Pulse

Fall 2013 Sport Science Edition

Pulse Fall 2013

SMCA Board of Directors Ray Kardas - President

Dexter Nelson - Past President

Steve Johnson - Vice-President

Alex Yaworski - Secretary

Miranda Sallis - Treasurer

Stephane Simard - Member at Large

Heather Brady - Member at Large

SMCA Employees Barb Adamson - Executive Director

Penelope Beardsley - Bookkeeper

Pulse Magazine Published by: Sport Medicine Council of Alberta

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Contents copyright 2013 by SMCA.

Articles/abstracts 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

2 Fall 2013

Inside this issue:

Perfectionism and Perceptions of Social Loafing in Youth Soccer Players

4

Vitamin D Knowledge Awareness and Behaviours Associated with Sunlight in the Elite Minor Hockey Community in Calgary, Alberta

6

Parents’ and Coaches’ Responses to Game Situations in University Sport

8

The Use of a Pre-season Questionnaire and Baseline Neurocognitive testing to help Predict Subsequent Risk for Concussion in Collegiate Athletes

9

Does Caffeine Ingestion influence the Metabolic, Cardio-respiratory or Catecholamine response to a 1 km Time Trial in Cyclists?

10

Inside Pulse…

3 sportmedab.ca

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4 Fall 2013

Introduction Social loafing has been defined as the reduction in a person’s moti-vation and effort that occurs when an individual works collectively on a task compared to when working alone or coactively on a task (Karau & Williams, 1993). This reduction in effort in team or group settings (when maximum individual effort is expected) can have debilitating effects upon group performance. Indeed, in the con-text of team sports where team members are trusting that all teammates are giving maximum effort towards the achievement of the team’s goals, social loafing can be particularly problematic and can seriously undermine a team’s chances of competitive suc-cess (Hardy, 1990). Understanding factors that can influence social loafing in sport is therefore an important research endeavor in applied sport psychology where a primary goal of researchers and practitioners is to find ways to maximize athletic performance whether at the individual or team level.

Although research indicates that a number of factors influence the degree to which people engage in social loafing (e.g., individual identifiability, accountability, perceived task value, team cohe-sion), a few studies have shown that personality traits may play a role in the social loafing process; these include achievement goal orientations (Swain, 1996), conscientiousness (Ferrari and Pychyl, 2012), and protestant work ethic (Smrt & Karau, 2011). A personal-ity trait that has never been studied with respect to social loafing is perfectionism. Perfectionism is a particularly important achieve-ment-motivation trait to examine among athletes because it has been associated with a wide variety of cognitive, affective, and behavioral correlates in sport (see Stoeber, 2011) that can poten-tially influence performance.

Perfectionism is defined as a multidimensional achievement-motivation disposition (Hewitt & Flett, 1991). Although many defi-nitions of perfectionism exist in the literature, researchers gener-ally agree that the core feature of perfectionism is an individual’s tendency to set and strive for the flawless attainment of ex-tremely high performance standards (Stoeber, 2011). Although many facets (or components) of perfectionism have been pro-posed in the literature (see Enns & Cox, 2002), these facets can be

classified under two overarching dimen-sions of perfectionism: namely, perfection-ist strivings and perfectionist concerns. Perfectionist strivings represent the de-gree to which people strive to attain their lofty performance goals, whereas perfec-tionist concerns reflect the degree to which people become concerned or wor-ried about the consequences of failing to achieve these goals. People who have high perfectionist strivings combined with high perfectionist concerns are labeled as maladaptive or unhealthy perfectionists. People who have high perfectionist striv-

ings combined with low perfectionist concerns are labeled as adaptive or healthy perfectionists (Stoeber & Otto, 2006).

Maladaptive perfectionists are driven by the need to avoid failure and the need to avoid criticism. As such, their self-worth is contin-gent upon achieving these goals. In contrast, adaptive perfection-ists are driven by the need to succeed and are generally much less afraid of failure and public criticism (than maladaptive perfection-ists). Given that social-loafing theorists have suggested that peo-ple often socially loaf in order to avoid the possibility of being blamed for individual or team failure (Karau & Williams, 1993), it is seems reasonable to expect that increased maladaptive perfec-tionist orientations may predispose athletes to engage in or en-dorse the use of social-loafing behaviours in their sport.

