Browsing Faculty of Education, Health and Wellbeing by Publisher "Journal of Sports Science and Medicine"
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Chronic eccentric exercise and antioxidant supplementation: effects on lipid profile and insulin sensitivityEccentric exercise has been shown to exert beneficial effects in both lipid profile and insulin sensitivity. Antioxidant supplementation during chronic exercise is controversial as it may prevent the physiological training-induced adaptations. The aim of this study was to investigate: 1) the minimum duration of the eccentric exercise training required before changes on metabolic parameters are observed and 2) whether antioxidant supplementation during training would interfere with these adaptations. Sixteen young healthy men were randomized into the Vit group (1 g of vitamin C and 400 IU vitamin E daily) and the placebo (PL) group. Subjects received the supplementation for 9 weeks. During weeks 5-9 all participants went through an eccentric exercise training protocol consisting of two exercise sessions (5 sets of 15 eccentric maximal voluntary contractions) per week. Plasma triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL), low density lipoprotein (LDL), apolipoproteins (Apo A1, Apo B and Lpa) and insulin sensitivity (HOMA) were assessed before the supplementation (week 0), at weeks 5, 6, 7, 8 and 9. TG, TC and LDL were significantly lower compared to pre supplementation at both weeks 8 and 9 (P<0.05) in both groups. HDL was significantly elevated after 4 weeks of training (p < 0.005) in both groups. There was no effect of the antioxidant supplementation in any of the variables. There was no effect of either the training or the supplementation protocol in apolipoproteins levels and insulin sensitivity. A minimum duration of 3 weeks of eccentric exercise training is required before beneficial effects in lipid profile can be observed in healthy young men. Concomitant antioxidant supplementation does not interfere with the training-induced adaptations.
Soccer referee decision-making: ‘Shall I blow the whistle?'Evidence points to the existence of a home advantage effect in soccer with referees giving more decisions to the home team being a plausible explanation for this effect. The purpose of the present study was to use qualitative methods to explore the factors that influence experienced referees when making decisions. Five experienced referees volunteered to participate in semi-structured interviews of 30-40 minutes duration. Examples of questions/probes included ‘Are there times when it is difficult to make a decision on whether there was a foul or not? When? Why?’ and ‘Do you worry about making the wrong / unpopular decision? What affect does this have on you?’ Content analysis identified 13 inter-related themes that describe four higher-order themes. The themes ‘accuracy-error’, ‘regulations’, and ‘professionalism’ form a higher-order theme labeled ‘ideal-decision making’. The themes ‘opinion’, ‘concentration’, and ‘control’ represent a higher-order theme labeled ‘individual factors’; ‘experience’, ‘personality’, and ‘personal life’ represent a higher-order factor labeled ‘experience factors’, and crowd factors, player reaction, environmental factors, and crowd interaction represent a higher-order factor labeled ‘situational factors’. Findings from the present study offer some insight into difficulties and coping strategies used by referees to perform consistently in professional soccer. Future research could use quantitative methods to test the relative contribution of themes identified above to the decisionmaking process in referees. At an applied level, practitioners should develop strategies that accelerate the process of learning to cope with performance-related stressors such as the crowd noise.
The impact of moderate and high intensity total body fatigue on passing accuracy in expert and novice basketball playersDespite the acknowledged importance of fatigue on performance in sport, ecologically sound studies investigating fatigue and its effects on sport-specific skills are surprisingly rare. The aim of this study was to investigate the effect of moderate and high intensity total body fatigue on passing accuracy in expert and novice basketball players. Ten novice basketball players (age: 23.30 ± 1.05 yrs) and ten expert basketball players (age: 22.50 ± 0.41 yrs) volunteered to participate in the study. Both groups performed the modified AAHPERD Basketball Passing Test under three different testing conditions: rest, moderate intensity and high intensity total body fatigue. Fatigue intensity was established using a percentage of the maximal number of squat thrusts performed by the participant in one minute. ANOVA with repeated measures revealed a significant (F 2,36 = 5.252, p = 0.01) level of fatigue by level of skill interaction. On examination of the mean scores it is clear that following high intensity total body fatigue there is a significant detriment in the passing performance of both novice and expert basketball players when compared to their resting scores. Fundamentally however, the detrimental impact of fatigue on passing performance is not as steep in the expert players compared to the novice players. The results suggest that expert or skilled players are better able to cope with both moderate and high intensity fatigue conditions and maintain a higher level of performance when compared to novice players. The findings of this research therefore, suggest the need for trainers and conditioning coaches in basketball to include moderate, but particularly high intensity exercise into their skills sessions. This specific training may enable players at all levels of the game to better cope with the demands of the game on court and maintain a higher standard of play.
The Influence of a Pacesetter on Psychological Responses and Pacing Behavior during a 1600 m RunThis study compared the effects of following a pacer versus following a self-paced plan on psychological responses and pacing behavior in well-trained distance runners. Pacing in the present study was individually tailored where each participant developed a personal strategy to ensure their goal time was achieved. We expected that following a pacer would associate with goal achievement, higher pre-run confidence, positive emotions and lower perceived exertion during performance. In a mixed-design repeated-measures study, nineteen well-trained runners completed two 1600m running time trials. Ten runners had a pacer (paced group) who supported their individual pacing strategy, and nine participants self-paced running alone (control group). Both groups could check pace using their wrist watch. In contrast to our expectation, results indicated that the paced group reported higher pre-run anxiety with no significant differences in finish time, goal confidence, goal difficulty, perceived exertion, and self-rated performance between groups. We suggest that following a pacer is a skill that requires learning. Following a personalised pacer might associate with higher anxiety due to uncertainty in being able to keep up with the pacer and public visibility of dropping behind, something that is not so observable in a self-paced run completed alone. Future research should investigate mechanisms associated with effective pacing.