Fall 2008

The Magazine of the Sport Medicine Council of Alberta

Fall 2008 Edition

The Magazine of the Sport Medicine Council of Alberta

Sport Science Issue

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table of contents

2 SMCA Pulse Fall 2008

pulse

Fall 2008 Vol. 21 No. 3 SMCA Board of Directors President Dwayne Laing BPE, CAT (c) Vice-President Ray Kardas Secretary Gabrielle Cave BSc, P.T., MCPA Treasurer Michael Becher SNS Rep Steve Johnson SPC Rep Chris Holt AATA Rep Breda Lau BPE, CAT (c) SSAA Rep Stephane Simard MSc Member at Large Kristine Godziuk SMCA Employees Executive Director Vacant Accounts Manager Janice Peters, BCom Technical Director Nicole Lemke, BPE, Adv. Cert. AT, CAT (c) Pulse Magazine Published by: Sport Medicine Council of Alberta 11759—Groat Road Edmonton, Alberta, Canada T5M 3K6 Phone: (780) 415—0812 Fax: (780) 422-3093 Website: www.sportmedab.ca Email: [email protected]

Contents copyright 2008 by SMCA. Articles may not be reprinted without permission. The opinions are those of the respective authors and are not necessarily those of the SMCA. ISSN: 1181-9812 Publication agreement no. 40038086

Latest News from the SMCA…………………….Page 3 Upcoming Courses………………………….…….Page 3

A Comparison of Two Different Rowing Techniques on Energy Expenditures and Power Output Pages: 4-5

Can Health and Fitness Parameters Be Improved In Masters Athletes with a 10 Month Training and Nutrition Program Pages: 6-7 Pacing Strategy for 1500M Speed Skating Pages: 8-9

A Re-Examination of the Relationship Between Sport-Based Perfectionism and Achievement Goal Orientations Among Youth Ice Hockey Players Pages: 10-11

Leptin and Insulin Response to Varying Energy Availability in Women Pages: 12-13 The Effect of Reduced Carbohydrate Diet on Ammonia-Lactate Ratio at 102% of MLSS Pages: 14-15

State of the Student Athlete: Evaluation of Pre-Season Fitness Pages: 16-17

Release Characteristics of the Long Swing Hang Uprise, Moy and Back Giant Swing on Parallel Bars in Men’s Artistic Gymnastics Pages: 18-19

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Latest News from the SMCA

The Sport Medicine Council Of Alberta Would Like To Thank Our Partners For

Their Support 3 SMCA Pulse Fall 2008

Season’s Greetings from the SMCA Merry Christmas from the SMCA staff! Have a safe and festive holiday season. Sport Concussion Course Launch On November 22, 2008 the SMCA launched their new Sport Concussion course. Dr. Martin Mrazik and his graduate student, Andrea Krol, conducted the presentation. A discussion period followed. Participants with varying backgrounds voiced many important ques-tions. With new research coming out all the time, this course will continue to grow. Thank you to everyone who attended this presentation. The feedback was very positive, and we look forward to offering this course in 2009. Thank you also to everyone who provided a donation to the Northern Alberta Brain Injury Society (NABIS). Resource Directory Update The SMCA is looking to update their online Resource Directory. This directory assists people in locating sport medicine professionals throughout Alberta. If you are already in our directory, please view your contact infor-mation and make sure it is current. Visit http://www.sportmedab.ca/directory.php to view our online directory. We are always looking to add new professionals. Contact us at [email protected] if you would like to be added. New Rental Kits The SMCA has purchased and stocked 10 new Therapist and 8 new Physician rental kits. This expansion to our rental kit inventory was made possible through support from the Community Development Initiatives program and the Alberta Lottery Fund. Both kits are a semi-rigid construction with Velcro dividers to keep contents or-ganized. These new kits are available for purchase or create a custom order, and we will build the bag to your specifications. For more information visit www.sportmedab.ca or contact 780-415-0812.

Offer valid until May 15, 2007. To order, please visit www.sportmedab.ca or call (780) 415-0812.

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Sport Nutrition Level 1 January 17, 2009 January 31, 2009 Location: Whitecourt Location: Calgary Host: Town of Whitecourt Host: Preventous Collaborative 10:00—16:00 Health 780-778-3637 10:00—16:00 403-229-0129 February 7, 2009 Location: Edmonton Host: SMCA 10:00—16:00 780-415-0812

Athletic First Aid January 17 & 18, 2009 January 24, 2009 Location: Grande Prairie Location: Edmonton Host: ASDC NW Host: SMCA 12:30—16:30 & 08:30—12:30 08:30—16:30 780-539-2816 780-415-0812 January 31, 2009 Location: Calgary Host: SMCA 08:30—16:30 780-415-0812

Taping & Strapping January 25, 2009 February 1, 2009 Location: Edmonton Location: Calgary Host: SMCA Host: SMCA 08:30—16:30 08:30—16:30 780-415-0812 780-415-0812

Sport Trainer Combination of Athletic First Aid and Taping & Strapping

January 24 & 25, 2009 Jan. 31 & Feb. 1, 2009 Location: Edmonton Location: Calgary 780-415-0812 780-415-0812 08:30—16:30 08:30—16:30

