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pulse Fall 2003 Vol. 16 No. 3

Message from the President Welcome on behalf of the executive committee, board of directors and staff of the Sport Medicine Council of Alberta. My term as the President of the SMCA has been an eventful one and one that has seen progress with many of the SMCA‚s goals and projects. I would like to thank our office staff who have been very effective at bringing about positive changes throughout 2003 and into the New Year. I would also like to thank the volunteers who helped make the casino fund raising event such a success in 2003 as this is one of our major fund raising efforts and contributes significantly to what we are able to achieve throughout the year. In addition, the SMCA would like to thank the ongoing support from our sponsors and membership. For being nominated and then subsequently traveling to Japan with the Alberta-Hokkaido sports exchange and Alberta Badminton, I would like to especially thank the board of directors. I represented the SMCA in September of 2003 to the Hokkaido Amateur Sports Science Association in Sapporo and greatly enjoyed the time spent there experiencing their culture and sport ˆ although not so much the earthquake! The coming months will see the introduc-

tion of many new resources for our library, the printing and publication of our revised Athletic First Aid manual, and the new Resource Directory. These items will complement the resources we already have to offer our members as well as the educational courses we offer. Please see our website for details at www.sportmedicinecouncilofalberta.ca <http://www.sportmedicinecouncilofalberta.ca/> or contact our staff for more information at (780) 415-0812. We look forward to continuing our efforts at sport safety promotion and injury prevention in Alberta and encourage members and the public to contact us with any questions or ideas. We also look forward to the ongoing relationship we have with our provider groups in Alberta ˆ the Alberta Society of Sport Medicine, Sport Physiotherapy Alberta, the Alberta Athletic Therapy Association, the Sport Science Association of Alberta, and the Sport Nutrition Specialists of Alberta. Finally, I would like to welcome new staff member Michelle Lyckman to our office who will sharing the position of Special Projects Coordinator with returning staff member Jana McCubbin. Best wishes in 2004 and play safe! Joel Weaver, MD, CCFP, CASM

Message from the SSAA

The past year was once again a productive one for sport science research in Alberta. The Sport Science Association of Alberta was involved with funding thirteen different research projects conducted by researchers from the Universities of Lethbridge, Calgary and Alberta. These projects spanned the research continuum of sport psychology, physiology, biomechanics, motor behavior/control and medicine. Alberta scientists seem to be on the cutting edge of sport science research. A good example of this is reported in this edition of Pulse and other examples can be found in the “publications” section of the Sports Medicine Council Alberta Web Site (www.sportmedicinecouncilofalberta.ca). These projects are good evidence for how such a granting program can bridge the gap between science and practice to benefit the research as well as sporting community. This work can have a direct impact on Alberta athletes and coaches. Currently, SSAA is working on the allocation of funds for the 2004 – 2005 research proposals and will look forward to new challenges and information by Alberta researchers in the upcoming year. Gordon J. Bell, Ph.D. Sport Science Association of Alberta

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The

Heart

Of the matter

Investigation of the effects of seven days of physical training on cardiac output and the subsequent heart rate vs. power output relationship. 4

SMCA Pulse Fall 2003


Cardiac Output From page 4 MJ. Black & SR. Norris Faculty of Kinesiology, Human Performance Laboratory, University of Calgary, Canada. Objective To investigate changes in the heart rate vs. power output relationship in response to seven days of intense physical training.

Design A quasi-experimental time series design with each subject acting as their own ‘control’ by utilizing a pre/during/post monitoring format.

Setting Study of local volunteers recruited via word-of-mouth and notice board ‘flyers’ from the competitive cycling community in Calgary, Alberta.

Participants Ten male volunteers participated in and completed this study (Age; 24.9±3.2 yr, Mass; 73.9±7.7 kg, ; 63.0±4.0 ml.kg-1.min1) were recruited. All 10 participants completed the study. All subjects were informed of the purposes of the study and associated risks as required by the Human Ethics Committee, Faculty of Kinesiology, at the University of Calgary.

Intervention Subjects performed a total of four incremental protocols (2 minute stages until ventilatory threshold, 1 minute stages from threshold to max). The first max test (7 days prior to training) was used to identify the pre-training , HRmax and maximal aerobic power, and to familiarize the subject with the protocol. On

the day prior to the training intervention, subjects reported to the laboratory in the morning for determination of plasma and blood volume. Two hours after this procedure the subjects performed a second with simultaneous cardiac output measurements. The following seven days consisted of 1.5 hours per day of high intensity training, with supplementary strength training sessions on the 2nd, 4th and 6th training days. One day post-training the subjects completed another plasma volume determination followed by the protocol with cardiac output measurements. All testing and training will take place at the Human Performance Lab, Faculty of Kinesiology, University of Calgary, Calgary, AB.

