An investigation into sleep patterns and the effect of time of day on performance in youth swimmers

The purpose of this study was to investigate sleep patterns in competitive youth swimmers and to establish any time-of-day effect on physiological and psychological variables linked to swimming performance. Twelve swimmers (14.8 ± 2.1 years) underwent physiological and psychological tests in morning and evening and completed sleep diaries over a 2-week period. There was a non-significant effect between morning and evening swimming performance for 800 m (p = 0.068) and 50 m (p = 0.306). Handgrip strength was significantly greater in evening (p = 0.007), back and leg strength were significantly greater in morning (p = 0.013). There was no time-of-day effect for jump height (p = 0.756). The profile of mood states indicated significantly higher anger (p = 0.012) and vigour (p = 0.000) in the morning. Swimming performance was not significantly affected by time of day; however, physiological variables showed varied results. Multiple factors could be influencing results including training time and mood state so should be monitored closely by coaches

Land based resistance training and youth swimming performance

Resistance training has been shown to have both performance-enhancing and injury reducing benefits in youth athletes. The benefits are somewhat overlooked by many swimming coaches, therefore the effects of a structured resistance training programme in highly trained youth swimmers was investigated. Nine competitive youth swimmers (age: 13 ± 1.1 years) underwent a 7 week dry-land resistance training programme. Swimming performance and other relevant physiological parameters were measured pre- and post-training. There was a small non-significant improvement in swimming performance following the 7 week training programme (100m freestyle; p > 0.05, ES = 0.26). Countermovement jump height (p < 0.05, ES = -1.26), back and leg strength (p < 0.05, ES = -1.85) and number of push ups completed in 60 s (p < 0.05, ES = -1.86) all significantly improved. Although the resistance training programme did not significantly improve swimming performance, other physiological parameters, important for success in the pool, did significantly improve. It may be that an adaptation period is needed so the swimmers can learn to efficiently apply their increased force in the water

An overview of the effect of probiotics and exercise on mood and associated health conditions

The present paper provides a review of the current knowledge relating to the health benefits of probiotics, specially focused on the effects they may have together with physical exercise on mood disorders and related chronic medical conditions. With both these conditions being a substantial contributor to the global disease burden any alternative therapy must be considered. Probiotics influence the gut microbiota through a complex network of events which can influence mechanisms leading to development of mood disorders such as depression and anxiety. Similarly, through a complex interaction between psychological and neurobiological mechanisms, exercise has been found to play a key role in mood enhancement

The influence of serial carbohydrate mouth rinsing on power output during a cycle sprint

The objective of the study was to investigate the influence of serial administration of a carbohydrate (CHO) mouth rinse on performance, metabolic and perceptual responses during a cycle sprint. Twelve physically active males (mean (± SD) age: 23.1 (3.0) years, height: 1.83 (0.07) m, body mass (BM): 86.3 (13.5) kg) completed the following mouth rinse trials in a randomized, counterbalanced, double-blind fashion; 1. 8 x 5 second rinses with a 25 ml CHO (6% w/v maltodextrin) solution, 2. 8 x 5 second rinses with a 25 ml placebo (PLA) solution. Following mouth rinse administration, participants completed a 30 second sprint on a cycle ergometer against a 0.075 g·kg-1 BM resistance. Eight participants achieved a greater peak power output (PPO) in the CHO trial, resulting in a significantly greater PPO compared with PLA (13.51 ± 2.19 vs. 13.20 ± 2. 14 W·kg-1, p < 0.05). Magnitude inference analysis reported a likely benefit (81% likelihood) of the CHO mouth rinse on PPO. In the CHO trial, mean power output (MPO) showed a trend for being greater in the first 5 seconds of the sprint and lower for the remainder of the sprint compared with the PLA trial (p > 0.05). No significant between-trials difference was reported for fatigue index, perceived exertion, arousal and nausea levels, or blood lactate and glucose concentrations. Serial administration of a CHO mouth rinse may significantly improve PPO during a cycle sprint. This improvement appears confined to the first 5 seconds of the sprint, and may come at a greater relative cost for the remainder of the sprint

