Jonathon R. Fowles

Relationships to skating performance in competitive hockey players.

The purpose of this study was to identify off-ice variables that would correlate to on-ice skating sprint performance and cornering ability. Previous literature has not reported any off-ice testing variables that strongly correlate to on-ice cornering ability in ice hockey players. Thirty-six male hockey players aged 15–22 years (mean ± SD: 16.3 ± 1.7 years; weight = 70.8 ± 10.4 kg; height = 175.6 ± 4.1 cm) with an average of 10.3 ± 3.0 years hockey playing experience (most at AA and AAA levels) participated in the study. The on-ice tests included a 35-m sprint and the cornering S test. The off-ice tests included the following: 30-m sprint, vertical jump, broad jump, 3 hop jump, Edgren side shuffle, Hexagon agility, side support, push-ups, and 15-second modified Wingate. The on-ice sprint test and cornering S test were strongly correlated (r = 0.70; p > 0.001). While many office tests correlated with on-ice skating, measures of horizontal leg power (off-ice sprint and 3 hop jump) were the best predictors of on-ice skating performance, once weight and playing level were accounted for. These 4 variables accounted for a total of 78% (p > 0.0001) of the variance in on-ice sprint performance. No off-ice test accounted for unique variance in S-cornering performance beyond weight, playing level, and skating sprint performance. These data indicate that coaches should include horizontal power tests of off-ice sprint and 3 hop jump to adequately assess skating ability. To improve on-ice skating performance and cornering ability, coaches should also focus on the development of horizontal power through specific off-ice training, although future research will determine whether off-ice improvements in horizontal power directly transfer to improvements in on-ice skating.

Macronutrient intake and whole body protein metabolism following resistance exercise.

UNLABELLED The provision of carbohydrate (CHO) supplements following resistance exercise attenuated muscle protein (PRO) degradation (Roy et al. J. Appl. Physiol. 82:1882-1888, 1997). The addition of PRO may have a synergistic effect upon whole body protein balance by increasing synthesis (Biolo et al. Am. J. Physiol. 273:E122-E129, 1997). PURPOSE To determine if the macronutrient composition of a postexercise beverage would alter muscle anabolism and/or catabolism following resistance exercise. METHODS We provided isoenergetic CHO (1 g x kg(-1)) and CHO/PRO/FAT supplements and placebo (PL) immediately (t = 0 h) and 1 h (t = + 1 h) following resistance exercise (9 exercises/3 sets/80% 1 RM) to 10 young, healthy, resistance-trained males. Whole body leucine turnover was determined from L-[1-13C]leucine kinetics at approximately 4 h postexercise. RESULTS No differences were observed for urinary 3-methylhistidine or urea nitrogen excretion between the trials. Leucine flux was significantly elevated at approximately 4 h postexercise for both CHO/PRO/FAT (177.59+/-12.68 micromol x kg(-1) x h(-1)) and CHO (156.18+/-7.77 micromol x kg(-1) x h(-1)) versus PL (126.32+/-10.51 micromol x kg(-1) x h(-1)) (P < 0.01). Whole body leucine oxidation was elevated at approximately 4 h for CHO/PRO/FAT (29.50+/-3.34 micromol x kg(-1) h(-1)) versus CHO (16.32+/-2.33 micromol x kg(-1) x h(-1)) (P < 0.01) and PL (21.29+/-2.54 micromol x kg(-1) x h(-1)) (P < 0.05). Nonoxidative leucine disposal (NOLD) was significantly elevated at approximately 4 h for both CHO/PRO/FAT (148.09+/-10.37 micromol x kg(-1) x h(-1)) and CHO (139.86+/-7.02 micromol x kg(-1) x h(-1)) versus PL (105.03+/-8.97 micromol x kg(-1) x h(-1)) (P < 0.01). CONCLUSIONS These results suggest that consumption of either CHO or CHO/PRO/FAT immediately and 1 h following a resistance training bout increased NOLD as compared with a placebo.