Main results Linear regression analysis of the HR vs. Power Output relationships across the duration of the investigation revealed statistically different slopes (‘flatter’) for days 3, 4, 6 and 7 as compared to the first training day (p<0.05). In contrast, no differences were found in the ‘intercept’ values (p>0.05). Maximum heart rates achieved were lower on training days 3 to 7 (greatest decrease on day 7) as compared to day 1 (p<0.05), although there were no differences if day 1 was excluded (p>0.05). Furthermore, there were no differences in the maximum power output attained or post-test blood lactates during these tests (p>0.05).

Conclusions These results suggest that short-term changes in stroke volume and, or, arterio-venous oxygen difference allowed the subjects to perform the incremental tests to the same peak performance values.

Source of Funding: Sport Science Association of Alberta (SSAA) through the ALBERTA SPORT, RECREATION, PARKS AND WILDLIFE

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All the

RAGE

The effect of situation criticality on the experience and expression of competitive anger across adaptive and maladaptive patterns of sport-perfectionism J.G.H. Dunn & J.K.H. Vallance Faculty of Physical Education & Recreation, University of Alberta, Edmonton Introduction Recent research in sport has suggested that the construct of perfectionism has both adaptive and maladaptive components

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(Dunn, Causgrove-Dunn, & Syrotuik, in press; Hall, Kerr, & Matthews, 1998). Results from these studies all suggest that certain aspects of perfectionism may adversely affect (or be related to) athletesâ&#x20AC;&#x2122; cognitions, affect, and behaviors in sport. Given the salient role that anger is believed to play in sport performance (Lazarus, 2000), identifying potential correlates and predictors

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Anger in sport From page 6 of the anger response in sport is an important research endeavor.

Objective This study had two major purposes: (1) to examine the influence of situation criticality on the experience and expression of competitive anger across adaptive and maladaptive profiles of perfectionism in competitive youth ice hockey, and (2) to examine the relationship between multidimensional perfectionism and trait anger in youth ice hockey.

Design

Correlational and Between-Group Differences.

Setting Local hockey arenas throughout the Edmonton region.

Participants Two hundred and thirty one competitive (Pee Wee Tier I, Bantam AA, AAA) male youth hockey players (M age = 14.16 years; SD = 1.03).

Measures/Instruments Players completed one self-report measure of perfectionism (MPS-Sport; Dunn et al., in press), two self-report measures of state anger (SAI; Spielberger, 1999), and one self-report measure of trait anger (TAI; Spielberger, 1999). Some of the original items on the anger measures were reworded to make them more relevant to the sport of hockey.

Main Results Dimensions of perfectionism that are generally considered to be maladaptive in nature (i.e., perceived parental pressure [PPP], perceived coach pressure [PCP], and concern over mistakes [COM]) were positively correlated with state and trait anger subscales which measured the likelihood of (a) feeling angry, (b) expressing anger verbally, and (c) ex-pressing anger at someone. These perfectionism dimensions (i.e., PPP, PCP, COM) were also positively correlated with predispositions to react with anger, and to harbor an angry temperament. In other words, players who scored higher on the maladaptive dimensions of perfectionism tended to experience and express anger more often than players with lower levels of maladaptive perfectionism. Results also suggest that maladaptive perfectionists are more likely to experience higher levels of anger following mistakes in competition than adaptive perfectionists. The only perfectionism subscale not related to anger was Personal Standards (PS). Two separate multiple regression analyses were conducted to examine if MPS-Sport subscales predicted trait anger. Both concern over mistakes and perceived coach pressure were significant predictors of angry temperament. Concern over mistakes was the only significant predictor of angry reaction. Cluster analysis was used to divide athletes into groups. One group was comprised of adaptive perfectionists (i.e., high PS scores and low PPP, PCP, and COM scores) and one group was comprised of maladaptive perfectionists (i.e., high scores on all four MPS-Sport subscales). A doubly multivariate repeated measures multivariate analysis of variance was then conducted to examine if adaptive and maladaptive perfectionists experienced different levels of anger as a function of making mistakes in high and low criticality situations. The high criticality situation described the player making a mistake late in the third period of tied game. The low criticality situation described the play-

er making the same mistake midway through the first period of tied game. Irrespective of whether mistakes were made in high or low criticality situations, maladaptive perfectionists reported significantly higher levels of anger (i.e., group main effect). Results also showed that irrespective of an athleteâ&#x20AC;&#x2122;s perfectionist orientations, athletes reported significantly higher levels of anger following mistakes in high criticality situations than in low criticality situations (i.e., situation main effect).

