-lateralis-semitendinosus difference. A main effect was also found for jump set on the quadriceps-hamstring difference [χ2(76.1), df = 3, P<0.0001]. Data is shown as the mean asymmetry index ± 95% confidence interval. ### Denotes significantly different from Set 1 [P<0.001]. ** Denotes significantly different from Uninvolved Limb [P<0.01]. † Denotes significantly different from Control Limb (P<0.05).

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Jordan, M. J., Aagaard, P., & Herzog, W. (2015b).

Rapid Hamstrings/Quadriceps Strength in ACLReconstructed Elite Alpine Ski Racers. Medicine and Science in Sports and Exercise, 47(1), 109–119.

Pujol, N., Blanchi, M. P. R., & Chambat, P. (2007). The incidence of anterior cruciate ligament injuries among competitive alpine skiers: a 25-year investigation.

The American Journal of Sports Medicine, 35(7), 1070–1074.

Zebis, M. K., Andersen, L. L., Bencke, J., Kjaer, M., & Aagaard, P. (2009). Identification of athletes at future risk of anterior cruciate ligament ruptures by neuromuscular screening. The American Journal of Sports Medicine, 37, 1967–1973.

Zebis, M. K., Bencke, J., Andersen, L. L., Alkjær, T., Suetta, C., Mortensen, P., Aagaard, P. (2011). Acute fatigue impairs neuromuscular activity of anterior cruciate ligament-agonist muscles in female team handball players. Scandinavian Journal of Medicine and Science in Sports, 21(6).

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Equipment Advances to Improve the lab-based Measurement of a BMX Sprint Start Authors: Jensen MJ1, 2, Sporer B1, 3, Wooles AL4, Klimstra MD1 Affiliation: 1Exercise Science, University of Victoria, Victoria, Canada; 2 Canadian Sport Institute Pacific, Victoria, Canada; 3 ReSync Consulting, Vancouver, Canada; 4 Cycling Canada, Vancouver, Canada

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he SRM PowerMeterTM is usually referred to as the ‘Gold Standard’ when it comes to measuring the power output of a cyclist and has been shown to be accurate to within manufacture’s specifications (±0.5% Science Model). However, a major limitation with the SRM PowerMeter TM is it does not measure instantaneous angular velocity of the crank throughout the pedal cycle, but rather only averages over one pedal revolution. The sport of BMX demands the generation of high power from stand-still, requiring the athlete to produce power at a high rate via large changes in angular velocity during just the first few (<6) pedal revolutions (0-240rpm). Thus, averaging angular velocity over one revolution does not provide the temporal resolution required to assess very small, but meaningful biomechanical metrics linked to performance. Further, there is a need to improve and expand on the metrics available for BMX sprint analysis.

Purpose:

Results:

To collect angular velocity for every 5° segment during a pedal revolution, along with torque data. This will 1) Create a more accurate pedal power profile to determine peak power for any part of the pedal revolution and 2) Create the opportunity to define new performance metrics.

The SRM PowerControlTM readings were on average 7.7% (SD: ±3.2%) lower than the custom device. The collection rate of the PowerControl (0.1s vs 0.5s) had no effect on improving accuracy, 8.1% and 7.3% respectively. The gearing of the SRM ergometer had an effect on the accuracy of the power reading, with gear 1 being 11.1% lower and gear 4 being 4.1% lower. Gear 1 has the least resistance and therefore the greatest increase in angular velocity (rpm).

The new metrics that were defined were, Time to Kink (time to travel 5.4m), Time to 20m, 360 Peak Watts (Time, Location), Displacement, Start Angle, Peak Cadence, Absolute peak Watts (5° segment), Individual revolution wattage, and pedal smoothness. Along with these metrics, we were able to accurately plot the power output for each 5° segment.

Methods: A custom SRM sensor add-on was developed to measure angular velocity and torque every 5° of a pedal rotation. Data was collected from the top male BMX riders in Canada. Subjects performed standing starts in a lab (mimicking the track starts) on a modified SRM ergometer. In total, 63 starts consisting of 4-6 pedal revolutions were analyzed, with 51 being used to compare to SRM PowerControlTM data.

Trials were performed in varying gears, ranging from 1 to 4.

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Matt Jensen holds a BSc in Kinesiology/Biology and is currently pursuing a doctorate in Biomechanics at the University of Victoria. Matt is an ongoing consultant for performance analysis and technology innovation with CSI-Pacific and B2ten working with cycling based disciplines.

Matt is a former world-class rower and is an assistant coach and physiologist for the UVic Men’s rowing team.

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Conclusions:

Figure 1: Percentage difference between SRM ergometer power output reading using a constant angular velocity versus custom device using 5 degree resolution. SRM power output readings are either 0.5 second (blue) or 0.1 second (orange). Comparison was done in varying gears on the SRM ergometer, Gear 1 (least resistance) to Gear 4 (most resistance)

This study confirms the limitation of the SRM PowerMeterTM during a BMX start when it assumes a constant angular velocity to calculate power. These new BMX start-specific metrics explicit to 5° pedal segment measurements provides much improved measurement density and increases knowledge of the explosive start. Also provides an opportunity to precisely measure an athlete’s progress by creating accurate measures that can be compared throughout their careers to evaluate injury state and performance improvement. Along with BMX, this technology could eventually be used for other cycling disciplines where sprints occur. ∆

Figure 2: Comparison between SRM Powercontrol (black) and custom device (red) power readings versus time. Custom device allows to identify precise location of power application.

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Validation of an evaluation protocol combining isokinetic strength testing, electromyography of the shoulder and of a novel statistical analysis method Authors: Sylvain Gaudet, M.Sc, Jonathan Tremblay, PhD, Mickael Begon, PhD Affiliation: Department of Kinesiology, University of Montreal

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hronic shoulder injuries represent a significant challenge to swimming performance given the important contribution of the upper limb during propulsion (Wanivenhaus, Fox, Chaudhury, & Rodeo, 2012). Both strength imbalance between internal and external rotators of the shoulder and lack of dynamic muscle control of the scapula have been suggested as main factors explaining the occurrence of shoulder injuries (Wanivenhaus et al., 2012). Yet, few prospective studies were carried out to prove cause-effect relationships.

