Time filter

Source Type

Medicine, Qatar

Hamilton B.,Aspetar
Scandinavian Journal of Medicine and Science in Sports | Year: 2010

Vitamin D deficiency is an increasingly described phenomenon worldwide, with well-known impacts on calcium metabolism and bone health. Vitamin D has also been associated with chronic health problems such as bowel and colonic cancer, arthritis, diabetes and cardiovascular disease. In recent decades, there has been increased awareness of the impact of vitamin D on muscle morphology and function, but this is not well recognized in the Sports Medicine literature. In the early 20th century, athletes and coaches felt that ultraviolet rays had a positive impact on athletic performance, and increasingly, evidence is accumulating to support this view. Both cross-sectional and longitudinal studies allude to a functional role for vitamin D in muscle and more recently the discovery of the vitamin D receptor in muscle tissue provides a mechanistic understanding of the function of vitamin D within muscle. The identification of broad genomic and non-genomic roles for vitamin D within skeletal muscle has highlighted the potential impact vitamin D deficiency may have on both underperformance and the risk of injury in athletes. This review describes the current understanding of the role vitamin D plays within skeletal muscle tissue. © 2009 John Wiley & Sons A/S. Source

Owen A.L.,Rangers Football Club | Wong D.P.,The Hong Kong Institute of Education | Paul D.,Aspetar | Dellal A.,Olympic Lyon FC Soccer
Journal of Strength and Conditioning Research | Year: 2012

Effects of a periodized small-sided game training intervention on physical performance in elite professional soccer. J Strength Cond Res 26(10): 2748-2754, 2012-The present study examined the effects of periodized small-sided game (SSG) training intervention during a 4-week in-season break on the physical performance changes (i.e., speed, aerobic performance, and repeated sprint ability) within elite European soccer players. Fifteen, elite, male, professional players (age: 24.5 6 3.45 years; height: 181.1 ± 5.78 cm; body mass: 78.7 6 7.67 kg; VO2max: 54.88 ± 5.25 ml.kg21.min-1) from a Scottish Premier League team participated in 7 separate SSG sessions (3 vs. 3 plus goalkeepers) of which games lasted for a 3-minute duration for the selected number of games (ranged from 5 to 11) increasing over the intervention period. To examine the effects of the SSG intervention on physical performance changes, pre- and posttesting sessions took place over a 2-day period (day 1: anthropometry and repeated sprint ability [RSA] assessments; day 2: running economy [RE] and blood lactate assessments). Results show that the 4-week SSG training intervention induced significant improvement in RSA as indicated by faster 10-m sprint time (p < 0.05, small effect), total sprint time (p < 0.05, medium effect), and smaller percentage decrement score (p < 0.05, medium effect). Furthermore, the SSGs also led to an improvement in RE as indicated through significantly reduced VO2 and heart rate at running speed 9, 11, and 14 km.h-1 (all p's < 0.05, large effects). In conclusion, the present study demonstrates that implementing a periodized SSG training intervention during the 4-week in-season break is capable of improving elite-level soccer players' physical fitness characteristics. Being able to develop physical characteristics in conjunction to technical and tactical elements of the game, within a relatively short period, makes SSGs an appealing proposition for fitness coaches, players, and technical coaches alike. © 2012 National Strength and Conditioning Association. Source

Lane A.M.,University of Wolverhampton | Wilson M.,Aspetar
Journal of Science and Medicine in Sport | Year: 2011

Objectives The aim of this study was to investigate relationships between trait emotional intelligence and emotional state changes over the course of an ultra-endurance foot race covering a route of approximately 175 miles (282. km) and held in set stages over six days. Design A repeated measures field design that sought to maintain ecological validity was used. Trait emotional intelligence was defined as a relatively stable concept that should predict adaptive emotional states experienced over the duration of the race and therefore associate with pleasant emotions during a 6-stage endurance event. Method Thirty-four runners completed a self-report measure of trait emotional intelligence before the event started. Participants reported emotional states before and after each of the six races. Results Repeated measures ANOVA results showed significant variations in emotions over time and a main effect for trait emotional intelligence. Runners high in self-report trait emotional intelligence also reported higher pleasant and lower unpleasant emotions than runners low in trait emotional intelligence. Conclusions Findings lend support to the notion that trait emotional intelligence associates with adaptive psychological states, suggesting that it may be a key individual difference that explains why some athletes respond to repeated bouts of hard exercise better than others. Future research should test the effectiveness of interventions designed to enhance trait emotional intelligence and examine the attendant impact on emotional responses to intense exercise during multi-stage events. © 2011. Source

Hamilton B.,Aspetar
Asian Journal of Sports Medicine | Year: 2011

Vitamin D deficiency is a worldwide epidemic, with well known impacts on calcium metabolism and bone health, but increasingly recognized associations with chronic health problems such as bowel and colonic cancer, arthritis, diabetes and cardiovascular disease. In recent years in the Sports Medicine literature, there has been an increased focus on the potential impact that inadequate Vitamin D levels may have on athletic performance. In the early 20th Century, athletes and coaches felt that ultraviolet rays had a positive impact on athletic performance, and while remaining limited, evidence is accumulating to support this view. Muscle structure and function is recognised to play a key role in athletic performance, and both cross-sectional and longitudinal studies allude to a functional role for Vitamin D in muscle. The identification of the Vitamin D receptor in muscle tissue provides a direct pathway for Vitamin D to impact upon Skeletal Muscle structure and function. This review focuses on the current understanding of the action of Vitamin D within skeletal muscle tissue, and the potential impact on performance. © 2011 by Sports Medicine Research Center, Tehran University of Medical Sciences, All rights reserved. Source

Almudehki F.,Aspetar | Girard O.,Research and Education Center | Grantham J.,Research and Education Center | Racinais S.,Research and Education Center
Journal of Science and Medicine in Sport | Year: 2012

Objectives: To investigate the effect of hot exposure on the ability to perform intermittent cycling sprints. Design: Repeated measures. Methods: Ten male volunteers performed 35min of intermittent cycling comprising of 8 maximal 6-s sprints interspersed by 1min of passive recovery followed by 4min of constant-load pedaling (1Wkg -1 of body weight) on a cycle ergometer in control (24̊C, 24%rH) and hot (40̊C, 40%rH) environments. Results: Peak power output did not decrease during the exercise and was not dependent on the environmental temperature (average of 767 ± 120. W in control and 767 ± 119. W in hot, NS). Skin temperatures (e.g., chest: 36.8 ± 0.8 vs. 32.7 ± 0.6°C), heart rate (132 ± 13 vs. 118 ± 13. bpm) and rating of perceived exertion (13 ± 3 vs. 11 ± 3) were higher (all p < .05) in hot than control environment. However, EMG activity (RMS, vastus lateralis) and neuromuscular efficiency (power/RMS ratio) were similar at the two environmental conditions. Conclusions: Despite higher cardiovascular and perceptual strain in the hot trial, heat exposure did not alter neither peak power output nor related muscle activation and neuromuscular efficiency in the absence of hyperthermia (average core temperature of 37.6 ± 0.3°C in control vs. 37.7 ± 0.4°C in hot, NS). © 2011 Sports Medicine Australia. Source

Discover hidden collaborations