Conclusions These results strongly suggest that competitive youth hockey players with maladaptive perfectionist orientations are more prone to experiencing and expressing anger in hockey than their adaptive perfectionist counterparts.

Source of funding: Sport Science Association of Alberta through the Alberta Sport, Recreation, Parks and Wildlife Foundation. For more information contact: Dr. John Dunn, Faculty of PE & Rec, University of Alberta, Edmonton, T6G 2H9 (780) 492-2831.

Commentary To date, research on perfectionism in sport has examined youth athletes and amateur adult athletes. Several prominent sport psychologists have postulated that it is the adaptive perfectionist orientation that is believed to be characteristic of highlevel performance. An investigation examining elite level athletes and their perfectionist orientations would facilitate a deeper conceptual understanding of adaptive perfectionism in sport. It would also be prudent to explore the impact of developing and using practical techniques that would help athletes to (a) set high (but achievable) personal standards and performance goals, (b) avoid the destructive tendency of being overly critical about personal performance, and (c) view performance mistakes as learning opportunities for skill development. Finally coaches and parents should be aware that the type of standards that they set for young athletes, and the type of feedback (and rewards) that they provide for athletes following their performance attempts might influence the degree to which athletes develop adaptive or maladaptive perfectionist tendencies.

Practical Implications We recommend that parents and coaches should encourage their athletes or children to strive for perfection in sport. However, we caution coaches and parents about the dangers of demanding perfection. Such demands (and the standards that go with them) are generally unattainable. Such an environment will create undue pressure on young performers, who will ultimately become frustrated with their lack of success (i.e., because perfection is rarely if ever achieved). Continual frustration caused by a perceived lack of success can lead to excessive levels of anxiety and anger, which can ultimately lead to a general sense of failure and may contribute to early burnout or dropout from the sport environment.

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Training

and the immune system

The effect of off-season training programming for Edmonton rowers and its effect on immune system function.

G. Bell, C. Sellar, D. Syrotuik, C. Field Faculty of Physical Education and Recreation and Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Alberta, Canada. Introduction Intense, prolonged exercise is known to influence the ability of the immune system to function properly after exercise (Mackinnon, 1999, Advances In Exercise Immunology). Nieman (2000, MSSE, 32(7): S406-S411) has suggested that this

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period of altered immune function may provide an â&#x20AC;&#x153;open-windowâ&#x20AC;? for an infection to take hold in the body. As with other full-body intense exercise, rowing exercise has been shown to cause an alteration in certain aspects of the immune system (Shephard, 1998, J. Sport Sci.,16: 603-620) and has been linked to higher levels of stress hormones compared to other forms of exercise (Secher, 1993, Sports Med., 15(1): 24-42.). This may be part of the reason why the immune system may not function properly after exercise (Gleeson and Bishop, 2000 Immun. & Cell Bio., 78: 554-561; Castel et al. Eur. J. App. Physiol., 73:

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Rowing From page 8 488-490). Carbohydrate supplementation before, during, and after exercise has been proposed as a means of reducing the negative effects of exercise on immune function following exercise (Nieman and Pedersen, 2002, Nutrition and Exercise Immunology). It has been suggested that carbohydrate supplementation will reduce the release of certain stress hormones during exercise and provide adequate fuel for immune cell functioning (Gleeson and Bishop, 2000 Immun.& Cell Bio., 78: 554561). It was hypothesized in this study, that carbohydrate supplementation during prolonged rowing exercise would reduce the negative effects of exercise on the immune system and stress hormone production.

Objective The purposes of this study were to determine the effect of 1hour of rowing exercise and carbohydrate supplementation on the immune and hormonal response following exercise.

Design Quasi-experimental design.

Setting University of Alberta, Edmonton.

Subjects The subjects (n = 22) were a combination of on-water and indoor-only rowers from the local rowing community.