Better understanding of the long-term shoulder adaptations to swimming would help prevent and manage chronic shoulder injuries and could therefore improve performance.

The objective of this study was to develop a reliable (within- and between-session) evaluation protocol to use for longitudinal shoulder injury follow-up of swimmers. A secondary objective was to identify, in a population of able-bodied participants, spatial differences in the electromyography (EMG) signal related to the three following factors: fatigue state (pre-post), velocity (60-240°/s), and contraction type (concentric-eccentric).

Methods Eighteen participants (24.9 ± 3.3 years, 67.93 ± 9.84 kg, 173.5 ± 9.8 cm) volunteered to participate in this study after signing an informed consent. Subjects were all physically active adults and reported no shoulder injury at the time of evaluation.

Participants’ right shoulder was evaluated on a Physiomed CON-TREX® MJ isokinetic dynamometer on two separate occasions at 5-7 days intervals to assess reliability of the protocol. The protocol consisted of a set of concentric and eccentric shoulder internal and external rotations at velocities of 60 and 240°/s (see Table 1). The testing speed order was randomized across subjects and for each speed, the order of contraction was: internal concentric (IR), external concentric (ER), internal eccentric (IX) and external eccentric (EX). For each contraction, three repetitions were completed. The set was repeated following a 50-repetition concentricconcentric fatigue protocol at 240°/s.

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Pre-Fatigue

Fatigue Set

Post-Fatigue

3 reps each @ 60°/s IR, ER, IX, EX

50 IR-ER cycles @ 240°/s

3 reps each @ 60°/s IR, ER, IX, EX

3 reps each @ 240°/s IR, ER, IX, EX

3 reps each @ 240°/s IR, ER, IX, EX

Table 1: General outline of the evaluation protocol On the second testing day, the protocol was repeated while the activity of 11 muscles acting at the shoulder was recorded through surface (Marion, 2015) and fine-wire (Gerdie et al., 2000) EMG (see Table 2 and Fig. 1). Surface EMG sensors were placed according to SENIAM recommendations

(see Figure 1) while fine-wire EMG insertion was based on the works of Kadaba et al.

(1992) and Morris et al. (1998). EMG signal for each muscle was normalized against maximum EMG activity recorded during 15 different maximal voluntary isometric contractions (MVIC) (Marion, 2015).

Surface EMG

Intramuscular EMG

1) Pectoralis Major

5) Lower Trapezius

9) Supraspinatus

2) Latissimus Dorsi

6) Posterior Deltoid

10) Infraspinatus

3) Upper Trapezius

7) Medial Deltoid

11) Subscapularis

4) Middle Trapezius

8) Serratus Anterior

Table 2: List of muscles instrumented with EMG

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Fig.1: Placement of the EMG sensors.

Intraclass correlation coefficients (ICC) and typical error of measurement (TEM) of peak torque were calculated to assess withinand between-session reliability (Hopkins, Schabort, & Hawley, 2001). Statistical parametric mapping (SPM) analysis using a three-way ANOVA model (Contraction x Speed x Fatigue) was performed on the normalized EMG curve of each muscle to identify temporal differences in muscle activation between testing conditions (Pataky, 2010).

Results Mean peak torque, inter-session change in mean, TEM and ICC for the each testing condition are presented in Table 3. The mean peak torque measured on the two separate testing days differed by less than 5% (0.7 - 4.3%). Within- and betweensession ICCs were between 0.92 and 0.99. In addition, the TEM, expressed as a coefficient of variation (CV), was between 6.7 and 14.5%.

Table 3: Mean torque, changes in mean, typical errors and intraclass correlation coefficients for the various types of contractions of the shoulder

TEM (N*m) 3.84 2.33 7.14

TEM (%)

51.0 ± 22.4

Change in mean (%) 3.4 0.9 2.6

33.0 ± 10.7

32.5 ± 9.9

-1.3

3.09

10.2

0.92

0.94

37.1 ± 17.0 21.4 ± 9.6 48.7 ± 21.8 31.3 ± 11.9

37.0 ± 16.1

-0.3

2.17

6.7

0.98

0.98

21.6 ± 8.8

1.0

2.05

12.2

0.94

0.97

48.0 ± 18.8

-1.4

5.40

10.7

0.94

0.97

31.5 ± 10.4

0.5

2.94

10.2

0.94

0.94

Mean Torque ± SD (N*m) Day 1

Mean Torque ± SD (N*m) Day 2

IR60

38.2 ± 17.5

39.5 ± 17.8

ER60

25.9 ± 10.6

26.1 ± 9.9

IX60

49.7 ± 22.6

EX60

IR240 ER240 IX240 EX240

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8.9 9.3 14.5

BetweenWithinsession ICC session ICC 0.97 0.98 0.96 0.99 0.92 0.98

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The three-way ANOVA SPM analysis revealed significant effects for Contraction, Speed, and Contraction x Speed on the EMG signal recorded for all 11 muscles, while Fatigue had no effect. Comparing concentric and eccentric efforts, post hoc tests identified significant temporal differences in the EMG activity of pectoralis major, latissimus dorsi and subscapularis muscles during internal rotation and for all but pectoralis major muscles during external rotation. Generally, differences were seen in the pre-activation region, with a notable earlier rise of activity seen for eccentric contraction and for the fastest speed. Differences were also found in the last 15-30% of the contractions, where EMG activity during concentric efforts tended to be higher than during eccentric efforts for most muscles. Figure 3 illustrates the SPM post hoc analysis process for lower trapezius muscle in external rotation.

Fig.2: Group mean normalized EMG activity for concentric (ER) and eccentric (EX) external rotation efforts at 60 and 240 °/s.

Sylvain Gaudet is a PhD student at Université de Montréal.

His thesis focuses on the evaluation, prevention and rehabilitation of chronic shoulder injuries in aquatic sports.

Sylvain obtained his master’s degree in Performance Analysis in Sports from Otto Von Guericke University, Germany. He has done some work as performance analyst with Synchro Canada and as strength and conditioning coach with the Canadian Team Handball Federation. He is still an active elite athlete, competing on the senior national handball team for the last 8 years.