FOR MORE INFORMATION VISIT WWW.SPORTMEDAB.CA OR CALL 780-415-0812

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A Comparison of Two Different Rowing Techniques on Energy Expenditure and Power Output G. Bell, D. Syrotuik, B. Reynolds & J. Bennet Assistant Professor Faculty of Physical Education and Recreation University of Alberta Edmonton, Alberta Introduction The transfer of force to the oar of a rowing racing shell or handle of a rowing machine requires timing and proper kinematics such that at the start of the stroke (catch), the knee, hip, trunk and arm angle are in an opti-mal position followed by a coordinated sequencing of hip, leg and arm movements all contributing to the de-velopment of power during the drive phase through to the completion (finish) of the stroke (Bompa, 1980; Hartman et al., 1994; Martindale and Robertson, 1984; Torres-Moreno et al., 1999). Currently, a modified row-ing stroke has emerged that involves a more extending upper body position at the finish of the stroke (i.e. greater hip angle in comparison to the more traditional

less extended finish). It has garnered some controversy among the rowing community as it has been stated, an-ecdotally, that this extended finish rowing technique is more energy demanding at the same time as producing greater power output. Thus, “cost-benefit” of this tech-nique may be an issue, however, there is no research to document this. Objective The purpose of this study is to compare the metabolic responses to rowing exercise using the traditional tech-nique versus the modified extended technique in rowers. It is hypothesized that the modified extension technique would provide greater power output and be more en-ergy demanding at the same rowing stroke rate but not at the same power output. Design Quasi-experimental design. Setting University of Alberta, Edmonton. Subjects Competitive, club level male and female rowers volun-teered to participate in this investigation. This study was approved by a University Research Ethics Board.


Intervention/Main Outcome Measures The exercise testing involved two visits to the exercise physiology lab: one session for peak oxygen consump-tion (VO2peak) testing and a second for the experimen-tal exercise trials. The experimental session required 3 graded exercise tests that include 3 different intensities in random order: Trial 1: Traditional technique @ 125, 150 & 175 at an 18, 22 and 26 stroke rate (SR). Trial 2: Modified technique @ 125, 150 & 175 at a vary-ing SR. Trial 3: Modified technique @ 18, 22 and 26 stroke rate (SR) at a varying PO. The traditional technique requires an upper body exten-sion of 105 degrees about the hip at the finish whereas the modified extension technique requires an extension of 150 degrees as determined with a goniometer. A structure was fabricated that controlled the extent of the lay-back position of each rower at the experimental hip angles. Verbal feedback was also provided by a re-searcher for all subjects in aid of controlling the proper technique during testing. Main Results The subjects were a combination of light and heavy weight men and women. The mean (± SD) age, height, body mass and VO2peak was 26.5 ± 6.9 years, 186.3 ± 13.4 cm, 85.4 ± 16.4 kg and 50.5 ± 7.62 ml/kg/min for men and 25.3 ± 4..5 years, 171.3 ± 9.3 cm, 72.4 ± 6.8 and 44.8 ± 6.4 ml/kg/min for women, respectively. At the same stroke rate, PO was 25, 23 and 28% higher at 125, 150 and 175 watts when using the modified tech-nique and was associated with 17, 13 and 17% greater energy expenditure (kcal/min), respectively. When the three submaximal PO’s were matched, the modified

technique resulted in 2, 3 and 3 fewer strokes per min-ute at 125, 150 and 175 watts, respectively in compari-son to the traditional technique but with similar energy expenditure. Conclusions These observations support our hypothesis and suggest that a greater “lean back” at the finish of the rowing stroke will produce greater power output than the tradi-tional more upright position. However, this technique is also more energy demanding and may result in greater fatigue. As well, when power output is matched be-tween the two different techniques, stroke rate is lower when using the modified greater “lean back” technique but energy expenditure remains the same. Source of funding: Sport Science Association of Alberta (SSAA) through the ASRPWF. For more information contact: Dr. Gordon Bell, Faculty of Physical Education and Rec-reation, E488 Van Vliet Center, University of Alberta, Edmonton, AB, T6G 2H9. Commentary The sport of rowing is highly competitive at the provin-cial, national and international level and Canadian rowing has been at the forefront for many years. This is true for the more traditional on-water sport but also for on-land rowing competitions (e.g. C.R.A.S.H.-B. Sprints Indoor Rowing Championships). Regardless of the rowing fo-rum, subtle changes in technique can often lead to posi-tive changes in performance. This is true for both on-water and off-water (rowing machine) performance row-ing. The degree to which a rower extends about the hip when rowing can influence the amount time there is

force applied to handle at the same stroke rate. Our research has shown that at the same stroke rate, there is an increase in power output at the same stroke rate but this is associated with a greater metabolic energy demand. When power output is controlled, there is little difference between metabolic energy expenditure using the tra-ditional or the modified technique that re-quired the rowers to lean back more when rowing. The higher power output would potentially translate into faster performance times, but whether the modified can be sus-tained during a whole rowing race and lead to improved performance is yet to be de-termined. References available on request.