Intervention/Main Outcome Measures Each subject completed a 10 week combined strength and endurance, off-season training program. Following training, all subjects completed a 2000-metre simulated rowing race and was then matched on time and randomly assigned to a carbohydrate or placebo group. A 3-day dietary record was obtained and used to alter the intake of all subjects so that they consumed 55% carbohydrate for the three days leading up to a 1-hour row. Next, the subjects were provided with a standardized pre-event meal and completed a 1-hour row for maximum distance during which time they ingested either a carbohydrate or placebo beverage at regular intervals before, during, and after their 1-hour row. Blood was taken from the subjects at rest before and after 5 and 60 minutes of rowing. All samples were analyzed for blood glucose, stress hormones, and various immune measures. All subjects also completed a combined maximal oxygen consumption/ ventilatory threshold test (VO2max/VT test), to determine the relative intensity that the subjects maintained during their 1hour row. All subjects were required to report any illness for a 14-day period following the 1-hour row.

cise. Also, the concentrations of adrenocorticotropic hormone and cortisol were significantly elevated immediately following exercise in both groups, which paralleled the changes seen in the immune parameters. Carbohydrate supplementation during the 1-hour row showed significantly higher blood glucose levels compared to placebo. There was a significantly higher level of circulating lymphocytes immediately after exercise in the placebo group indicating that supplementation of carbohydrate was able to reduce the elevation of these cells, post exercise. There were no other differences observed between the carbohydrate supplementation group and the placebo group. Also, there was no difference in the incidence of illness between the carbohydrate and placebo groups in the 14 days following the 1-hour row.

Conclusions One hour of rowing exercise was sufficient to influence the function of the immune system and carbohydrate supplementation maintained blood glucose levels and reduced the release of lymphocytes after exercise. It seems that ingestion of carbohydrate was unable to show any further effects on the immune system or hormone release with rowing exercise of this duration and intensity. Furthermore, there was no significant increase in the incidence of illness reported by the subjects for a two-week period following the 1- hour row. Thus, although carbohydrate ingestion during intense long duration exercise is necessary for metabolic reasons (e.g. maintenance of blood glucose), the effect of reducing the negative influence of exercise on the immune system was minimal in the present study.

Source of funding: Sport Science Association of Alberta (SSAA) through the Alberta Sport, Recreation, Parks and Wildlife Foundation.

For more information contact: Dr. Gordon Bell, Faculty of Physical Education and Recreation, E424 Van Vliet Center, University of Alberta, Edmonton, AB, T6G 2H9.

Commentary Completion of a long duration rowing exercise bout similar that performed during a typical off-season training session showed that this type of exercise can reduce some aspects of immune cell functioning following exercise. While a single bout of rowing exercise did not increase the incidence of illness in our subjects, there still may be an increased risk following repeated training bouts. Supplementation with carbohydrate was shown to have some effect on the post exercise immune response to one hour of rowing exercise but this effect was minimal. However, it is important to maintain proper nutrition during periods of training in order to maintain metabolic energy supply, hormone response and immune function.

Main Results The subjects rowed at an average of 72% of VO2max for the 1-hour bout (estimated using power output from 1-hour row compared to power output values from the VO2max/VT test). There were no significant differences in performance between the carbohydrate and placebo group for the 1-hour row. There were significant alterations in a number of immune cell measures. The circulating levels of leukocytes (white blood cells), neutrophils, lymphocytes, and natural killer cell activity were all significantly altered following exercise when compared to resting values. All of these changes indicate that the immune response was negatively influenced by 1-hour of rowing exerSMCA Pulse Fall 2003

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Doing

Handsprings

Assessment of current practices in technique development for the back handspring in gymnastics P. Gervais, J. Steven LeBlanc, Derek Kivi, M. Moreau and Brian Maraj Sports Biomechanics Lab, Faculty of Physical Education and Recreation.University of Alberta, Introduction In tumbling the back handspring is most often used as a transitional skill in combination with a lead in skill such as a roundoff into a backward directed skill such as backward somersault. 10 SMCA Pulse Fall 2003

The back handspring is first introduced to gymnast at a young age and is a skill that is very frequently executed in training and competition through out a gymnastâ&#x20AC;&#x2122;s career. Koh et. al. (1992) and Hall (1982) have suggested that the repetitive loading about the upper extremities and the extreme range of motions seen in the lumbar spine in back handspring may put the gymnast at risk of overuse injuries. They also suggest that this risk can be increase due to poor execution often observed during the early phases of learning. Gymnastics Canada maintains that a major

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Gymnastics From page 10 role of coaching tumbling is the use of training ‘gimmicks’ which permit the safe learning of tumbling skills especially during the critical early stages of development (Kinsman, et. al., 1986).

Objective It was the purpose of this study to examine four different back handsprings used for teaching and training the back handspring in artistic gymnastics.

Design Repeated measures, quasi-experimental research design.

Setting Sports Biomechanics Lab, University of Alberta, Alberta.

Subjects Four young male gymnasts (10, 11, 2@12yrs) were recruited. These gymnasts were class 4 national stream competitors. Parental consent was acquired for the study. The boys were all familiar with all 4 variations of the back handspring.