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Fig.3: Example of SPM analysis post hoc tests results for the lower trapezius during external rotation efforts. The 125 continuum positions represents each time points of the normalized cycle (from -25 to 100% of contraction). Shaded grey zones represent sections of the EMG continuum where the SPM test has reached the critical t threshold, indicating significant difference between the compared conditions. For example, top right graph shows that EMG activity of the lower trapezius during ER60 compared to EX240 is significantly lower in the first 35 time-points (-25 to 10% of the normalized cycle), but significantly higher in the last 35% of the normalized cycle.

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Discussion The Physiomed CON-TREX® MJ isokinetic dynamometer delivered reliable measurements of shoulder internal and external rotation torque at 60 and 240°/s.

In addition, the SPM method was able to identify temporal differences in muscle activation between the different types of contraction and velocities.

The calculated ICCs and TEMs were excellent and similar or higher than values reported in the literature on other machines.

In their systematic review, Edouard et al.

(2011) reported ICCs of 0.09 to 0.99, with the seated position with 45° of shoulder abduction in the scapular plane being the most reliable position to test the shoulder rotator muscles, which was the same position used in the present study. The TEMs (6.7-14.5%) for the various testing conditions were also similar to those reported by Edouard et al. (2013) (7.714.5%) who tested isokinetic shoulder rotator strength on a Biodex dynamometer.

Given that elite athletes tend to show less variability in performance (Malcata & Hopkins, 2014), it could be expected that the measures of reliability would improve with an athletic population, thus increasing sensibility to change.

The advantage of SPM method to interpret EMG signal is its ability to identify temporal differences between conditions that would not be possible using the traditional statistical analysis of scalar (Robinson, Vanrenterghem, & Pataky, 2015). For instance, Kellis & Baltzopoulos (1998) found that normalized integrated EMG of agonists and antagonist of the knee were lower during eccentric compared to concentric contractions. In comparison, our results showed that, during shoulder internal and external rotations, eccentric EMG activity tended to be higher in the early phase of the movement yet lower toward the final 30% of the normalized cycle. The absence of Fatigue effect on the EMG series was a bit surprising. Other EMG variables, such as mean frequency, may be better fatigue indicators than normalized activity as suggested by Gerdle et al. (2000).

In conclusion, our reliable protocol along with the SPM method can be of great use for longitudinal follow-up of swimmers aiming to prevent shoulder injuries. ∆

References Edouard, P., Codine, P., Samozino, P., Bernard, P.-L., Hérisson, C., & Gremeaux, V. (2013). Reliability of shoulder rotators isokinetic strength imbalance measured using the Biodex dynamometer.

Journal Sci Med Sport, 16(2), 162-165.

Edouard, P., Samozino, P., Julia, M., Gleizes Cervera, S., Vanbiervliet, W., Calmels, P., & Gremeaux, V. (2011). Reliability of isokinetic assessment of shoulder-rotator strength: a systematic review of the effect of position. J Sport Rehabil, 20(3), 367-383.

Gerdle, B., Larsson, B., & Karlsson, S. (2000). Criterion validation of surface EMG variables as fatigue indicators using peak torque: a study of repetitive maximum isokinetic knee extensions. Journal of Electromyography and Kinesiology, 10(4), 225-232.

Hopkins, W. G., Schabort, E. J., & Hawley, J. A. (2001). Reliability of power in physical performance tests. Sports Medicine, 31(3), 211-234.

Kadaba, M. P., Cole, A., Wootten, M. E., McCann, P., Reid, M., Mulford, G., . . . Bigliani, L. (1992). Intramuscular wire electromyography of the subscapularis. J Orthop Res, 10(3), 394397.

Kellis, E., & Baltzopoulos, V. (1998). Muscle activation differences between eccentric and concentric isokinetic exercise. Med Sci Sports Exerc, 30(11), 1616-1623.

Malcata, R. M., & Hopkins, W. G. (2014). Variability of competitive performance of elite athletes: a systematic review. Sports Medicine, 44(12), 1763-1774.

Marion, P. (2015). Proposition de combinaisons optimales de contractions volontaires maximales isométriques pour la normalisation de 12 muscles de l’épaule. (Maîtrise), Université de Montréal, Montréal.

Morris, A. D., Kemp, G. J., Lees, A., & Frostick, S. P. (1998). A study of the reproducibility of three different normalisation methods in intramuscular dual fine wire electromyography of the shoulder.

Journal of Electromyography and Kinesiology, 8(5), 317-322.

Pataky, T. C. (2010). Generalized n-dimensional biomechanical field analysis using statistical parametric mapping. J Biomech, 43(10), 1976-1982.

Robinson, M. A., Vanrenterghem, J., & Pataky, T. C. (2015).

Statistical Parametric Mapping (SPM) for alpha-based statistical analyses of multi-muscle EMG time-series. Journal of Electromyography and Kinesiology, 25(1), 14-19.

Wanivenhaus, F., Fox, A. J. S., Chaudhury, S., & Rodeo, S. A. (2012). Epidemiology of injuries and prevention strategies in competitive swimmers. Sports Health, 4(3), 246-251.

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CANADIAN SPORT INSTITUTE PACIFIC

THREE MAJOR CAMPUSES OFFERING WORLD CLASS PROGRAMMING

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he Canadian Sport Institute Pacific offers programs and services throughout British Columbia through a unique regional network. With world class facility-based campuses in Victoria (at the Pacific Institute for Sport Excellence), Richmond (at the Richmond Olympic Oval) and Whistler (at the Whistler Athletes’ Centre), and six PacificSport Centres across the province, athletes and coaches have excellent resources throughout BC. Over the past five years, CSI Pacific has been more focused than ever on identifying and developing up and coming Canadian athletes and coaches. With the support of Own The Podium (OTP), the Province of British Columbia, and our National Sport Organization (NSO) and Provincial Sport Organization (PSO) partners, we have created some groundbreaking programming in Canada.