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Can Health and Fitness Parameters Be Improved In Masters Athletes with a 10 Month Training and Nutrition Program PK. Doyle-Baker1, JK. Stewart1, AA. Ven-ner1,2. Faculty of Kinesiology1, Dept. of Medical Sciences2, U. of C., AB. Introduction Seniors have recently begun placing greater emphasis on their health and wellness. Many opportunities exist for general fitness and moderate to highly competitive ath-letic pursuits. Athletes who compete in the Masters categories include individuals who formerly competed in track & field in their younger years and those new to the sport. Nearly 60% of these participants are age 50 and older (USTFA 2005). Many Masters athletes have both the time and disposable income to pursue track & field competitions from the local to the national and interna-tional level. Therefore, there is a need to better under-stand health and fitness parameters of Masters athletes specifically competing in track and field. Much of the re-search in this area is on the effects of exercise with age. Few studies to date have examined whether the knowl-edge of pre-season testing results can alter the perform-ance and post-season results of Masters track & field athletes. It is unknown if providing the athlete with pre-season values can: 1) alter physiological and nutritional factors and 2) improve sport performance.

Objective The purpose of this study was to deter-mine: 1) the nutritional characteristics of the participants and 2) whether changes made to a Masters athlete (age ≥ 40 yrs) training program, based on pre-season physiological and nutritional measure-ments, would lead to improved sport performance and post-season results. Setting Human Performance Laboratory (HPL), U of C, Alberta. Participants A convenience sample of 10 Master ath-letes participated. There were males (n=6, age 57.8±8.1 yrs, BMI 24.1±3.6,

waist girth 86.8±11.4 cm) and females (n=4, age 57.5±13.4 yrs, BMI 20.6±1.9, waist girth 69.4±5.1cm). Athletes competed in track and field events ranging from 60m to full marathons and pentathlons. Methodology Body composition measurements were based on the Canadian Physical Activity, Fitness and Lifestyle Ap-proach (CPAFLA) protocol for height, weight, and waist circumference. Eligible participants (n=8) completed bone mineral density and additional body composition analysis determined by Dual Energy X-Ray Absorptiome-try. Muscular strength and endurance measurements were also evaluated by the CPAFLA health and fitness protocols for grip strength, push-ups, partial curls, flexi-bility, back strength, and leg power. Upper body endur-ance was measured with the YMCA bench test (see Ta-ble 1). Nutritional analysis based on a 3-day dietary re-cord was analyzed with the Food Smart 6.0 software pro-gram. Table 1: Subject Characteristics

Characteristic Mean (SD) Grip Strength (kg) M: 112.3 (22.7)

F: 54.8 (11.1) Push ups (number) M: 24.0 (8.1)

F: 18.0 (9.8) Sit and Reach (cm) M: 27.8 (10.6)

F: 34.3 (8.3) Partial Curl Ups (number/min)

M: 24.5 (10) F: 25 (0)

Vertical Jump (W) M: 4537.6 (1122.8); F: 1697.5 (388.1)

Back extension (sec) M: 180.0 (41.9) F: 180.0 (19.0)

YMCA bench press (number)

M: 26.5 (12.0) F: 26 (9.8)

% Body fat M: 17.1 (6.4) F: 21.2 (2.3)


Discussion/Conclusion Nutritional analysis supports that these athletes require further education to ensure they are consuming appro-priate macro- and micronutrients for their general health and training needs. Improving their current intake may improve their sport performance. References Available on request. Source of funding Sport Science Association of Alberta (SSAA) through the ASRPWF. For more information contact Dr. PK Doyle-Baker: 2500 University Drive NW, Faculty of Kinesiology, University of Calgary, Calgary, AB, T2N 1N4

Main Dietary Results There were no significant differences in daily mean (±SD) total calories (kCal) or grams per kilogram of body weight (g/kg) of carbohydrate (CHO), protein or fat. Athletes consumed a daily mean (±SD) of 2163±613 kCal, 3.94±1.29 g/kg of CHO, 1.45±0.42 g/kg protein and 1.00±0.47 g/kg fat. All athletes consumed the dietary reference intakes (DRI) of CHO and protein, but only one male consumed the endurance athlete recom-mended 6-10g/kg/d of CHO. Vitamin (Vit.) supplementa-tion occurred in 6 athletes. Vit. A and/or B3 were at or above the tolerable upper limit in 9 athletes. All athletes were deficient in at least 2 Vit. or minerals; folate (7 of 10) and potassium (6 of 10) were the most common.