Objectives The purpose of this study was to determine if youth soccer play-ers’ perfectionist orientations were related to their perceptions of social loafing. The sport of soccer was chosen because it offers many opportunities for athletes to socially loaf in both competi-tion and training settings.

Design Correlational

Setting Soccer training facilities in Alberta.

Participants The sample consisted of 216 male and female Under-16 Tier I/II youth soccer players (M age = 15.25 years, SD = .63).

Measures/Instruments Participants completed a measure of perfectionism in sport (the Sport Multidimensional Perfectionism Scale [Sport-MPS-2]: Gotwals & Dunn, 2009) and two measures of perceived social loafing in sport: the Perceived Social Loafing Questionnaire (PSLQ: Høigaard, Säfvenbom, & Tønnessen, 2006) and a newly developed instru-ment that was labeled the Social Loafing Acceptability Questionn-

Perfectionism and Perceptions of Social Loafing in Youth Soccer Players

John G.H. Dunn & Matt Vaartstra

Faculty of Physical Education & Recreation, University of Alberta, Edmonton, Canada

5 sportmedab.ca

aire (SLAQ). The PSLQ measures the degree to which players feel that their team-mates engage in social loafing behaviours, whereas the SLAQ measures the de-gree to which players approve of the social loafing behaviours of others in their sport.

Main Results Canonical correlation analysis revealed two significant canonical functions (RC1 = .35; RC2 = .30, p < .005). The first canonical function revealed a profile of maladap-tive perfectionism (i.e., high personal standards, high perceived parental pressure, high doubts about actions) that was positively correlated with dysfunctional per-ceptions of social loafing (i.e., heightened tendencies to view teammates as so-cially loafing and heightened tendencies to approve of social loafing behaviours). In contrast, the second canonical function revealed a profile of adaptive perfec-tionism (i.e., high personal standards, high organization, low perceived parental pressure, low doubts about actions) that was positively correlated with more func-tional perceptions of social loafing (i.e., heightened tendencies to view teammates as socially loafing but decreased tendencies to be accepting of such behaviours).

Conclusions Results indicate that increased maladaptive perfectionist tenden-cies may predispose youth soccer players to view social loafing behaviours as acceptable in the training environment. In contrast, increased adaptive perfectionist tendencies may predispose ath-letes to become less accepting of social loafing behaviours in the training environment. Interestingly, increased maladaptive and adaptive perfectionist tendencies both appear to predispose youth soccer players to believe that teammates engage in social loafing. Perfectionist orientations appear to play a role in the so-cial loafing process in youth soccer, indicating that coaches may benefit from being aware of their athletes’ perfectionist orienta-tions (in order to understand why some athletes hold back from giving maximal effort at times when maximal effort is needed for team success).

Source of funding:

Sport Science Association of Alberta (SSAA).

For more information contact:

Dr. John Dunn, Faculty of Physical Education and Recreation, E-488 Van Vliet Centre, University of Alberta,

Edmonton, AB, T6G 2H9.

Introduction

A large population of Canadians partici-pates in ice hockey, which is often played year round at the elite level. The season for elite level bantam and minor midget (ages 13-15) runs from August to March, which is followed by spring and summer development camps. Both par-ents and coaches of these ath-letes are at high risk for vitamin D (VD) deficiency due to the increased amount of time spent indoors and they are likely un-aware of this. Physical and bio-logical risk factors for VD inade-quacy are known; however, population-specific behaviours and attitudes that influence these risk factors, particularly among the athletic community are poorly documented. The published studies, of which there are only a few, on popula-tion specific knowledge of VD show incomplete and confused knowledge, with behaviours that would lead to VD insuffi-ciency. Athletic communities and males are underrepre-sented in the published litera-ture.

Objective

We undertook a KAP survey to investigate the knowledge level of VD awareness and behav-iours associated with hours of sunlight in parents (P) and coaches (C) of elite youth ice hockey players living in Calgary, Al-berta.

Design

Descriptive, Cross-sectional survey

Setting

Arenas servicing Bantam AA, Bantam

AAA and Minor Midget AAA ice hockey teams around Calgary and surrounding area.

Subjects

Overall 17 teams participated (53%), with 36 coaches (97% males), and 92 parents

(51% males) completing surveys. The av-erage age was 41.74±9.5 years with 82 males and 46 females (N=128). The par-ticipants were predominantly Caucasian (96.9%) with a very small percent being East Asian (3.1%). The majority of partici-pants (57.8%) had a college or university degree or some college or university (21.9%). 66.3% of the players participated in spring and 17.2% in the summer ice hockey league as reported by parents.