The NextGen program focuses on athletes and teams 8-5 years from the podium as identified by the sport specific Podium Pathway and Gold Medal Profile. These athletes and teams represent the next generation of Olympic and Paralympic medallists. Currently there are five fully funded sports in the program with an in house CSI Pacific coach – cycling, rowing, swimming, luge and moguls. In addition, there are six other sports running NSO driven NextGen programming with CSI-Pacific support: snowboard, ski cross, athletics, para alpine, para athletics and wheelchair rugby.

In addition to the NextGen programming, CSI Pacific operates the Canadian Sport School, an important initiative delivered in partnership with the PacificSport Centres. With campuses located in Victoria, Kelowna, Prince George

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and Fort St. John this program provides athletic and academic support for secondary student athletes who are balancing their educational and high performance training demands.

The Canadian Sport School helps to alleviate the pressures experienced by high performance secondary school athletes and ensure that our future Olympians and National Team members have all the skills and resources needed to continue to progress as high performance athletes, while excelling both on the playing field and in the classroom.

The IGNITE Athlete Development Program goes hand in hand with the Canadian Sport School framework. IGNITE targets eligible athletes between the ages of 14-17 and introduces young athletes who are targeted by their Provincial Sport

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Organization to a high-performance lifestyle by improving their athleticism, physical literacy and fitness through a multi-sport training program which is complementary to their current sportspecific practice and competition schedules. This program is run in select locations across BC and often in conjunction with Canadian Sport School.

Along with athlete-centered programming, CSI Pacific has also launched an exciting new graduate program at the University of British Columbia. The UBC Graduate Certificate in High Performance Coaching and Technical Leadership is a one-year, 12 credit specialized program for experienced sport coaches and technical managers who are looking to advance in their careers. This program will provide credit toward the NCCP Advanced Coaching Diploma and a UBC Master’s degree.

Along with supporting up and coming athletes and coaches, CSI Pacific continues to lead targeted Innovation and Research (I&R) projects with a direct impact on Canada’s medal performances.

These projects are conducted in collaboration with the University of Victoria, the University of British Columbia, Camosun College, and with numerous international institutions. The CSI Pacific I&R staff features five PhDs and who are Certified Exercise Physiologists (CEP) and Certified Strength & Conditioning Specialists (CSCS). On an annual basis, the I&R team publishes 10 to 15 peer-reviewed scientific publications and also offers “for-hire” research experiences with for-profit companies. ∆

“

Now that our facilities are well established across the province, it has been really exciting to focus on programming for athletes and coaches,” said Wendy Pattenden, CEO Canadian Sport Institute Pacific. “From identifying the NextGen to ensuring athletes and coaches have the proper training through Canadian Sport School, IGNITE and graduate coaching programs, we are working to ensure the high performance pathway is thriving in Canada. On top of this, of our Innovation and Research team continues to push the boundaries of sport performance and ensure we are building champions who can compete and win against the best in the world.

”

Canadian Sport Institute Pacific www.sirc.ca

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A DECISION-MATRIX FOR DETERMINING RISK IN TALENT SELECTION

Joseph Baker

Professor, York University

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Les Gilson

Atlantic High Performance Manager, Rugby Canada

Nick Wattie

Assistant Professor, University of Ontario Institute of Technology

thlete development is a heavily nuanced, extended process that typically involves a series of stages (or selections). These selections ultimately determine who is able to move on to the upper levels of competition and coaching. While athlete selection decisions form the basis of athlete development systems worldwide, the evidence for their efficacy is limited and existing evidence suggests the accuracy of talent identification is weak (Koz et al., 2012).

Our team has a long-standing program of research examining the process of athlete development and the value of talent identification (see Baker, Cobley & Schorer, 2012; Baker, Cobley, Schorer & Wattie, in press) in the hopes of understanding how to improve athlete development systems to ensure greater success at lower costs (i.e., improved efficiency: see Wattie & Baker, in press). Even though the notion of talent (i.e., that some people can be predisposed towards exceptional levels of performance in a domain) makes sense based on basic evolutionary theory (i.e., that genetic diversity is the mechanism of species evolution), as of yet there are no valid indicators of sporting talent. As a result, those involved with athlete selection are faced with the difficult

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job of identifying potential in the absence of any valid measures of its existence. As a result, they typically have to infer talent (i.e., potential) from current levels of performance.

This can be problematic since the factors determining performance at lower levels of development are usually less useful (or even irrelevant) for predicting performance at the adult, high-performance level.

Consider height in basketball, for example.

At lower levels of skill, taller players typically have an advantage and so height predicts performance, but at the elite (e.g., NBA) level nearly all players are above average in height so this variable no longer discriminates the successful player from the less successful one (i.e., it’s no longer predictive).

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Because relying on current levels of performance to reflect potential is inherently flawed practitioners are at risk in several areas. Most relevant to our discussion are the risks associated with different decisions along the athlete development pathway.

The matrix shown in Figure 1 reflects the different types of risk associated with common decisions about athlete selection.

For example, athletes in the grey and green boxes may not be a problem because those who don’t have high enough performance will be removed from the system while those with superior performance will stay in. Conversely, athletes in the blue boxes represent moderate risk because a) they ultimately represent ‘average’ performance

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which will not be good enough to attain the levels required for true ‘elite’ performance (i.e., average won’t cut it) and b) they have the potential to ‘clog’ the system taking spots from those with higher potential. Importantly, the highest levels of risk are the green boxes since they either represent highest levels of potential that may be lost if coaches focus too much on performance as an indictor of value (boxes 7 and 8) or they reflect those with initial high levels of performance but low long-term potential. This latter group also has the potential to take spots that would be

better suited to athletes with higher potential for future performance.

In science, researchers often have to consider the costs of a Type I versus a Type II error. Type I errors are ‘false positives’ in our discussion represented by selections where coaches think potential is there when it isn’t. Type II errors are those where coaches de-select someone because they think they aren’t talented when they are. It would be worthwhile for coaches and administrators to also consider ‘which type of error are you

most comfortable with?’. Maximizing limited athlete development resources involves the efficient use of both athlete resources (i.e., participants) and the possible factors limiting future performance. As our understanding of the latter continues to develop, we should increasingly strive toward not neglecting our richest resource, youth with the drive and desire to practice the long, hard hours of training necessary to reach the upper echelons of sport. ∆ References Baker, J., Cobley, S., & Schorer, J. (2012).