Intervention/Main Outcome Measures The gymnasts were fitted with reflective markers over the joint centers on the side of the body closest to the cameras. Data was collected using standard 2D video techniques using two JVC GR-DVL9800 cameras operating at 120Hz. Video data reduction and analysis was performed using the APAS system by Ariel Dynamics Inc. The gymnasts tumbled on a standard tumbling mat 5cm in thickness. An AMTI model OR6-3 force plate was mounted under the mat and was used to measure force during hand contact. Force data was collected at 1200Hz. Synchronization between video data and force measures was achieved using an externally triggered LED visible to the cameras and monitored on an additional A/D channel. The four trial conditions consisted of 1) a spotted standing back handspring, 2) a standing back handspring performed down an inclined mat, 3) a back handspring preceded by a round-off and 4) an “accelerated” back handspring. The incline mat is a common learning tool used in gymnast instruction. This mat had a 2m base and height of 46cm providing a slope of 13 degrees. For the 2nd condition the gymnasts started with their feet on the inclined mat and had the hands making contact with the level tumbling mat over the force plate. For the last condition, the accelerated back handspring, the round-off was initiated on the incline with the feet landing on the tumbling mat proceeding into the back handspring. A one-way ANOVA with repeated measured was used for statistical analysis. The p-level was set at 0.05. A LSD post-hoc test was used where warranted.

Figure 1: Peak vertical ground reaction forces on the hands. two back handsprings utilizing the inclined mat and the roundoff back handsprings produced greater linear momentum in the direction of progression than the assisted back handsprings. Contact time on the hands was found to be significantly higher for the standing back handsprings (1 & 2) when compared to conditions 3 and 4, which included a round-off. Kinematic descriptors related to body position at foot and hand contact did not appear to be significantly different across conditions however, based on the angle of incidence at hand contact, the inclined back handspring had gymnasts landing in a more vertical position.

Conclusions The back handspring performed down the inclined mat appears to provide the learner with the best translational characteristics of the four back handsprings tested. There is little evidence to suggest that any one of these back handsprings put the young gymnast at a greater risk than another.

Source of funding: Sport Science Association of Alberta (SSAA) through the Alberta Sport, Recreation, Parks and Wildlife Foundation.

For more information contact: Pierre Gervais, Ph.D. at: Faculty of Physical Education and Recreation, University of Alberta, Edmonton, AB, T6G 2H9.

Commentary The back handspring is a critical fundamental skill in artistic gymnasts that must be mastered at a young age but in a safe and effective manner. The back handspring taught with the use of an inclined mat appears to provide a safe and effective means for young athletes to get the ‘feel’ for and practice the back handspring.

Main Results Peak vertical ground reaction forces were found to be significantly lower in the spotted standing back handsprings than in the other three back handspring conditions (p<0.01). There were no significant differences in vertical forces between the other three back handspring conditions. These relationships are illustrated in Figure 1. The mean for the 4 gymnasts under the four conditions for vertical force was 3.57BW (SD=0.80BW). Although approaching only conventional levels of significance, the

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Elbow Grease

Effectiveness of Extracorporeal Shockwave Therapy in the Treatment of Untreated Lateral Epicondylitis B. Chung and J. P. Wiley Faculty of Kinesiology, University of Calgary Introduction LE is commonly observed in the athletic population, especially in sports such as tennis and other racquet sports as well as golf, bowling, martial arts and some paddle sports. The prevalence of LE amongst amateur tennis players has been estimated to be 50% (Geoffroy et al, 1994). In golf, 27% of players suffer from LE. Several studies have examined the effect of low-energy extracorporeal shockwave therapy (ESWT) on LE (Gigliotti et al., 1999, Haist, 1999,

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Tennis elbow From page12 Kriskchek et al., 1999, Rompe et al., 1996). These studies have focussed on patients who have failed non-operative treatments. Success rates reported in the literature for ESWT in LE range from 60 to 85%. This consistent result has yet to be demonstrated in any other modality of treatment for LE, including ultrasound therapy, ionisation, non-steroid anti-inflammatory drug (NSAID) therapy, steroid injection, and manipulation (Labelle et al. 1992). There have been no studies to date that have investigated ESWT as a primary treatment for LEâ&#x20AC;&#x201D;that is before physical therapy and/or corticosteroid injection.

Objective: The aim of this study is to determine whether ESWT is effective as a primary therapy for individuals who suffer from LE.

Design

jects in the sham group and 1 subjects in the active group were lost to follow-up. In the sham group, 9 subjects were classified as treatment successes and 20 subjects as treatment failures. In the active group, 12 subjects were classified as treatment successes, and 19 subjects as treatment failures. No significant difference in treatment success/failure was detected (_2=0.3880, df=1, p=0.533) between active and sham groups. Scores are provided in table 1.