Intervention/Main Outcome Meas-ures

The outcomes measured were knowl-edge and behaviour. Knowledge was analyzed through linear regression based on correct answers to 6-questions scored out of 8; each correct answer was given a

score of 1 and an incorrect re-sponse was given a 0. Behaviour was measured by hours of sunlight exposure and sun-screen use. The 31 question sur-vey was completed on iPads saved as individual PDFs, downloaded onto an excel docu-ment and exported into SPSS (V20) for analysis. Frequency distributions were determined for each question, as well as bro-ken down into percent by posi-tion (C or P) and sex (M or F). Chi-squared analysis was used to make comparisons between sex, position and education.

Main Results

All of the participants indicated that they had heard of VD and the majority knew that VD is absorbed from sunlight through the skin (95.3%). Overall 42% indi-cated that they had enough ex-posure to sunlight and C were more likely to think they had enough exposure (52.8%) com-pared to P (38%) (p = 0.129). 80.5% of participants knew that

VD was associated with bone health; however, females were more likely than males to know this (93.5% vs. 73.2%, p=0.005). The majority of the partici-pants indicated that 15-30 minutes in the sun was needed to absorb sufficient VD (29.7%), 21% indicated 30-45 minutes, 22.9% indicated 60 minutes and 18% indi-cated that more than one hour was needed. See Table 1 for participant’s rat-ing of VD sources.

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Vitamin D Knowledge Awareness and Behaviours associated with Sunlight in the Elite Minor Hockey Community in Calgary, Alberta

PK Doyle-Baker, EM Hidlebrandt, A Lunz

Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.

7 sportmedab.ca

Table 1. Participant’s rating of vitamin D sources (n, %)

Most participants indicated that they learned about VD through the media (70.3%) or a physician (60.2%). Interestingly 76.6% of participants indicated that they used sunscreen products >15 SPF with most wearing it 1-2 days per week during both summer and winter (34.4% and 64.1%).

Future Research Can ice hockey players maintain sufficient VD during the fall thru to spring? Does insufficient VD status increase risk for frequent illness in athletes? Does VD status influence injury risk during athletic training or competition?

Source of Funding: Sport Science Association of Alberta (SSAA) through the ASRPWF.

Contact: Dr. PK. Doyle-Baker, University of Calgary, 403-220-7034, pdoyleba@ucalgary.ca

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Source 1 (most) 2 3 4 5 (least)

Supplement 19 (14.8) 54 (42.2) 26 (20.3) 17 (13.3) 12 (9.4)

Sunshine 94 (73.4) 23 (18) 3 (2.3) 0 (0) 8 (6.3)

Milk 5 (3.9) 31 (24.2) 44 (34.4) 24 (18.8) 24 (18.8)

Tuna 6 (4.7) 4 (3.1) 18 (14.1) 51 (39.8) 49 (38.3)

O. Juice 4 (3.1) 16 (12.5) 37 (28.9) 36 (28.1) 35 (27.3)

Conclusions

The results of this survey demonstrate the current trends in knowledge and behaviour in this specific at risk population. It also highlights the increased amount of time spent indoors due to hockey. Overall there is high awareness of VD and its effects; however, the specific sources of dietary VD are less well recog-nized. Females are more likely to know about VDs effect on bone health, which could potentially be due to their knowledge of their increased risk of osteoporosis. However, even though these females have knowledge of this they are still more likely to spend less time outdoors absorbing VD to aid in their bone health. These P and C are obviously at high risk of VD insuffi-ciency due to their increased amount of time spent indoors as well their decreased absorbance in the winter months based on the latitude at which they live. A study strength was the utilization of the iPad format which decreased both the administration and participant burden with an approximate survey completion time of 3 and ½ minutes. A potential selection or non-response bias could have occurred as some individuals may have chosen to not participate due to the voluntary nature of the study.

8 Fall 2013

Source of funding: Sport Science Association of Alberta (SSAA) through the ASRPWF.