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Pacing Strategy for 1500M Speed Skating BR MacIntosh, LJI Schmidt, AC Wind, FJ Hettinga, and JJ de Koning Human Performance Laboratory, Faculty of Kinesiology, University of Calgary and Faculty of Human Movement Science, Free University of Amsterdam Introduction Getting to the finish line first, requires a high capacity to provide energy and the ability to translate that energy to speed. In speed skating, performance can be quantified according to efficiency and the available energy from aerobic and anaerobic sources. Efficiency is the ratio of power output to the rate of providing energy. Power output is the power to overcome ice friction and air resistance. This depends on speed, ice conditions and body shape and position. With the knowledge of a skater’s efficiency and energy resources, it is possible to estimate the best skating strategy, such that all anaerobic energy is utilized before the end of the race (De Koning et al., 2005). The risk associated with this strategy is

that skaters may become fatigued before the end of the race, and this could be predicted to alter efficiency, slowing them down more than predicted. Objective In this study, we measured the efficiency and energy ca-pacities of speed skaters, and used a computer model to predict optimal performance based on distribution of energy through-out the time trial. Setting Human Performance Laboratory, and the Olympic Oval, Faculty of Kinesiology, University of Calgary, Alberta. Participants Eight national level male speed skaters (78.1 ± 5.9 kg) were recruited to participate in this project. Methods Individual efficiencies were estimated from submaximal skating trials with video analysis for calculation of power and portable metabolic system (Cosmed k4b2) to meas-ure oxygen uptake during the skating. Time trial 1 was conducted under race conditions to obtain the 1500m pacing strategy preferred by each skater.

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Subj VO2 (L/min)

VO2 (%VO2max)

Power Out-

put (W) Efficiency

(%)

1 - - - 18.9

2 2.90 88 193.7 19.1

3 2.72 78 183.3 19.3

4 3.34 100 211.6 18.2

5 2.91 79 168.5 16.6

6 2.86 84 199.6 20.0

7 2.93 78 197.4 19.4

8 2.51 85 170.4 19.7

Mean 2.88 85 189.2 18.9 SD 0.25 8 15.9 1.2

Another time trial was done with measurement of oxy-gen uptake to obtain individual time constants for the increase in oxygen uptake. Anaerobic capacity was esti-mated from the difference between power output of time trial 1, power output accomplished by oxidative energy. The latter was estimated from efficiency, and oxygen uptake kinetics from the submaximal trial and the second time trial. The computer model was then used to predict the best 1500m strategy for each athlete. Athletes were then given a training session to familiarize them with the optimal strategy for performance of the 1500m, before doing a final time trial in which they were expected to follow the optimal strategy. Main Results Results of the submaximal trial are given in Table 1. Times to complete 1500m time trials are given in Table 2. Although skaters obviously did not skate faster in the final time trial, their relative velocity profile (not shown) indicated they did try harder in the first half of the 1500m. Table 1. Individual data from submaximal trial

Table 2. Time trial results for 1500 m

Discussion/Conclusion The results indicate that skaters went slower when they tried to follow the optimal pacing strategy. There are several possible explanations for this result. The obvi-ous conclusion could be that fatigue affected their per-formance, and they were simply not capable of following the predicted optimal strategy. However, ice conditions may have contributed to the slower final time trial. We estimated ice friction, based on temperature, and other factors may have been relevant. Evidence for this is available from the relative velocity profile; athletes tried harder, but did not actually go faster in the early stages of the final time trial. This could only be explained if efficiency was different from the predicted values right from the start of the race, or there was a universal de-pression of energy availability (i.e. affecting almost every skater). Although we could not confirm the theory, the results do indicate that it is important to consider ice conditions more carefully in subsequent attempts to ver-ify the theoretical optimal pacing strategy. Reference De Koning, J.J., C. Foster, J. Lampen, F. Hettinga, and M.F. Bobbert (2005). Experimental evaluation of the power balance model of speed skating. Journal of Ap-plied Physiology, 98; 227-233.

Time Trial 1 Optimal Attempt Subject Finish time (s) Finish time (s)

1 111.45 115.07 2 118.44 118.50 3 113.63 115.65 4 111.66 114.92 5 113.51 116.58 6 113.83 115.62 7 115.63 115.55 8 123.94 124.79

Mean 115.26 117.08 SD 4.16 3.32

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A Re-Examination of the Relationship Between Sport-Based Perfectionism and Achievement Goal Orientations Among Youth Ice Hockey Players John K. Gotwalsa & John G.H. Dunnb aDepartment of Kinesiology, Texas Christian University, Fort Worth, Texas, USA bFaculty of Physical Education & Recreation, University of Alberta, Edmonton, Canada Introduction Recent reviews of the sport psychology literature (see Flett & Hewitt, 2005; Hall, 2006) have indicated that the personality trait of perfectionism is primarily debilitating within the context of sport. However, research within general psychology (see Stoeber & Otto, 2006) has indi-cated that perfectionism can also be healthy in nature. Hamachek (1978) explained the paradoxical nature of perfectionism by distinguishing between adaptive perfec-tionists and maladaptive perfectionists. Both types of perfectionists set extremely high standards for personal performance. Adaptive perfectionists tend to be realistic in their self-evaluations and are able to recognize that “perfect performances” are rarely achieved.