Randomized control trial.

Setting Sport Medicine Centre, Faculty of Kinesiology, University of Calgary, AB.

Subjects The sample population consisted of 60 consenting skeletally mature individuals (defined as 18 years of age and older) with a confirmed diagnosis of LE by the study physician, who had not yet received treatment for their LE, who were either referred to this study by their family physician or who volunteered to participate in this study and who were not contraindicated to receive ESWT. Elite level athletes and Workerâ&#x20AC;&#x2122;s Compensation Board claimants were excluded from the study. All subjects signed a consent form. This project was approved by a University of Calgary Research Ethics Board.

Intervention/Main Outcome Measures

Conclusions Despite the improvement in pain scores and pain-free maximum grip strength within groups, there does not appear to be a difference between treating previously untreated LE with ESWT with a simple forearm stretching program or with a simple forearm stretching program alone with respect to resolving pain symptoms within an 8 week period. This cohort is still being followed for the remainder of their full follow-up period of one year to address secondary outcomes and study objectives

Source of Funding: Sport Science Association of Alberta (SSAA) through the Alberta Sport, Recreation, Parks and Wildlife Foundation.

For more information contact Dr. J. Preston Wiley, phone: (403)220-8518 Email: wiley@ucalgary.ca

Subjects were randomly allocated (Random permuted block randomization, envelop concealment) to receive 3 weekly sessions of real (total energy flux density range 0.03-0.17mJ/mm2) or sham ESWT. All subjects were taught a home forearm extensor stretch. Subjects were followed for 8 weeks post-inclusion and were assessed for over all pain (Visual Analog Scale (VAS)), quality of life (EuroQol questionnaire), and maximum pain-free grip strength. The primary outcome for this study was treatment success/failure based on fulfilling all of the following criteria: 1) at least a 50% reduction in the overall pain VAS; 2) a maximum allowable overall pain VAS score of 4.0cm; and 3) no use of pain medication for elbow pain between week 6 and week 8. An intention to treat analysis was performed on the primary outcome using the last-observation-carried-forward approach for missing values. Confidence intervals for VAS scores, quality of life and maximum pain-free grip strength, by treatment group, were calculated.

Main Results Subjects were recruited between February 2002 and September 2002. 29 subjects were randomly allocated to the sham ESWT group, and 31 subjects were randomly allocated to the active ESWT group. 4 subSMCA Pulse Fall 2003

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Water power

Water immersion and breath holding with or without cycling and arm cranking exercise in a hydrostatic tank

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Water Immersion From page 13 T. Alentejano and D. Marshall. Faculty of Physical Education and Recreation, University of Alberta, Alberta, Canada. Introduction Synchronized swimming (Synchro) is one of the only sports where the athlete performs high intensity exercise while holding their breath for various periods of time underwater. This may lead to a lack of oxygen delivery (hypoxia) to the working tissues and brain and produce a build up of carbon dioxide (hypercapnia) among other physiological consequences (Davies et al., 1995). Many of these physiological consequences as a result of breath holding during exercise have been assumed from other types of investigations of exercise not specifically performed under water in a sport specific manner. It is not uncommon to hear anecdotal reports of loss of consciousness during Synchro practices or competitions, where athletes have held their breath for an inappropriately long time period.

Objective This study examined the physiological effects of breath holding (BH) during exercise while immersed in water in synchronized swimmers and recreational swimmers.

Design Two group comparison.

Setting University of Alberta, Edmonton.

Subjects The subjects were a group of synchronized swimmers (n=15) aged 17.7 ± 2.2 years and a group of recreational swimmers aged 22.0 ± 2.7 (mean;SD). The subjects were volunteers and signed an informed consent form that was approved by the Faculty of Physical Education and Recreation research ethics committee. All subjects were required to be able to hold their breath for at least 45 seconds out of the water. The two groups were matched for sitting height in an attempt to control for differences in lung volumes and required to have a ratio of forced vital capacity in one second to total forced vital capacity of at least 75%.

minutes rest in between each trial, was performed by each subject. After adequate recovery, an arm cranking ventilatory threshold/ VO2 peak exercise test was performed. The second testing session (3 to 5 days later) consisted of performing 6 breath holds (10, 20 and 25 s repeated twice) interspersed by two minute active recovery periods during arm cranking exercise performed underwater at an intensity set below ventilatory threshold. For all exercise testing, subjects were monitored using a breath by breath metabolic measurement system (MedGraphics CPXD). A modified mouthpiece and two way hose system was used to collect the expired air. Heart rate was measured using a telemetric heart rate monitor (Polar), and pulse oximetry was measured.