For more information contact: Dr. Nicholas Holt, Faculty of Physical Education and Recreation, Van Vliet Center, University of Alberta, Edmonton, AB, T6G 2H9. Tel: 780-492-7386. E-mail: nick.holt@ualberta.ca

Commentary Little is known about how parents and coaches respond to changing game circumstances. Focusing on a university volleyball team, we measured parents’ and coaches’ heart rate re-sponses during a regular season game. Participants’ heart rates gen-erally increased as the game progressed, with observed peaks in heart rates coinciding with certain critical game incidents (e.g., mis-takes, injury, and toward the end of sets/the game). These findings suggest a physiological response to critical incidents during games. Further research is needed to examine how these physiological re-sponses may be linked with psychological constructs and behavior.

Introduction Parents and coaches can have an important influence on athletes’ experiences and per-formance during competitions. Likewise, watching their children/athletes compete also has an influence on parents and coaches, and their behaviors appear to change in relation to game circumstances (Holt, N. L., Tamminen, K. A., Black, D. E., Sehn, Z. L., & Wall, M. P. (2008). Parental involvement in competitive youth sport set-tings. Psychology of Sport and Exercise, 9, 663-685). However, little is known about how and why parents and coaches respond to changing game circumstances. Under-standing more about their physiological re-sponses (i.e., heart rate) may help to shed more light on these issues.

Objective The objective of this study was to examine how parents and coaches’ heart rates changed in relation to game cir-cumstances in high-performance (university) sport.

Setting University of Alberta, Edmonton.

Subjects Participants were recruited from a university volleyball team. There were four coaches (2 female, 2 male) aged 25-59 yrs and five par-ents (3 fathers, 2 mothers, aged 53-60 yrs).

Measures Data were collected during one regular season game. Heart rates were measured with Suunto Dual Comfort Heart Rate Belts (Vantaa, Finland)

and transmitted in real time to a Suunto Team Pod connected to a laptop computer loaded with Suunto Team Manager-Monitor (v. 2.1.2) software. The game was video re-corded in order to identify critical incidents (e.g., disputes with referee, injuries, long rallies). Heart rate data were mapped chronologically with the game tape. Individ-ual and group responses were calculated. Changes in participants’ heart rates and cor-responding game situations were identified and examined idiographically.

Results Sufficient data for analysis was obtained from the four coaches and two parents (equipment malfunctions produced incom-plete data sets for the other three parents). It was a close game, which the team studied

won in five sets. In general, the partici-pants’ heart rates increased between 10 and 20bpm over the course of the game. We also observed heart rate changes in relation to certain critical incidents. For example, parents and coaches showed peaks in their heart rate in relation to an injury to one of the players, a number of officiating decisions, poor execution of skills/strategy by the team (e.g., letting a ball drop to the ground), and long rallies (especially towards the end of a set). Addi-tional changes to coaches’ heart rates were observed when decisions were being made regarding substitutions and during time-outs.

Idiographic analyses revealed individual differences in participants’ responses. For example, the head coach’s heart rate in-creased gradually until the end of the fourth set. Then, in the fifth set, there was a rapid increase of over 10 bpm as the game was ‘on the line.’ In contrast, the

heart rate of the least experienced assistant coach fluctuated throughout the game but showed only a negligible increase from the beginning to the end of the game.

Additionally, the extent to which participants responded to critical incidents varied. For example, the head coach showed more heart rate changes in relation to poor perform-ances or errors during games than the par-ents or two of the assistant coaches. Simi-larly, one of the assistant coaches had more variability in her heart rate when she was required to provide feedback to athletes.

Parents’ and Coaches’ Responses to Game

Situations in University Sport

N. L. Holt, C. J. Knight, J. G. H. Dunn, & M. D. Kennedy Faculty of Physical Education and Recreation,

University of Alberta, Edmonton, Alberta, Canada.

Conclusions Critical incidents during games were associated with physiological responses (as measured by heart rate). There were individual differences in these responses, particularly among the coaches. Notably, the head coach demonstrated more dynamic changes in heart rate, which may reflect her level of investment in the team/game (she was a full time coach whereas the other coaches were part-time or volunteers). Such changes in heart rate may be an indicator of stress and/or anxiety, and therefore these findings suggest it may be valuable to teach coping strategies to deal with specific critical incidents during games. But, given the indi-vidual variations we observed, it is likely that such coping strategies should be tailored to meet individual needs.

Results of this study suggest further research in this area is war-ranted. Given we observed changes in heart rate in relation to game circumstances, to build on the current research future studies should include measures of psychological and behavioral con-structs. In particular, it would be important to monitor parents’ and coaches’ perceptions of stress/anxiety and behavioral changes in their communication with athletes (for coaches in particular).