The effect of prior upper body exercise on subsequent wingate performance

It has been reported previously that the upper body musculature is continually active during high intensity cycle ergometry. The aim of this study was to examine the effects of prior upper body exercise on subsequent Wingate (WAnT) performance. Eleven recreationally active males (20.8 ± 2.2 yrs; 77.7 ± 12.0 kg;  1.79 ± 0.04 m) completed two trials in a randomised order. In one trial participants completed 2 × 30 s WAnT tests (WAnT1 and WAnT2) with a 6 min recovery period; in the other trial, this protocol was preceded with 4 sets of biceps curls to induce localised arm fatigue. Prior upper body exercise was found to have a statistically significant detrimental effect on peak power output (PPO) during WAnT1 (P < 0.05) but no effect was observed for mean power output (MPO) (P > 0.05). Handgrip (HG) strength was also found to be significantly lower following the upper body exercise. These results demonstrate that the upper body  is meaningfully involved in the generation of leg power during intense cycling

Investigation of critical slowing down in a bistable S-SEED

A simulation of S-SEED switching based upon experimental data is developed that includes the effect of critical slowing down. The simulation's accuracy is demonstrated by close agreement with the results from experimental S-SEED switching. The simulation is subsequently used to understand how the phenomenon of critical slowing down applies to switching of an S-SEED and how the effect on photonic analog-to-digital (A/D) converter performance may be minimized.B. A. Clare, K. A. Corbett, K. J. Grant, P. B. Atanackovic, W. Marwood and J. Munc

Anthropole-ogy: The (Re)creation of Female Bodies Through Pole-dancing

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Weekly vitamin D₃ supplementation improves aerobic performance in combat sport athletes

Vitamin D3 supplementation can affect the strength and power of an athlete, however the effect on endurance performance remains unclear. Twenty-seven recreational male combat athletes with at least 12 months experience within combat sports were recruited (age: 24 ± 4 years, stature: 176 ± 6 cm, weight: 77 ± 14 kg). Participants completed baseline testing for blood haemoglobin and haematocrit, upper and lower body VO2peak and upper and lower body Wingate. Following testing participants were stratified to 50000IU (D1), 80000IU (D2) or 110000IU (D3) of vitamin D3 per week. They then completed a 6-week placebo period followed by a 6-week supplementation period. Retesting was carried out after the placebo and supplementation period. There was a significant effect for time for haemoglobin and haematocrit, upper and lower body VO2peak and upper body Wingate power (p<0.01) but no effect for dose of vitamin D given. Performance data was normalised to vitamin D intake and there was a moderate effect size between D1 and D2 for lower body VO2peak (d=0.6), upper body VO2peak (d=0.13) and upper body average power (d=0.75), with a large effect size between D1 and D2 for haemoglobin (d=1.19), haematocrit (d=0.93) and upper body peak power (d=0.95). There was a large effect size for D1 compared to D3 for all variables (d>0.8). Therefore, there is no additional benefit to increasing dose above 500000IU vitamin D per week. Given the endurance adaptations from vitamin D supplementation and the importance of endurance for combat performance, recreational combat athletes should supplement at 50000IU per week for six weeks

Women’s activewear trends and drivers: a systematic review

Purpose The activewear industry would benefit from an evidence-based understanding of how activewear is incorporated into women’s lives and their changing participation in physical activity. Activewear brands may be missing the trend of women moving from organised sport to non-organised and individualised sport and recreation. The purpose of this paper is to explore the degree to which academic and industry research understood patterns and influences on female’s activewear consumption and identified what significant gaps are evident in understanding the drivers and industry trends that pertain to female consumers of activewear. Design/methodology/approach The systematic literature review sought academic and industry research papers. Articles were selected if they included female participants; and/or addressed consumer related information; and focussed on active wear. Article findings were thematically analysed. Findings Most literature exploring activewear consumption fails to take gender into consideration or explore unique female consumer profiles. Females are bringing activewear into other parts of their wardrobe and place more value on fashion, even for sports attire. Research identified the need for activewear brands to consider lifestyle, emotional and personality elements of consumer behaviour. However a specific focus on women’s branding was absent. Women’s age and generation influenced their activewear consumption. Although some industry reports discussed the shift in use of activewear, no studies explored the impact of the critical shift in women’s physical activity patterns on the activewear industry. Originality/value This review identifies the gap in knowledge regarding women’s activewear consumption patterns and needs, and the importance of reflecting the changes in female physical activity participation. It also links marketing and design of women’s activewear to the needs of female consumers based on their actual patterns and trends in physical activity. The findings are relevant to activewear researchers, brands, marketers and producers