Talent identification and development in sport: International perspectives. Routledge/Taylor and Francis.

Baker, J., Cobley, S., Schorer, J., & Wattie, N. (in press). The Routledge handbook of talent identification and development in sport.

London: Routledge.

Koz, D., Fraser-Thomas, J. & Baker, J. (2012).

Accuracy of professional sports drafts in predicting career potential. Scandinavian Journal of Medicine and Science in Sports, 22, e64-e69.

Wattie, N., & Baker, N. (in press). An uneven playing field: Talent identification systems and the perpetuation of participation biases in high performance sport. In R. Dionigi and M. Gard (Eds.), Sport and physical activity across the lifespan: Critical perspectives. Macmillan.

Figure Caption: A risk matrix for talent identification decisions with grey boxes representing low-risk, blue medium-risk and green high-risk decisions. www.sirc.ca

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PEAK HEIGHT VELOCITY & THE DEVELOPING ATHLETE What’s new in the research?

Nancy Rebel, MLIS Director of Content Development, SIRC

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ne of the over-arching premises of long-term athlete development is that one size does not fit all, recognizing that an athlete’s chronological age does not necessarily match up with their developmental age. The premise of the model is to balance training load and competition based upon physiological assessments of maturation rates of children and adolescents by using measures such as peak height velocity (PHV). PHV estimates the timing of peak growth rates, the adolescent growth spurt, and may allow coaches and trainers to adapt training protocols to match with developmental and maturation stages of young athletes more appropriately.

Why is determining PHV so important?

During PHV, the limbs and the spine may be growing at different rates throwing off athlete coordination and performance. Determining PHV can identify peak trainability periods by providing information on athletes’ energy systems and the central nervous system.

Knowing the PHV of an athlete allows training, competition and recovery strategies to be design to capitalize on the best time for adaptation to stamina (endurance), strength, speed, skill and flexibility training (Webb).

Injury risk is also of great concern at this time (see Sidebar for more information).

What does the latest research say?

A variety of studies published since 2014 have taken a look at a number of different areas of athlete development and its relation to PHV. A review of research by Melina et al (2015) found the following general observations on physiological changes around PHV: • growth spurts in lower body dimensions occur, on average, before PHV, in both sexes 18

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• spurts in body weight, lean tissue mass, bone mineral content, and upper body dimensions occur after PHV in both sexes • data for speed and flexibility suggested peak gains before PHV in boys • tests of strength and power attained peak gains after PHV • peak velocity in maximal aerobic capacity (VOmax) occurred coincident with PHV in both sexes While many studies have examined speed development relative to chronological age, Myers et al (2015) has explored spurts in sprint performance relative to PHV. Their study examined the natural development of the mechanical features of sprint performance (maximal speed, stride length (SL), stride frequency (SF), flight time (FT) and contact time (CT)) in relation to maturation during a 30m sprint in boys.

According to the authors “maximal sprint speed appears to develop around and post-PHV as stride frequency and contact time begin to stabilize, with increases in Français

maximal sprint speed in maturing boys being underpinned by increasing stride length”.

This research emphasizes the importance of the time around PHV in terms of speed development in boys.

Rumpf et al has performed a set of studies published in 2015 around sprint speed and resisted sprint training relative to maturing youth and PHV. The following studies relate their findings: • Resisted sled towing, while commonly studied in adult populations, is not as common in youth-based research in terms of how the load may affect sprint kinematics. Rumpf et al (2015) hypothesize that differences in maturation around PHV in boys may affect force production and therefore running speed, and that running kinetics and kinematics also differ relative to maturity status thereby affecting loading of athletes. The research found that “sprint performance decreased on average by -1,5% and 1% for each additional percent of body mass load, for pre- and mid/post-PHV participants respectively”, older and more www.sirc.ca

Preventing Injuries in Adolescent Athletes Michelle Caron Adolescent growth spurts can be a frustrating time for a young athlete, where a once agile youth can suddenly seem uncoordinated and a bit awkward. It can be difficult for athletes to adapt to these changes, and many experience a decline in core strength, balance, and often find themselves getting injured more regularly. The good news is this decline in performance is often short-lived and a normal phase of growing up.

mature athletes were less affected by the same relative loads. Maturation specific regression equations were generated to predict the effects of load on the sprint performance of youth athletes, the effect of load magnifies at heavier relative loads.

The authors supposed that hormonal outflow occurring during puberty affects body mass and subsequently muscle mass and relative strength and power in most mid/post-PHV participants.

• In a second study, Rumpf et al studied kinetics and kinematics as related to maximum sprint velocity relative to maturity status in boys. The findings showed that the greatest magnitude of changes occurred pre- to mid-PHV leading to the suggestion that sprint training should be maximized during this time frame. They also suggest that training be kinematic/technique and coordination focused due to the maturity stage of the group.

In contrast, Meylan et al (2014) looked at how maturity status (measured by PHV) affected strength training and detraining in relation to performance in boys. Their findings showed that strength training was more generally more beneficial to postPHV boys than pre-PHV, with the greater changes appearing for mid- to post-PHV boys. At the detraining period, “the pre-PHV www.sirc.ca

group showed greatest loss of strength and power, the post-PHV group showed some loss of sprint performance, but all groups maintained or improved jump length”. These are areas where maintenance training will need to concentrate.

A final study took a look at how PHV affected injury risk in girls. Knee injuries have been commonly associated with sport in general and with female sport in particular.