Physical activity prescription: a critical opportunity to address a modifiable risk factor for the prevention and management of chronic disease: a position statement by the Canadian Academy of Sport and Exercise Medicine

Non-communicable disease is a leading threat to global health. Physical inactivity is a large contributor to this problem; in fact, the WHO ranks it as the fourth leading risk factor for overall morbidity and mortality worldwide. In Canada, at least 4 of 5 adults do not meet the Canadian Physical Activity Guidelines of 150 min of moderate-to-vigorous physical activity per week. Physicians play an important role in the dissemination of physical activity (PA) recommendations to a broad segment of the population, as over 80% of Canadians visit their doctors every year and prefer to get health information directly from them. Unfortunately, most physicians do not regularly assess or prescribe PA as part of routine care, and even when discussed, few provide specific recommendations. PA prescription has the potential to be an important therapeutic agent for all ages in primary, secondary and tertiary prevention of chronic disease. Sport and exercise medicine (SEM) physicians are particularly well suited for this role and should collaborate with their primary care colleagues for optimal patient care. The purpose of this Canadian Academy and Sport and Exercise Medicine position statement is to provide an evidence-based, best practices summary to better equip SEM and primary care physicians to prescribe PA and exercise, specifically for the prevention and management of non-communicable disease. This will be achieved by addressing common questions and perceived barriers in the field. Author note This position statement has been endorsed by the following nine sport medicine societies: Australasian College of Sports and Exercise Physicians (ACSEP), American Medical Society for Sports Medicine (AMSSM), British Association of Sports and Exercise Medicine (BASEM), European College of Sport & Exercise Physicians (ECOSEP), Norsk forening for idrettsmedisin og fysisk aktivite (NIMF), South African Sports Medicine Association (SASMA), Schweizerische Gesellschaft für Sportmedizin/Swiss Society of Sports Medicine (SGSM/SSSM), Sport Doctors Australia (SDrA), Swedish Society of Exercise and Sports Medicine (SFAIM), and CASEM.

Health care provider confidence and exercise prescription practices of Exercise is Medicine Canada workshop attendees

The Exercise is Medicine Canada (EIMC) initiative promotes physical activity counselling and exercise prescription within health care. The purpose of this study was to evaluate perceptions and practices around physical activity counselling and exercise prescription in health care professionals before and after EIMC training. Prior to and directly following EIMC workshops, 209 participants (physicians (n = 113); allied health professionals (AHPs) (n = 54), including primarily nurses (n = 36) and others; and exercise professionals (EPs) (n = 23), including kinesiologists (n = 16), physiotherapists (n = 5), and personal trainers (n = 2)) from 7 provinces completed self-reflection questionnaires. Compared with AHPs, physicians saw more patients (78% > 15 patients/day vs 93% < 15 patients/day; p < 0.001) and reported lower frequencies of exercise counselling during routine client encounters (48% vs 72% in most sessions; p < 0.001). EPs had higher confidence providing physical activity information (92 ± 11%) compared with both physicians (52 ± 25%; p < 0.001) and AHPs (56 ± 24%; p < 0.001). Physicians indicated that they experienced greater difficulty including physical activity and exercise counselling into sessions (2.74 ± 0.71, out of 5) compared with AHPs (2.17 ± 0.94; p = 0.001) and EPs (1.43 ± 0.66; p < 0.001). Physicians rated the most impactful barriers to exercise prescription as lack of patient interest (2.77 ± 0.85 out of 4), resources (2.65 ± 0.82 out of 4), and time (2.62 ± 0.71 out of 4). The majority of physicians (85%) provided a written prescription for exercise in <10% of appointments. Following the workshop, 87% of physician attendees proposed at least one change to practice; 47% intended on changing their practice by prescribing exercise routinely, and 33% planned on increasing physical activity and exercise counselling, measured through open-ended responses.