Main Results There were no statistical differences in height, sitting height and weight between groups, although the synchronized swimmers were significantly younger than the controls. During the 5 breath holding trials, breath holding times in both groups increased from Trial 1 to Trial 5 (SS= 71 – 109s; controls=57 – 78s). With the exception of the first breath holding trial, where there were no differences between the groups, the swimmers held their breath significantly longer than the controls in trials 2-5. Analyses of other physiological parameters such as HR and O2 saturation during breath holding, and oxygen consumption and saturation before and after breath holding, are ongoing.

Conclusions We anticipate that results will show a physiological adaptation in synchronized swimmers that allows for prolonged breath holding during underwater performance. Further, we anticipate providing synchronized coaches with specific recommendations around training and choreography.

Source of funding: Sport Science Association of Alberta (SSAA) through the Alberta Sport, Recreation, Parks and Wildlife Foundation.

For more information contact: Dru Marshall, Ph.D. or Teresa Alentejano, Ph.D. candidate, Faculty of Physical Education and Recreation, E424 Van Vliet Center, University of Alberta, Edmonton, AB, T6G 2H9.

Intervention/Main Outcome Measures Each subject was familiarized with all procedures prior to data collection. Anthropometric (height, body mass, sitting height), lung capacity and other descriptive data were collected on each subject. An underwater combined arm and leg ergometer was custom designed for this study based on Chen et al. (1996). This device was positioned in a tank designed for hydrostatic weighing that allowed subjects to exercise under controlled work rates while under water. Subjects were immersed to the clavicular notch for all testing and wore a weighted belt to ensure they remain submerged. Water temperature was kept constant at 28 degrees C. A certified lifeguard was present for all testing. During the first testing session, a series of 5 trials of maximum breath holding (without exercise), with an interval of 2

E-mail: zaki196@home.com

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Objective The purpose of this project was to develop a convenient method for athletes to estimate the energetic cost of individual running workouts.

Design Quasi-experimental design.

Running on empty

Setting University of Alberta, Edmonton.

Subjects Male and female subjects (between the ages of 24-53 years) were healthy, active and accustomed to running as a mode of training.

Field versus laboratory assessment Intervention/Main Outcome of energy expenditure in runners. Measures

Informed consent was obtained from all subjects. The following tests were then completed:

VJ Harber, W Rodgers, G Bell, K Courneya Faculty of Physical Education and Recreation, University of Alberta

Test Day 1: 1. PAR-Q 2. Height and weight 3. Anaerobic threshold (AT) determination (Rhodes and McKenzie, 1984) using a metabolic cart system (MedGraphics). Test Day 2: 1. 2-4 days following the AT test, subjects completed 3 - 10 minute bouts of exercise on a treadmill (Low = 50 - 55%, Medium = 65-70% and High = 85-90% of AT) separated by a 5 minute rest interval. A Digiwalker pedometer was worn for each 10-minute bout to measure the number of steps taken for each workload. As well, HR, RER, O2 consumption and CO2 output was monitored for each workload. The caloric cost

Introduction Energy requirements for each athlete are unique. Physical exercise by means of training or competition will increase daily energy expenditure by 480-960 kcal/hr, depending on individual fitness, duration, type and intensity of the sport (Burke 2001). As a result, athletes are challenged to increase food consumption to meet their energy needs. Some athletes face numerous obstacles in providing their bodies with adequate nutritional support. A problem faced by many athletes include the timing of meals around multiple daily training bouts. As well, higher intensity exercise reduces appetite, digestion and absorption and often leads to infrequent or smaller volume meals (Burke 2001). Less-than-adequate energy (macronutrient and micronutrient) intake is identified as a risk factor for overtraining. Impaired recovery, poor rate of skeletal muscle repletion, reduced opportunity to manipulate muscle mass and body fat level, decline in hormonal and immune function are associated with insufficient energy intake (Burke 2001). Optimal function and health are also compromised. The Digiwalker is an accurate, electronic pedometer that monitors the number of steps when worn on a belt or waistband. Stride length can be established for each person at varying speeds (eg. walking, jogging, running). Total distance can be determined as a result. Estimates of energy expenditure, although available on some Digiwalker models, use a fixed formula of 0.55 kcal/kg body weight/step. This formula may be appropriate for general walking speeds but would not be accurate for varying speeds of running (Bassett 2000).