Hewitt et al (2015) studied knee abduction moment (KAM) in adolescents and found differences between the genders during and following PHV which seems to contribute to the higher risk of knee injury in pubertal girls. Increased KAM was found to be an important identifier in athletes at increased risk of ACL injury. Preventative measures include neuromuscular training designed to decrease KAM when instituted just prior to or during PHV. Taking a look at all these areas of study examined in the last few years – physiological adaptations, speed, strength, injury risk – it is easy to see how clearly PHV and maturation has a significant impact on adolescent athletes. Having PHV measurements integrated into coaching and training plans can create significant benefits to building effective and targeted athletic performance development. ∆ Français

The injuries a teen can experience in sport are just a varied as the sports themselves, with contact and overuse injuries being the most common and well-known. Recognition of the many changes happening within a teen athlete, and finding ways to work with and around them, is one of the many aspects of a coach’s job. Many experts agree that running and jumping technique definitely play an important role in injury prevention. Below are a few suggestions a coach may wish to include when training young athletes: • Incorporate exercises that focus on improving balance, such single vertical leg jumps or squats, and leg swings.

• Try functional bodyweight training to increase strength, for example, lunges, press-ups, burpees, etc.

• Increase overall conditioning.

• Focus more on agility training, i.e., footwork.

• Ensure the athlete has all the equipment they need and that it is properly fitted for them.

• Stress the importance of cross-training.

Participating in multiple sports and activities creates a well-rounded athlete and is one of the best ways to prevent overuse injuries.

Keep in mind that there is no way to achieve 100% injury prevention. Rapid growth can often make young bodies feel awkward or off-balance. When you mix that up with a fast-paced, intense game of basketball or soccer, for example, accidents can happen.∆ Selected References (Contact SIRC for a full list)

Hewett T, Myer G, Kiefer A, Ford K. Longitudinal Increases in Knee Abduction Moments in Females during Adolescent Growth. Medicine & Science in Sports & Exercise. December 2015;47(12):2579-2585.

Malina RM, Rogol RD, Cumming SP, Coelho e Silva MJ, Figueiredo.

Biological maturation of youth athletes: assessment and implications.

British Journal of Sports Medicine. 2015; 49(13):852-859.

Meyers R, Oliver J, Hughes M, Cronin J, Lloyd R. Maximal Sprint Speed in Boys of Increasing Maturity. Pediatric Exercise Science.

February 2015;27(1):85-94.

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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.

Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals: a systematic review Behm D.G., Blazevich A.J., Kay A.D., McHugh M. Applied Physiology, Nutrition, and Metabolism. 2016;41(1):1-11.

Reviewed by Eugene Liang Historically, stretching, in its’ numerous incarnations, has been a key component of athletic training, rehabilitation and racing.

However, the efficacy of the stretching on performance and injury prevention has been debated for years; with the pendulum swinging numerous times from one side to the other and back. Agreement on the topic of stretching lies in the types most commonly used; static stretching (SS), proprioceptive neuromuscular facilitation (PNF) and dynamic stretching (DS). In their systematic review Behm et al. the effectiveness of SS, DS and PNF on performance, ROM and injury prevention are investigated. The literature revealed that small to moderate performance changes were occurring with all three types post implementation within a warm up protocol.

These changes were attributed to the impact of any dynamic activity. ROM changes were also

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seen from all three types of stretching. However, ROM changes were attributed reductions in muscle and tendon stiffness as well as improved stretch tolerances from neural adaptations.

Clinically, the review suggests that incorporating stretching protocols in warm up has no ill effect on performance and can impact ROM in the short term. However, adding dynamic activity immediately post stretching can play a larger role in performance than stretching alone. ∆

Effect of Long-Term Isometric Training on Core/ Torso Stiffness Lee B. & McGill, S. Journal of Strength and Conditioning Research. 2015;29(6):1515-1526.

Reviewed by Jeremiah Barnert Typical athletic training involves developing core strength to induce long term strength, speed and endurance adaptations but little is know if the effect is long lasting. Although core stiffness enhances performance traits, controversy exists regarding the effectiveness of isometric and dynamic core training methods. To evaluate the effects of long term adaptations to isometric core training Lee and McGill (2015) performed a repeated-measures design study that examined isometric and dynamic core methods between naïve and savvy athletes across a 6 week period. Passive and active stiffness were recorded with a “frictionless” and “quick release” apparatus developed by Brown and McGill (2005) and an EMG unit in conjunction with torso kinematics. The primary finding of this study was that isometric training was superior to dynamic training to enhance core stiffness.

Isometric training leading to a development of core stiffness while minimizing imposed loads to the spine could potentially free up capacity to put towards sport practices. Exceeding tissue tolerance by loading the athlete too frequently or too greatly increases the risk of injury, therefore, the use of isometric training may place a further emphasis on other strength qualities that may be identified as key performance indicators. ∆

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Psychological skills training for athletes with disabilities Hanrahan, S.J. Australian Psychologist. 2014;50(2):102-105.

Reviewed by Leslie Toogood This article provides a summary of information from both research and applied practice for working with athletes with disabilities.

Considerations are provided for athletes with physical disabilities (e.g., spinal cord lesions, cerebral palsy, and amputations), intellectual disabilities, and sensory impairments (e.g., hard of hearing, deafness, visual impairment and blindness). Primary areas considered include relaxation, imagery and communication.

Highlights from the section on athletes with physical disabilities include elimination of the tension component of progressive muscle relaxation for athletes with cerebral palsy, and allowing athletes with muscular loss or amputation to try both adapted and standard autogenic scripts. Furthermore, abdominal breathing can be beneficial even for athletes who have no control over abdominal muscles.

In the section on intellectual impairments, practitioners were encouraged to work through biases and to use patience and repetition during service provision. For athletes with sensory impairment, it is important to assess the level of impairment and to clarify the best method for gaining attention when working with these athletes. Several other recommendations were included throughout this article. In the closing section, the author reminds us that the work often does not involve the disability; but the consultant should be open and comfortable discussing the disability if the athlete brings this up in conversation. They also emphasize that working with this population may require you to be creative and can definitely enhance a consultants overall communication skills, which is beneficial regardless of population with whom a consultant works. Notably, the author states that athletes with disabilities are often more appreciative of support staff than their ablebodied peers. ∆

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Wearable inertial sensors in swimming motion analysis: a systematic review.

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

de Magalhaes FA, Vannozzi G, Gatta G, Fantozzi S. Journal of Sports Sciences.

2015;33(7):732-45.

Reviewed by Mathieu Charbonneau This paper reviews different applications using IMUs in swimming for 15 years.