What I always wanted to know about instability training

A very popular mode of training in recent years has been the use of instability devices and exercises to train the core musculature. Instability training is viewed by many as the most effective way to train the core; however, evidence on this topic paints a slightly different picture. An extensive review of the literature by Behm et al. 2010 (Appl. Physiol. Metab. Nutr. 35(1): 91-108) identified the fact that instability training can increase core muscle activation, but it may not be the best choice in all situations. Unstable training can reduce overall muscular power output, which may have important implications if the goal of a given training program is to maximize the output or physiological stress on a given muscle, as is the case in certain types of athletic training or in certain clinical exercise situations. Nevertheless, the balance of this evidence leads to the recommendations in the position stand (Behm et al. 2010, Appl. Physiol. Metab. Nutr. 35(1): 109-112) that instability training can play an important role as part of an overall periodized program for an athlete, as part of a rehabilitation program in recovery from injury, or as an interesting and novel training mode for the general population in pursuit of musculoskeletal health benefits who may not have access to or want to complete more intensive free-weight training programs. More research is needed to establish the effectiveness of instability training in preventing injury in sports, enhancing on-field sport performance, or for use in various clinical situations outside of rehabilitation for low back pain.

A pilot study: Validity and reliability of the CSEP−PATH PASB-Q and a new leisure time physical activity questionnaire to assess physical activity and sedentary behaviours

The purpose of this study was to evaluate the accuracy of 2 newly developed physical activity questionnaires: the Canadian Society for Exercise Physiology (CSEP) Physical Activity and Sedentary Behaviour Questionnaire (PASB-Q) and a newly modified Leisure-Time Physical Activity Questionnaire (mLTPA-Q). These questionnaires were compared with objective measurements of physical activity and fitness (accelerometry and physiological assessments) in 35 adults, before and after a week of daily living activity. Objectively measured moderate- to vigorous-intensity aerobic physical activity (MVPA) was moderately correlated with the PASB-Qs physical activity vital sign (PAVS) (r = 0.50, p = 0.004) and the mLTPA-Q (r = 0.56, p = 0.001). Bland-Altman plots suggest minimal bias from self-reported to objective measures of MVPA. The ability of PAVS to accurately distinguish who does and does not achieve Canadian physical activity guidelines was 83% and 60%, respectively, compared with 82% and 73% of the mLTPA-Q. Self-reported sedentary time was greatly underestimated in the PASB-Q compared with the objective measure (6.4 ± 3.5 vs 12.2 ± 1.2 h/day). The results of this study suggest the PASB-Q and mLTPA-Q are valid and reliable measures of adult physical activity and provide reasonable indication of those individuals who meet physical activity guidelines. Future questionnaire development should take into account the underestimation of time spent engaging in sedentary activities.

Physical Activity Prescription: A Critical Opportunity to Address a Modifiable Risk Factor for the Prevention and Management of Chronic Disease: A Position Statement by the Canadian Academy of Sport and Exercise Medicine.

Western University, London, Ontario, Canada Dip Sport Med (CASEM), Laval University, Ville de Québec, Quebec, Canada University of British Columbia, Vancouver, British Columbia, Canada Institut Universitaire de Cardiologie et de Pneumologie de Québec and Faculty of Pharmacy, Laval University, Québec, Canada Acadia University, Wolfville, Nova Scotia, Canada Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada Dip. Sport Med (CASEM), University of Ottawa, Ontario, Canada

Medical-Grade Physical Activity Monitoring for Measuring Step Count and Moderate-to-Vigorous Physical Activity: Validity and Reliability Study

Background The use of physical activity (PA) monitors is commonly associated with an increase in habitual PA level in healthy and clinical populations. The PiezoRx is a medical-grade PA monitor that uses adjustable step rate thresholds to estimate moderate-to-vigorous physical activity (MVPA) and is a valid indicator of free-living PA in adults. Laboratory validation of step count derived MVPA in adults is needed to justify the use of these monitors in clinical practice to track individuals’ progress toward meeting PA guidelines that are based on MVPA, not steps. Objective The objective of our study was to assess the validity and interinstrument reliability of the PiezoRx to derive step count and MVPA in a laboratory setting compared with criterion measures and other frequently used PA monitors in a diverse sample of adults. Methods The adult participants (n=43; 39.4 years, SD 15.2) wore an Omron HJ-320 pedometer, an ActiGraph GT3X accelerometer, and four PiezoRx monitors during a progressive treadmill protocol conducted for 6 minutes at speeds of 2.4, 3.2, 4.0, 5.6, 6.4, and 7.2 km/hour, respectively. The four PiezoRx monitors were set at different MVPA step rate thresholds (MPA in steps/minute/VPA in steps/minute) 100/120, 110/130, height adjusted, and height+fitness adjusted. Results The PiezoRx was more correlated (intraclass correlation, ICC=.97; P<.001) to manual step counting than the ActiGraph (ICC=.72; P<.001) and Omron (ICC=.62; P<.001). The PiezoRxs absolute percent error in measuring steps was 2.2% (ActiGraph=15.9%; Omron=15.0%). Compared with indirect calorimetry, the height-adjusted PiezoRx and ActiGraph were accurate measures of the time spent in MVPA (both ICC=.76; P<.001). Conclusions The PiezoRx PA monitor appears to be a valid and reliable measure of step count and MVPA in this diverse sample of adults. The device’s ability to measure MVPA may be improved when anthropometric differences are considered, performing at par or better than a research grade accelerometer.