(kcal/min/kg; Weir equation) of each intensity was calculated. 2. Subjects repeated the 3 â&#x20AC;&#x201C; 10 minute bouts of exercise (5 min rest intervals) on an indoor track wearing the HR monitor and pedometer. Subjects were instructed to maintain the same HR (+ 5 bpm) obtained during the treadmill runs at the different workloads. HR (each minute) and total steps accumulated were recorded.

Continued on page 17

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Energy expenditure From page16 Conclusions Using a pedometer combined with HR, is an effective tool for monitoring energy expenditure during running at low, medium and high intensities.

Source of funding: Sport Science Association of Alberta (SSAA) through the Alberta Sport, Recreation, Parks and Wildlife Foundation.

For more information contact: Dr. Vicki Harber, Faculty of Physical Education and Recreation, E424 Van Vliet Center, University of Alberta, Edmonton, AB, T6G 2H9.

Commentary

different running intensities for individuals accustomed to running activity. This easy-to-use and convenient tool for use in the field may help provide individualized, specific strategies for energy compensation. Establishing energy balance in active individuals will help maintain a strong training profile and likely prevent some of the negative metabolic adaptations known to occur with inadequate energy intake.

The Digiwalker pedometer can estimate the energy cost of

Sport Factor

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For the

FUN of it

Youth soccer players’ experience of enjoyment

Jochen Bocksnick Department of Kinesiology, University of Lethbridge Introduction Contemporary research documents significant dropout rates from organized youth sports and associates the declining numbers with lack of fun/enjoyment and negative self-evaluations on the part of the athletes. The traditional delivery of sport games like soccer and hockey has relied heavily on playing the game in competitive environments while neglecting the development of individual skills. The rationale for this approach has centered on the belief that children will be attracted to “playing” the game rather than “working on” the skills. Unfortunately, this ideology neglects that teaching of rudimentary sport-specific skills can be accomplished through “playful” teaching situations. It is hypothesized that the participating children will respond rather favorably regarding their experiences of fun/enjoyment because of a higher frequency of personal success experiences as a result of the instructional setting. These success experiences can be attributed to a greater opportunity in handling and manipulating the ball. Related research has shown that the average hockey player will experience far less than a minute of puck handling-contact during a competitive game, but infinitely more contact time during practice situations. Assuming that individual drills will be presented in such a way that children can master the objectives of the tasks, it is anticipated that this will result in positive affect and enjoyment.

Objective The primary focus of this study is to determine whether or not the participating youth players will perceive the structured instructional setting with its equal time allotment for practicing individual techniques and soccer-specific small-group games enjoyable.

Design

grades one through four. Sixty-two out of 84 participants returned complete questionnaire sets. A questionnaire set referred to a completed form by both youth participant and at least one parent/legal guardian.

Intervention / Main Outcome Measures This study is concerned with the enjoyment youth soccer players experience while participating in a sport-specific instructional program. A Skills Approach for Learning and Teaching Soccer (SALTS) resulted in the design of a unique instructional program in which participants receive an equal amount of practicing time for individual and smallgroup tactics-related soccer skills and playing time. The children were instructed in groups of ten, twice a week for sixty minutes each session, for ten weeks between late April and June. The children were grouped into two consecutive instructional sessions of Grade 1 and 2 students and Grades 3 and 4 students, to facilitate an age-adequate teaching environment. At program end, participants received a self-addressed and stamped questionnaire that was to be completed by both youth participant and at least one parent independent of each other. Returning the questionnaire, for which no name identification was required, was considered as consenting to participation in the study.

Main Results No significant differences were found when comparing the responses of boys and girls; both groups expressed great enjoyment as a result of their participation in the program. Using a repeated measures analysis of variance to contrast responses of children with their corresponding parents showed that children reported significantly greater enjoyment than their parents who were asked to gauge their children’s program-related affect. Interestingly, for data sets that were comprised of child, mother and father, the results suggested that fathers reported significantly lower than both other respondents.

Conclusion The triangulation of the information revealed important differences and suggests considering the respondent groups separately. Most importantly it is necessary to consider the voices of youth participants.

One-sample program evaluation.

Setting Sport fields at the University of Lethbridge, Lethbridge, Alberta.

Subjects Subjects for this study were recruited from the SALTS-program (i.e., Skills Approach for Learning and Teaching Soccer) on a volunteer basis. The subject pool consisted of boys and girls currently enrolled in

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Source of Funding Sport Science Association of Alberta (SSAA) through the Alberta Sport, Recreation, Parks and Wildlife Foundation.

For more information contact Dr. Jochen Bocksnick, phone: 403 329-5188 e- mail: bocksnick@uleth.ca


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Pulse Magazine Fall 2003  

The Magazine of the Sport Medicine Council of Alberta

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