As a result, adaptive perfectionists are able to perceive success and experience a sense of satisfaction and enjoyment following perform-ance efforts (irrespective of whether mistakes are made). In contrast, for maladaptive perfec-tionists, failure to achieve a flaw-less performance is generally viewed as a complete failure. Moreover, maladaptive perfection-ists often have a tendency to believe that significant others (e.g., parents and coaches) are overly critical with respect to the perfec-tionists’ performances. Given that perfect performances rarely occur, maladaptive perfectionists seldom perceive success and rarely experience a sense of satis-faction or enjoyment following

performance. Similar to perfectionism, achievement goal orientations are motivational constructs that influence the way indi-viduals evaluate success in achievement settings (Nicholls, 1989). Nicholls identified two achievement goal orientations that he labeled task orientation and ego orientation. Task-oriented individuals define personal suc-cess and judge personal competence through the use of self-referent standards (Duda, 1993). As such, task-oriented athletes judge their competence upon personal effort and personal improvement. On the other hand, ego-oriented individuals define personal success and judge their personal competence on the basis of norm-referenced comparisons with others. In other words, for ego-oriented athletes, being better than others is the primary source of competence information. In sport, it has been suggested that being high in both task and ego orientations can be a useful motivational profile for high-performance athletes. Two studies (i.e., Dunn, Causgrove Dunn, & Syrotuik, 2002; Hall, Kerr, & Matthews, 1998) have examined the relationship between perfectionism and achievement goal orientations in sport. Both studies found a relation-ship between maladaptive perfectionism and high ego orientation. Dunn et al. found a relationship between adaptive perfectionism and high task orientation. However, neither study found any evidence of a relationship between adaptive or maladaptive perfection-ism and an achievement goal profile that was defined by high levels of both task and ego orientations.

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Objectives The purpose of this study was to re-examine the relationship between perfectionism and achievement goal orientation in sport. Design Correlational. Setting Hockey arenas within the Edmonton area. Participants A total of 153 male youth ice hockey players (Mean age = 13.28 years) participated in the study. All athletes competed on AA or AAA Pee Wee and Bantam hockey teams. Measures/Instruments Participants completed a demographic questionnaire, the Sport Multidimensional Perfectionism Scale 2 (Sport-MPS-2: Gotwals & Dunn, 2007), and the Task and Ego Orientation in Sport Questionnaire (TEOSQ: Duda & Nicholls, 1992). Main Results Canonical correlation (RC) analysis was used to examine relationships between perfectionism and achievement goal orientations. The predictor set was comprised of six Sport-MPS-2 subscales (personal standards, concern over mistakes, perceived parental pressure, perceived coach pressure, doubts about actions, and organization) and the criterion set was comprised of two TEOSQ subscales (task orientation, ego orientation). The analysis produced two significant canonical functions (RC1 = .46 and RC2 = .34, ps < .01). The first function showed a relationship between adaptive components of perfectionism (i.e., high personal performance standards and the tendency to use plans to govern behavior prior to and during competition) and an achievement goal profile characterized by high task and high ego orientations. These athletes also tended to perceive parents and coaches as providing performance pressures. The second canonical function indicated a rela-tionship between maladaptive compo-nents of perfectionism (i.e., high concern over mistakes, high doubts about actions, and high parent and coach pressures) and an achievement goal profile characterized by very high ego orientation and low task orientation. Conclusions The present results concur with previous research showing a relationship between maladaptive components of perfectionism

and an ego-centered achievement goal orientation. However, the present study also expanded upon past research by providing evidence of a relationship between a primarily adaptive profile of perfectionism and an achievement goal orientation in which both task (i.e., self-referenced) and ego (i.e., normative based) goals were endorsed by athletes. We speculate that adaptive perfec-tionists may be able to selectively choose the appropri-ate frame of reference by which to judge their perform-ance (i.e., task or ego goals) to maintain optimal levels of motivation in sport. In contrast, we speculate that maladaptive perfectionists only care about being better than others when judging their personal competence and self-worth. This latter motivational approach is danger-ous because being better than others is so often beyond the athlete’s control. Interestingly, both adaptive and maladaptive perfection-ists in this study identified pressures from parents and coaches regarding performance. While high performance standards are obviously important in competitive sport (and should be endorsed by parents and coaches alike), we would encourage parents and coaches to help young athletes understand that mistakes are an acceptable (and at times essential) part of the learning process in youth sport. Source of funding: Sport Science Association of Alberta (SSAA). For more information contact: Dr. John Dunn, Faculty of Physical Education and Recrea-tion, E-488 Van Vliet Centre, University of Alberta, Edmonton, AB, T6G 2H9.

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into the extent of the dietary and physical activity re-form that might be necessary for maintaining a healthy metabolic status. We hypothesized that trained women would have a lower threshold of energy availability com-pared to sedentary women described in the literature (Loucks & Thuma, 2003). Design Quasi-experimental design. Setting University of Alberta, Edmonton. Subjects Twenty-nine healthy, trained women (age=24.1±0.9 yr; VO2max=48.0±0.5 ml/kg/min) volunteered to participate in this study. Subjects participated in a wide variety of sports (eg cross-country running, cycling, field hockey, rowing, soccer) and were free from use of oral contra-ceptives and other medications known to alter hormonal status. This study was approved by a University Re-search Ethics Board. Intervention/Main Outcome Measures Leptin and insulin concentrations were measured during the follicular phase of the menstrual cycle in all partici-pants before and after 4 days of controlled exercise and energy intake. A brief description of the completed pro-tocol follows: total energy expended during cycle er-gometry for all subjects approximated 30 kcal/kg FFM/day at an intensity equivalent to just-below ventilation threshold. Supervised exercise sessions were per-formed in 30-minute bouts on a cycle ergometer with 10-minute rest periods until the required energy expendi-ture was reached. Energy availability was manipulated across 5 groups (5, 11, 19, 25, 40 kcal/kg LBM/day) by