Achieving Canadian physical activity guidelines is associated with better vascular function independent of aerobic fitness and sedentary time in older adults

Canadian physical activity guidelines recommend older adults accumulate 150 min of weekly moderate to vigorous physical activity (MVPA). Older adults who are insufficiently active may have reduced blood vessel health and an increased risk of cardiovascular disease. We tested this hypothesis in 11 older adults who did (7 female; age, 65 ± 5 years; MVPA, = 239 ± 81 min/week) and 10 older adults who did not (7 female; age, 68 ± 9 years; MVPA, 95 ± 33 min/week) meet MVPA guidelines. Flow-mediated dilation (FMD) in the brachial (BA) and popliteal (POP) arteries, as well as nitroglycerin-mediated dilation (NMD; endothelial-independent dilation) in the POP were assessed via ultrasonography. Aerobic fitness (peak oxygen uptake) was determined using a graded, maximal cycle ergometry test via indirect calorimetry. MVPA and sedentary time were assessed over 5 days using the PiezoRx and activPAL, respectively. There were no differences in peak oxygen uptake (26 ± 10 vs. 22 ± 10 mL O2/(kg·min); p = 0.26) or sedentary time (512 ± 64 vs. 517 ± 76 min/day; p = 0.87) between groups; however, those who achieved the MVPA guidelines had a higher BA-FMD (5.1% ± 1.3% vs. 3.6% ± 1.7%; p = 0.03), POP-FMD (2.6% ± 1.1% vs. 1.3% ± 0.8%; p = 0.006), and POP-NMD (5.1% ± 1.7% vs. 3.3% ± 2.1%; p = 0.04). In the pooled sample, MVPA was moderately correlated to both BA-FMD (r = 0.53; p = 0.01) and POP-NMD (r = 0.59; p = 0.005), and strongly correlated to POP-FMD (r = 0.85; p < 0.001). Collectively, our results provide supporting evidence that meeting MVPA guidelines is associated with better vascular function and may reduce the risk of developing cardiovascular disease in older adults. Furthermore, these data suggest that weekly MVPA time may have a greater impact on blood vessel function than aerobic fitness and weekly sedentary time.

BMI-specific waist circumference is better than skinfolds for health-risk determination in the general population

Distribution of fat is important when considering health risk; however, the value added from skinfold measurements (SKF) when using body mass index (BMI) refined by waist circumference (WC) is not well understood. The purpose of this study was to assess the utility of SKF compared with WC in determination of health risk in the general population. Data from the Canadian Health Measures Survey (cycles 1 and 2; N = 5217) were used. Health outcomes included directly measured blood pressure, cholesterol, glycated haemoglobin, lung function, self-reported health, and chronic conditions. Technical errors of measurements (TEM), sensitivity, and specificity analysis and linear regressions were conducted. Data indicated that TEM for SKF was above the acceptable 5% in most age and sex categories. Sensitivity and specificity of chronic conditions was not improved with the inclusion of SKF in models containing WC (in those aged 45-69 years) and SKF did not explain any additional variance in regression models containing WC. Health outcomes for those in the normal weight and overweight BMI category were significantly worse in those classified as high risk based on WC, whereas SKF did not consistently discriminate risk. In conclusion, evidence-based WC cut-points were shown to identify health risk, particularly in normal weight and overweight individuals. Thus, BMI refined by WC appears to be more appropriate than SKF for assessment of body composition when determining health risk in the general population.