Introduction The evaluation and treatment of athletes who sustain mild head injuries has evolved considerably in the past two dec-ades. The current approach is multifac-eted, and involves measurement of the presence and severity of symptoms, cog-nitive testing, and assessment of balance. Neurocognitive testing has become a fun-damental and practical method for evalu-ating subtle neurocognitive sequelae fol-lowing a concussion.

The purpose of this project was to investi-gate clinical issues associated with sports related concussions in male and female collegiate athletes, in a variety of contact sports. If predictive factors and/or predis-posed athletes could be identified, then preventative strategies could be formu-lated, implemented and further studied to assess impact.

Objective To identify potential variables through the computerized neurocognitive Imme-diate Post-Concussion Assessment and Cognitive Test (ImPACT®) that might pre-dict higher incidence of sport-related con-cussion, and more adverse outcomes (prolonged recovery). To identify potential variables through a Pre-Season Concussion questionnaire that might predict higher incidence of sport-related concussion, and more ad-verse outcomes (prolonged recovery).

Design Cross-sectional

Setting University of Alberta, Edmonton.

Subjects Varsity athletes in contact and collision sports (hockey, football, rugby, soccer, basketball and wrestling) at the University of Al-berta: 356 athletes (218 males, 138 females) mean age of the athletes was 20.02 years (range 16 to 28 years of age)

Intervention/Main Outcome

Measures Athletes completed pre-season question-naires and baseline concussion screening using both SCAT2 and ImPACT® over three varsity seasons, from 2010-11 through 2012-13. The baseline composite scores from ImPACT® (Verbal Memory, Visual Mem-ory, Visual Motor Speed, Reaction Time and Total Symptom Score or TSS) and sport-related concussions incurred over the course of the study, were used as out-come measures.

Main Results During the 2.5 year period, 42 (11.8%) ath-letes suffered a concussion. In a Pearson Chi Square Test comparing athletes who scored in the lowest 25th percentile com-pared with the highest 25th percentile at baseline on ImPACT®, more athletes scored in the lower group for Visual Mem-ory, but this did not reach statistical sig-nificance. For the remaining composite scores, more athletes who suffered a con-cussion scored in the top 25th percentile than the lower 25th percentile. However, these results were not statistically signifi-cant. Athletes who suffered a concussion did report higher TSS (top 25th percentile) at baseline, than athletes who did not get injured. An odds ratio of 1.04 for the risk of concussion was calculated for every 1 point increase in TSS on ImPACT®.

sportmedab.ca 9

Conclusions In this study, Total Symptom Score (TSS) at baseline, on ImPACT® testing did help to identify varsity athletes who went on to suffer a concussion. The additional compos-ite baseline scores from ImPACT® were not significantly lower for athletes who incurred a concussion than for those who did not. ImPACT® may potentially be a valuable tool for distinguishing subtle neurocognitive deficits, both at baseline, and when making return to play decisions. Sport medicine pro-fessionals should be aware of the limitations of this tool, take a thorough pre-season medical history and instruct athletes in con-cussion prevention strategies.

Source of Funding: Sport Science Asso-ciation of Alberta (SSAA) through the ASRPWF.

For more information contact Dr. Constance Lebrun, Department of Medi-cine and Dentistry, University of Alberta. ConnieLebrun@med.ualberta.ca

Commentary

The Pre-participation Physical Examination (PPE) is a routinely carried out at the recrea-tional, collegiate and professional levels. It offers an opportunity to screen for disease, and to carry out baseline testing. This study did not find any significant variables in the questions asked of the varsity athletes. It is still recommended that a PPE be completed prior to each athletic season to screen for previous injuries and illnesses. It is possible that additional questions might be more sensitive in identifying athletes who may be of an increased risk of concussion during the season and/or prolonged recovery.

The Use of a Pre-season Questionnaire and Baseline Neurocognitive testing to help Predict Subsequent Risk

for Concussion in Collegiate Athletes

Constance Lebrun, Martin Mrazik, Joan Matthews-White, Dhiren Naidu, Nicole Lemke.

Department of Medicine and Dentistry, Department of Educational Psychology, Faculty of Physical Education and Recreation,

Department of Physical Medicine and Rehabilitation University of Alberta, Edmonton, Alberta, Canada.