IMU refers to Inertial Measurement Units, this means sensors reacting to changes in state of motion (accelerations and rotations).

The review addresses five questions: (1) What are the applications for swimming motion analysis?

(2) What type of sensor was used?

(3) Where were the sensors attached?

(4) How were the experiments conducted?

(5) How was the performance evaluated?

In summary, sensors will tell what they are measuring and this depends on where they are attached to the body!

The main limitation of IMU is that 3D motion description is not accurate.

However, the signal is rich in terms of event detection and temporal information and this can lead to swimming phases, style, expertise, fatigue, coordination and velocity profiles analysis.

The article concludes on practical applications: • Inertial sensors (accelerometers and gyroscopes) are reliable tools to support performance assessment in sports.

• Sport biomechanists can incorporate basic metrics used by coaches and propose sensitive variables through data analysis.

• This swimmer-centric monitoring technology increases the amount of information available and allows to continuously analyse and monitor the whole swimming trial without spatial limitation (technical modifications with fatigue can be evaluated).

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Periodization Training The HIIT Advantage: In Pursuit of for Sports 3rd Edition. High-Intensity Excellence 5th Workouts for Edition.

Bompa, T. and Buzzichelli, Women.

C. (2015). Windsor, Ontario: Human Kinetics Lewis-McCormick, I. (2016). Windsor, Ontario: Human Kinetics

Orlick, T. (2016).

Windsor, Ontario: Human Kinetics

This knowledge can be exported to all cyclical sports to quantify the amount & frequency of movements, phases of movements, global output (intensity & directions of accelerations), timing of events and more. ∆ Limitations of Current AHA Guidelines and Proposal of New Guidelines for the Preparticipation Examination of Athletes Dunn T.P. Pickham D. Aggarwal S. Saini D. Kumar N. Wheeler M.T. Perez M. Ashley E. Froelicher V.F. Clinical Journal of Sport Medicine. 2015;25(6):472-477.

Reviewed by Paddy McCluskey This is a recent article from the CJSM regarding potential changes to cardiac screening. It is an important article as it continues the extensive body of work that is trying determine an effective cardiovascular screening tool for athletes, given the low rate of cardiac incidents (1 in 200 000) but the devastating consequences when an athletes dies from sudden cardiac death. The article suggests a new 12 component screening tool; 8 questions on personal history of potential cardiac related symptoms, 3 questions regarding family history and 1 physical exam finding. This new screening tool still needs to be validated but could represent an important step forward in this area. ∆

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High-Powered Plyometrics 2nd Edition.

Radcliffe, J.C. and Farentinos, R.C. (2015). Windsor, Ontario: Human Kinetics

Dynatomy with Web Resource: Dynamic Human Anatomy.

Whiting, W. and Rugg, S. (2015). Windsor, Ontario: Human Kinetics

Increasing protein distribution has no effect on changes in lean mass during a rugby preseason MacKenzie-Shalders, K.L.; King, N.A; Byrne, N.M; and Slater, G.J. International Journal of Sport Nutrition and Exercise Metabolism.

[Ahead of Print]

Reviewed by Erik Sesbreno, RD Many athletes and coaches are interested in ways to augment lean mass as a way to improve performance. In practice, the time allocated to build muscle could be restricted by the need to manage other training priorities or the competition schedule. Consequently, dietary strategies that may influence gains in lean mass has become an important topic.

MacKenzie-Shalders, et al. used a 6 week crossover design to compare 4 and 6 protein feedings on the rate of change in lean mass in elite male rugby players undertaking a resistance training program in the preseason.

Subjects received a high biological value (HBV) protein supplement (22 g whey protein) immediately after training and with main meals (bolus condition) or between meals (frequent condition). Twenty-four hour recalls were conducted weekly to monitor dietary intake.

Aside from instructing athletes to consume a minimum of 20g of HBV protein at their main meals (breakfast, lunch and dinner) and advising

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them to limit foods and fluids high in HBV protein, except for the supplement, between meals; investigators did not apply additional conditions to nutrient formulation of daily meals.

In the end, differences in lean mass gains assessed by dual energy x-ray absorptiometry were not observed. The lack of dietary controls may have introduced other nutritional factors that potentially augmented adaptation.

Despite credible physiological mechanisms for increasing protein distribution to promote muscle protein synthesis, the increase from 4 to 6 feedings daily does not appear to provide extra benefits to lean mass gains in male team-sport athletes. Nevertheless, there may be benefits to increasing protein intake distribution in situations that are less than ideal for muscle building.

Additional research is needed to determine if the reported outcome would apply to females, vegetarians, aging athletes and those training in negative energy balance. ∆

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Current Scientific Evidence for a Polarized Cardiovascular Endurance Training Model Hydren, J.R., Cohen, B.S. Journal of Strength and Conditioning Research. 2015;29(12):35233530.

Reviewed by Scott Maw Planning and distribution of an athlete’s training load is one of the most important tasks of a coach or sport scientist. Part of the challenge is to apply enough training so as to elicit optimal gains in fitness and performance, while avoiding injury or undue fatigue which could lead to non-functional overreaching or over training. In recent years sport scientists have been exploring the effectiveness of a novel training model termed Polarized Training. In this model the majority of training is conducted at intensities below the aerobic threshold or above the anaerobic threshold while avoiding, or significantly reducing, the volume of training conducted between these two thresholds. In this

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brief review article the authors explore the body of scientific literature that supports the use of a polarized model.

While there is still much work to do in this area, this review article identifies and discusses 7 research studies where the polarized model was either shown to be used by elite endurance athletes or experimentally compared with other training models to measure effectiveness in subjects ranging from recreational to elite performers. The article also does an excellent job of highlighting the need for quantifying training load using various tools such as heart rate, speed, power output and perceived exertion. The authors conclude their review with an example polarized training program to give some practical context to how this model may be used by a coach or athlete.

Future directions in this area include the need for more experimental studies designed to understand the mechanisms behind this training approach as well as potential effectiveness across a broader range of sports and physiological performance demands. ∆

www.sirc.ca

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.