Leptin and Insulin Response to Varying Energy Availability in Women V.J. Harber and C.S. Yarborough Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada Introduction Nutrition and physical activity have a profound impact on reproductive function and other metabolic processes. Most women benefit from regular exercise and experi-ence significant improvements in cardiovascular and muscular fitness. However, some women, in particular those involved in low body weight or aesthetically-demanding sports, deprive themselves of an adequate energy intake and increase their risk for developing men-strual disturbances (Loucks, 2004), reduced metabolic efficiency (Redman & Loucks, 2005) and reduced recov-ery from athletic performance (Harber et al, 1998). Inadequate energy availability (defined as dietary energy intake minus energy expended) results in reduced levels of numerous hormones including thyroid hormones, leptin, insulin and luteinizing hormone (Loucks & Thuma, 2003). These hormonal profiles are associated with re-productive irregularities, lower resting metabolic rate (RMR), reduced bone mineral density and impaired re-covery following exhaustive exercise (Redman & Loucks, 2005; Myerson et al, 1991; Harber et al, 1998). Seden-tary women have been shown to have a threshold of energy availability between 19 and 30 kcal/kg lean body mass (LBM)/day, below which the concentrations of these hormones drop significantly (Loucks & Thuma, 2003). Data from our lab show trained women experi-ence reductions in thyroid hormones at higher energy availabilities (Foster et al, 2000) which may suggest an increased susceptibility to the other metabolic condi-tions described above. Objective The purpose of this project is to characterize the func-tional relationship between energy availability and leptin and insulin metabolism in trained women to gain insight

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in exercise and less so to energy availability alone. Leptin, on the other hand, appears to be more sensitive to energy availability as supported by the observed de-crease. Source of funding: Sport Science Association of Alberta (SSAA) through the ASRPWF. For more information contact: Dr. Vicki Harber, Faculty of Physical Education and Rec-reation, E424 Van Vliet Center, University of Alberta, Edmonton, AB, T6G 2H9. Commentary The response of insulin and leptin to decreasing energy availability in trained women differs. Insulin appears to be most sensitive to the total amount of exercise per-formed whereas the leptin response may be more sensi-tive to change in substrate utilization in the face of lower total energy intake. Leptin concentrations dropped sig-nificantly in the energy availability groups below 19 kcal/kgFFM/day; this is the same threshold we identified for in reverse T3, a marker of energy insufficiency. Our find-ings suggest that energy availability for active women should remain above 20 kcal/kgFFM/day to avoid changes to leptin and potential metabolic adaptations associated with menstrual irregularities, altered metabolic status and decreased recovery in athletic females.

controlling energy intake with a liquid nutritional supple-ment (Ensure, Ross Labs, Quebec)(Loucks & Heath, 1994). For 7 days, beginning 2 days before the exercise protocol, a fasting blood sample was obtained once daily between 7:30-8:30 a.m. and analyzed for numerous thy-roid hormones. Baseline leptin and insulin concentra-tions were determined by pooling the samples from days 1-3 and subtracted from the hormone concentration on the morning of day 7. Main Results Statistical analysis of insulin revealed a main effect of time. Post-treatment levels of insulin were significantly lower compared to baseline concentrations in all energy availability groups (p<0.05). There were no differences between the energy availability groups. In contrast, analysis of leptin revealed an interaction between group and time; post-treatment levels of leptin decreased sig-nificantly in the 2 lowest energy availability groups (11 and 5 kcal/kgFFM/day) compared to baseline (p<0.05) and remained unchanged in the 3 higher energy availability groups. Conclusions Insulin levels declined significantly in all 5 energy availabil-ity groups whereas leptin only declined in the 2 lowest energy availability groups. These results suggest that insulin concentrations may be more sensitive to large acute increases

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The Effect of Reduced Carbohydrate Diet on Ammonia-Lactate Ratio at 102% of MLSS D.J. Smith and A. Petrie Human Performance Laboratory Faculty of Kinesiology, University of Calgary Introduction Depletion of muscle glycogen stores and the attenuation of blood lactate is a condition regularly observed after several bouts of endurance exercise on one day or after repeated high intensity bouts on consecutive days (1). However, the behavioural patterns of blood lactate and ammonia are qualitatively different where, at the same workload, lactate decreases while ammonia increases significantly (2).