Fall 2013 10

Does Caffeine Ingestion influence the Metabolic, Cardio-respiratory or Catecholamine response to a 1 km Time Trial in Cyclists?

Dan Syrotuik, Ph.D., Dean Cordingley, M.Sc. & Gordon Bell, Ph.D. Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada.

ABSTRACT

Background It has been shown that caffeine can im-prove various physiological and psychologi-cal aspects of exercise, but these effects have been most notably associated with aerobic endurance exercise (Graham, 2001). However, the effect of caffeine on short duration, high intensity, anaerobic exercise such as that performed during a 1 kilometer cycling time trial has not been adequately investigated (Davis and Green, 2009). The role that caffeine plays in altering pain per-ception, fatigue perception and potassium concentrations in the blood as an indication of an altered sodium/potassium electro-chemical gradient in the muscle during high intensity, anaerobic exercise was recently reported by the investigators (Cordingley et al., (2012). In this latter study, it was shown that there was a greater increase (P<0.05) in blood lactate and potassium concentra-tions after a 1 km time trial when caffeine was ingested in comparison to a placebo but no other differences were observed. It has also been noted that caffeine may

increase the release of catecholamines (epinephrine, norepinephrine; Jackman et al., 1996) in the blood which are known to stimulate anaerobic glycolytic energy pro-duction as well as increase cardiovascular responses to exercise such as heart rate. The investigation of these latter changes was the intent of this study.

Objective The research in this study was a follow-up to a previously funded SSAA project by the principal investigators and investigates new hypothesized variables. Thus, the purpose of this study was to determine the meta-bolic, cardio-respiratory and catecholamine responses to a 1 km time trial performance in Alberta cyclists. It was hypothesized that caffeine would promote a greater meta-bolic response, higher heart rate and in-creased circulating concentration of epi-nephrine and norepinephrine in comparison to placebo.

Design Two group, randomized, cross over, double blind study.

Setting University of Alberta, Edmonton.

Subjects Ten trained male cyclists from the Edmon-ton area that signed consent that was ap-proved by Research Ethics Board.

Intervention/Main Outcome

Measures The cyclists were required to come to the lab for 3 sessions. The first was for an aero-bic power test (VO2max) on a cycle ergome-ter and a practice 1 km cycling time trial (TT) on a Velotron stationary cycle. The second and third sessions included 1 km cycling time trials, 1 week apart, and after con-sumption of either caffeine (5 mg·kg-1 body mass; Caf) or a placebo (Pla) non-caloric fruit flavored drink in a random order. Metabolic measurements, pulse oximetry, heart rate and blood samples were taken before, during and after each 1 km cycling time-trial. Epinephrine and norepinephrine were determined using a commercially available ELISA (Rocky Mountain Diagnos-tics).

11 sportmedab.ca

Main Results Oxygen consumption and HR was increased and SpO2 decreased (P<0.05) during the 1 km TT. However, there was no difference in peak VO2 (Pla = 51.7 ± 3.4 vs. Caf = 51.5 ± 3.0 ml/kg/min) peak HR (Pla = 170 ± 13 vs. Caf = 171 ± 12 b/min) or SpO2 (Pla = 94 ± 4 vs. Pla = 94 ± 5 %) between conditions. Epinephrine and norepinephrine were elevated as result of the 1 km TT and both were significantly higher after caffeine consumption versus placebo. Figure 1. Plasma epinephrine concentration before and after the 1 km cycling TT. Values are means ± SD. Figure 2. Plasma norepinephrine concentration before and after the 1 km TT.

Articles for this Pulse

provided by the

Sport Science

Association of Alberta

Conclusion Caffeine supplementation produced a significantly greater in-crease in circulating levels of catecholamine production during a 1 km cycling time trial.

Source of funding: Sport Science Association of Alberta (SSAA) through the ASRPWF.

For more information contact: Dr. Dan Syrotuik (dan.syrotuik@ualberta.ca).

Commentary Caffeine is widely used by athletes as an ergogenic aid but the potential benefits to anaerobic exercise performance are contro-versial. Despite a higher excitable state as evidenced by greater catecholamine concentration after caffeine consumption, there were no changes in heart rate, oxygen consumption or oxygen saturation. Thus, if an athlete is looking for a greater level of excit-ability prior to anaerobic exercise, caffeine will do this, but likely not improve 1 km cycling time trial performance.

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