Athlete Development A Skill Acquisition Perspective on Early Specialization in Sport. Anderson D, Mayo A. Kinesiology Review. August 2015;4(3):230-247.

Better Early Than Late? A Philosophical Exploration of Early Sport Specialization.

Torres C. Kinesiology Review. August 2015;4(3):304-316.

Developmental Trajectories in Early Sport Specialization: A Case for Early Sampling from a Physical Growth and Motor Development Perspective. Goodway J, Robinson L. Kinesiology Review. August 2015;4(3):267-278.

Early Sport Specialization from a Pedagogical Perspective. Hastie P. Kinesiology Review.

August 2015;4(3):292-303.

Analysis of the Elite Athletes’ Somatotypes. / Analiza Somatotipova Elitnih Sportaša.

Raković A, Savanović V, Stanković D, Pavlović R, Simeonov A, Petković E. Acta Kinesiologica. September 16, 2015;9:47-53.

Health and Nutrition Anti-inflammatory Dietary Interventions and Supplements to Improve Performance during Athletic Training. Buonocore D, Negro M, Arcelli E, Marzatico F. Journal Of The American College Of Nutrition.

September 2, 2015;34:62-67.

Coaches’ Knowledge and Management of Eating Disorders: A Randomized Controlled Trial. Martinsen M, Sherman R, Thompson R, Sundgot-Borgen J. Medicine & Science In Sports & Exercise. May 2015;47(5):10701078.

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Energy availability and the female athlete triad in elite endurance athletes. Melin A, Tornberg Å, Sjödin A, et al. Scandinavian Journal Of Medicine & Science In Sports.

October 2015;25(5):610-622.

Health in Elite Sports - a “Bio-PsychoSocial” Perspective. / Gesundheit im Spitzensport - eine „biopsychosoziale” Sichtweise. Thiel A, Schubring A, Schneider S, Zipfel S, Mayer J. Deutsche Zeitschrift Für Sportmedizin. September 2015;66(9):241-247.

Nutritional Supplement Habits of Athletes With an Impairment and Their Sources of Information. Graham-Paulson T, Perret C, Smith B, Crosland J, GooseyTolfrey V. International Journal Of Sport Nutrition & Exercise Metabolism. August 2015;25(4):387-395.

Coaching Coaches’ Perceptions of Team Cohesion in Paralympic Sports. Falcão W, Bloom G, Loughead T. Adapted Physical Activity Quarterly. July 2015;32(3):206-222.

Olympic Medal-Winning Leadership. Din C, Paskevich D, Gabriele T, Werthner P, Arnold R, Vella S. International Journal Of Sports Science & Coaching. September 2015;10(4):589-604.

Satisfaction with the Coach and Mental Toughness in Elite Male Ice Hockey Players.

Rodahl S, Giske R, Peters D, Hoigaard R. Journal Of Sport Behavior. December 2015;38(4):419-431.

Français

Psychology Comparing the Well-Being of Para and Olympic Sport Athletes: A Systematic Review. Macdougall H, O’Halloran P, Shields N, Sherry E. Adapted Physical Activity Quarterly. July 2015;32(3):256-276.

Examining Possible Relationships between Self-Determination and Burnout among Junior Athletes in Sport. Moen F, Federici R, Abrahamsen F. International Journal Of Coaching Science. July 2015;9(2):43-58.

Stressors, Coping, and Support Mechanisms for Student Athletes Combining Elite Sport and Tertiary Education: Implications for Practice. Cosh S, Tully P. Sport Psychologist.

June 2015;29(2):120-133.

Psychological Preparation for Paralympic Athletes: A Preliminary Study. Blumenstein B, Orbach I. Adapted Physical Activity Quarterly. July 2015;32(3):241-255.

General Conditioning Effects of Compression Garments on Performance and Recovery. Sakadjian A. Journal Of Australian Strength & Conditioning. June 2015;23(3):60-65.

Jump-Squat Performance and Its Relationship with Relative Training Intensity in High-Level Athletes. Jiménez-Reyes P, Pareja-Blanco F, Balsalobre-Fernández C, Cuadrado-Peñafiel V, Ortega-Becerra M, González-Badillo J. International Journal Of Sports Physiology & Performance.

November 2015;10(8):1036-1040. ‘’Live High--Train Low and High’’ Hypoxic Training Improves Team-Sport Performance.

Brocherie F, Millet G, Girard O, et al.

Medicine & Science In Sports & Exercise.

October 2015;47(10):2140-2149.

Maximal Aerobic Capacity in the WinterOlympics Endurance Disciplines: OlympicMedal Benchmarks for the Time Period 1990-2013. Tønnessen E, Haugen T, Hem E, Leirstein S, Seiler S. International Journal Of Sports Physiology & Performance.

October 2015;10(7):835-839.

HP SIRCuit Winter 2016

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Conference Calendar

For more events, check out the SIRC Conference Calendar

APRIL April 14-16

Research to Practice 2016

April 15-20

American Medical Society for Sports Medicine (AMSSM) 25th Annual Meeting International Conference on Sports Medicine and Fitness

April 18-20

July 6-9 July 6-9

MAY 17th European Society of Sport Traumatology and Knee Arthroscopy (ESSKA) Congress Canadian Academy of Sport & Exercise Medicine Annual Conference American College of Sports Medicineâ&#x20AC;&#x2122;s 63rd Annual Meeting 2016 JUNE North American Society for the Psychology of Sport and Physical Activity 2016 Conference 18th International Conference on Sports Science JULY European College of Sport Science Annual Congress National Strength and Conditioning Association

July 18-22

International Society of Biomechanics in Sport

May 4-7 May 18-21 May 31-June 4

June 15-18 June 20-21

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HP SIRCuit Winter 2016

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Melbourne, Australia Dallas, Texas Dubai, United Arab Emirates Barcelona, Spain Victoria, British Columbia Boston, Massachusetts Montreal, Quebec Paris, France Vienna, Austria New Orleans, Louisiana Tsukuba, Japan

www.sirc.ca

Pour plus d’information

For more information

sirc.ca/HPSIRCuit

www.sirc.ca

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sirc.ca/SIRCuitHP HP SIRCuit Winter 2016

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