Fig 1: Different effects of endurance training and glyco-gen depletion on blood lactate and NH3 in a GXT (Schulz and Heck, 2003). Objective The purpose of this study was to establish a test to de-termine if an athlete is in a reduced glycogen state by comparing the blood ammonia and lactate response to a 35 min cycling bout at approximately 102% of maximum lactate steady state (MLSS) power output in both a nor-mal and reduced carbohydrate (CHO) diet. Setting Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Alberta. Participants Six trained male cyclists (75.8 ± 8.7 kg) with a mean rela-tive MAP of 5.22 W·kg-1, and 57.0 ± 3.3 ml·kg-1·min-1 participated in a Neupert-Smith MLSS test (Neupert,

unpublished thesis, 2007) followed by a familiarization ride 1 (R1) and 5 (R2-6) additional cycling bouts at ap-proximately 102% ± 1.5 of MLSS over the course of 15 days. Methodology During R1 and R2 subjects followed a normal diet of 52% CHO with R3, 4 and 5 following a lower CHO diet of 45%, 40%, and 40% CHO respectively, concluding with R6 at a normal CHO diet of 54%. Serial blood samples were taken every 10 min starting at minute 5 during the 102% MLSS rides. Main Results

Fig 3: Response of lactate and NH3 in a typical subject in a reduced CHO state during constant load exercise at 102% of MLSS. The ammonia-lactate ratio at 35 minutes during R2 was 18.0 and increased to 25.7 at R5. It returned to 18.1 at R6 (normal CHO), demonstrating that there was a trend towards an increasing ratio during a lower CHO diet. Although none of the changes were significant, the lactate values decreased from 6.3 mmol·L-1 at 35 min of R2, to a low of 4.9 mmol·L-1 during R5 before returning to 6.2 mmol·L-1 for ride R6.

Fig 4: The mean ammonia lactate ratio at 35 minutes during each ride.

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y = 0.021x + 2.495R2 = 0.6806

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It can be concluded that there was a trend towards an increase in the ammonia-lactate ratio during a reduced glycogen state and these trends could be exaggerated with the application of an even lower carbohydrate diet. Thus, ammonia and lactate response during constant load exercise or as previous demonstrated in a GXT by Roeykens et al. (2) can be used to identify a reduced glycogen state.

References 1. Schulz, H. & Heck, H. (2003). Glycogen depletion as indication for ammonia determination in exercise testing. Eur. J. Sport Sci. 3(3):1-9. 2. Roeykens, J., Magnus, L, Rogers, R., Meeusen, R. & De Meirleir, K. (1998). Blood ammonia-heart rate relation-ship during graded exercise is not influenced by glycogen depletion. Int. J. Sports Med. 19:26-31.


normative data comparing different sports within a uni-versity varsity program. Objective Thus the purpose of this project is to evaluate the cur-rent pre-season aerobic, muscular and flexibility fitness of student athletes competing within the Canadian Inter-university Sport System at the University of Alberta. Design Cross-sectional descriptive design. Setting University of Alberta, Edmonton. Subjects The sample consisted of 177 female and 125 male Uni-versity of Alberta varsity athletes competing in the fol-lowing Canadian Inter-University Sport: Basketball (Men-Women), Volleyball (Men-Women), Hockey (Men-Women), Field Hockey (Women), Soccer (Men-Women), Rugby (Women), Swimming (Men-Women), Wrestling (Men-Women) and Tennis (Men-Women). This study was approved by a University Research Ethics Board.

State of the Student Athlete: Evaluation of Pre-Season Fitness Michael D. Kennedy Faculty of Physical Education and Recreation University of Alberta Edmonton, Alberta, Canada Introduction A recent report of pre-season conditioning in high school athletes (Brooks et al. 2007) determined that only 33 % of athletes had adequate aerobic, strength and flexibility fitness. At the university level, most universities and colleges provide a pre-participation evaluation (PPE) which is a medical survey primarily designed to evaluate conditions that might adversely affect an athlete during sports participation (Joy et al. 2004). However, a PPE does not adequately address the fitness of the athlete despite the fact that fitness is integral to injury preven-tion (Feiring & Derscheid, 1989) as well as sport per-formance (Maughan, 2005). Currently, there is a paucity of research describing the fitness status of student ath-letes competing in university sports or published

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Measurement Male Average

Female Average

Height (cm) 183 168.6 Weight (kg) 83 68.5 Vertical Jump (cm) 59 45.3 Sit & Reach (cm) 35.0 39.0 Curlups (max #) 32 32 Push ups (max #) 29 12 Combined Hand Grip (kg) 120 80 40m Sprint (seconds) 5.63 6.40 Illinois Agility (seconds) 11.03 11.70 Leger Shuttle run (stage) 10 8.5

pVO2max (ml/kg/min) 53 49.4


Conclusions These fitness test results describe the fitness status of male and female varsity athletes across the full spectrum of ice, court, field and individual sports played at the uni-versity level. These observations provide significant in-sight into the deficits and strengths of varsity athletes in preparation of their competitive season. In summary, muscular endurance in the abdominals (core strength) was poor in both male and female varsity athletes, and upper body strength in females needs improvement for both health and performance reasons. In addition, the predicted aerobic fitness of varsity athletes is not much better than an active male or female university student. It can be concluded that despite excellence in sport spe-cific environments, the general preparedness of varsity athletes for a competitive season is not enough. Source of funding: Sport Science Association of Alberta (SSAA) through the ASRPWF. For more information contact: Dr. Michael Kennedy, Faculty of Physical Education and Recreation, E-488 Van Vliet Center, University of Alberta, Edmonton, AB, T6G 2H9. Commentary This project is a first step in a multidisciplinary approach to improving the health of student athletes at the Uni-versity of Alberta. This research has provided important normative data to the Athlete Health Team at the Uni-versity of Alberta as well as help determine common deficits in varsity athletes. It also has provided some im-portant sport science coach education, whereby all coaches were provided with summaries of their team’s strengths and weaknesses and direction for physical training in the competitive season. A number of varsity programs have already applied these results to their training programs. This research has provided a founda-tion for longitudinal comparisons of athlete development that will be athlete specific. The long term goal for physi-cal preparation of University of Alberta varsity athletes will be to provide individualized training programs for both off-season and pre-season preparation. As well to achieve a multi-disciplinary athlete health approach future assessments will incorporate clinical measures of musculoskeletal health, and inventories related to nutri-tional status, recovery and stress. In summary this research provided some significant insight into varsity athlete preparedness and has provided important descriptive information that will be used for future research and student learning opportunities.

Intervention/Main Outcome Measures Data was collected from August – October 2007, de-pendent on the start of each sports competitive season. Anthropometric data including height and weight were collected first followed by a standardized battery of field tests which included vertical jump, 40 m sprint, modified Illinois agility test, grip strength, sit-ups, triceps pushups, sit and reach, and the Leger 20 m shuttle run. Main Results A summary of average scores for both genders on each measure are shown in table 1. Men were significantly better in vertical jump, pushups, handgrip, 40 m sprint and shuttle run stages completed. The female athletes had better sit and reach scores and the same average number of curlups completed as the male athletes. The predicted VO2max score (based on Leger shuttle) was similar for male (53 ml/kg/min) and female participants (48 ml/kg/min). Table 1: Means and range for each measure in both male and female participants.

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(age 10-12) to level 6 (aged 16 up) in both provincial and national streams. Most often the Moy is first taught from a support swing but eventually from a straight body downswing from handstand when the goal is to catch the skill in support (Figure 1). This downswing resembles that of the downswing in back giants on horizontal bar and is therefore used as a precursor to giants on parallel bars (Figure 2). Figure 1. Moy from handstand to support Figure 2. Giant swing backwards As the gymnast grows both in skill and stature he must contend with the height constraint imposed by the bars. This is generally manifested in a bent knee swing through the bottom of the swing. Prassas (2005) and Tsuchiya et. al. (2004), using college level gymnasts, both suggested close technique similarity between giants on horizontal bar and parallel bars ex-cept for this knee bend. This is also seen in the Moy using the ‘giant downswing’. However a further progres-sion of the Moy is a Tippelt or Moy piked. (Figure 3) Figure 3. Moy piked (figures taken from FIG Code of Points, 2006)

Release Characteristics of the Long Hang Swing Uprise, Moy and Back Giant Swing on Parallel Bars in Men’s Artistic Gymnastics P. Gervais Faculty of Physical Education and Recreation University of Alberta Edmonton, Alberta, Canada Introduction The cast to support on parallel bars has long been used as a transition skill from under-bar swings to backward swings in support. More recently the Moy has replaced the cast as the primary transition skill taught in Canadian Gymnastics. The Moy is either a required element or a development skill required in competitive boys level 3

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The angle of incidence is the angle formed between a right horizontal, the wrists and the body’s CM. Both sub-ject 1 and 3 kept straight legs during their Moys due to no height restriction and a piked hip respectively. All subjects had similar shoulder and hip angles in their gi-ants. Conclusions Tsuchiya et. al. (2004) discussed the importance of shoul-der flexion during the up swing following shoulder ex-tension during the tap in the bottom of the swing. Sub-jects 1 & 2 had greater similarity between their positions at maximum H with noted differences in the hips in the giants. The shoulders aremore flexed in the Moys in preparation for release where the hips are fully ex-tended in all cases. However, the Moy piked had the least shoulder flexion than any of the skills. Source of funding: Sport Science Association of Alberta (SSAA) through the ASRPWF. For more information contact: Dr. Pierre Gervais, Faculty of Physical Education and Recreation, E424 Van Vliet Center, University of Al-berta, Edmonton, AB, T6G 2H9. Commentary This case study provided evidence of good similarity be-tween the giants and the developmental skill (Moy) but not the more advanced Moy piked.

Objective The purpose of this study was to look at the Angular Momentum ( H ) characteristics of these 3 potential Moy downswings, no height constraint, back-giant and Moy piked and to compare these individual Moys to their gi-ant technique used on parallel bars. Design Case study - quasi-experimental design. Subjects Three National level Junior male gymnasts volunteered and gave informed consent to participate in this study. Intervention/Main Outcome Measures 3D data was collected using 4 Qualysis ProReflex cam-eras operating at 120Hz. Since the parallel bar rail ob-scures the wrist during some of the downswing, the wrist was also manually digitized using the APAS system and a synchronized video record (60Hz). H, taken about the wrist, was normalized by dividing the subject’s mass times the square of their height (Hinricks et. al. 1983). Main Results The purpose of the downswing is to create the neces-sary conditions for release and catch with sufficient mo-mentum for a smooth transition into the next element. Table 1 lists the H maximums, where they occur in the downswing and the body configuration at those points. Table 1 Angular Momentum

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Documents

Fall 2008