27 The present study aimed to investigate the influence of timing of pre-exercise carbohydrate 28 feeding (Part A), and carbohydrate concentration (Part B), on short-duration high-intensity 29 exercise capacity. In Part A, seventeen males, and in Part B ten males, performed a peak 30 power output (PPO) test, two familiarisation trials at 90% of PPO, and 4 (for Part A) or 3 (for 31 Part B) experimental trials involving exercise capacity tests at 90% PPO. In Part A, the 4 trials 32 were conducted following ingestion of a 6.4% carbohydrate/electrolyte sports drink ingested 30 33 (C30) or 120 (C120) minutes before exercise, or a flavour-matched placebo administered either 34 30 (P30) or 120 (P120) minutes before exercise. In Part B, the 3 trials were performed 30 35 minutes after ingestion of 0%, 2% or 12% carbohydrate solutions. All trials were performed in a 36 double blind cross-over design following and overnight fast. Dietary intake and activity in the two 37 days before trials was recorded and replicated on each visit. Glucose, lactate, heart rate and 38 mood/arousal were recorded at intervals during the trials. In Part A, C30 produced the greatest 39 exercise capacity (mean±SD; 9.0±1.9 min, P<0.01) compared with all other trials (7.7±1.5 min 40 P30, 8.0±1.7 min P120, 7.9±1.9 min C120). In Part B, exercise capacity (min) following 41 ingestion of the 2% solution (9.2±2.1) compared with 0% (8.2±0.7) and 12% (8.0±1.3) solutions 42 approached significance (p=0.09). This study provides new evidence to suggest that timing of 43 carbohydrate intake is important in short duration high-intensity exercise tasks, but a 44 concentration effect requires further exploration. 45 46 47 48 The majority of studies examining the effects of carbohydrate feeding on exercise performance 49 and exercise capacity have focused on carbohydrate ingestion during prolonged exercise, or on 50 pre-exercise carbohydrate feeding in the few hours or minutes before prolonged endurance 51 activities (for reviews see Cermak & Van Loon, 2013; Temesi et al., 2011; Karelis et al., 2010; 52 Jeukendrup & Killer, 2010). There has been limited focus on carbohydrate feeding prior to short 53 duration (<10 min), high-intensity (>85% max), exercise tasks, presumably because it is 54 acknowledged that muscle glycogen depletion will not be limiting during exercise of this nature. 55 As a result, guidelines for pre-event fuelling focus on providing information about carbohydrate 56 intake before endurance exercise tasks lasting longer than 60 minutes (Burke et al., 2011). 57 Current guidelines specify that there is no requirement for ingestion of carbohydrate before 58 events lasting less than 45 minutes. Furthermore, it is recognized that ingestion of carbohydrate 59 in the immediate pre-exercise period (30-60 minutes before exercise) can reduce liver glucose 60 output, stimulate glucose uptake and oxidation and induce a rebound hypoglycaemia in 61 susceptible individuals (Williams and Lamb, 2008; Jeukendrup & Killer, 2010). Interestingly, 62 these known me...

Sweat losses in team sports can be significant due to repeated bursts of high-intensity activity, as well as the large body size of athletes, equipment and uniform requirements, and environmental heat stress often present during training and competition. In this paper we aimed to: (1) describe sweat losses and fluid balance changes reported in team sport athletes, (2) review the literature assessing the impact of hypohydration on cognitive, technical, and physical performance in sports-specific studies, (3) briefly review the potential mechanisms by which hypohydration may impact team sport performance, and (4) discuss considerations for future directions. Significant hypohydration (mean body mass loss (BML) >2%) has been reported most consistently in soccer. Although American Football, rugby, basketball, tennis, and ice hockey have reported high sweating rates, fluid balance disturbances have generally been mild (mean BML <2%), suggesting that drinking opportunities were sufficient for most athletes to offset significant fluid losses. The effect of hydration status on team sport performance has been studied mostly in soccer, basketball, cricket, and baseball, with mixed results. Hypohydration typically impaired performance at higher levels of BML (3–4%) and when the method of dehydration involved heat stress. Increased subjective ratings of fatigue and perceived exertion consistently accompanied hypohydration and could explain, in part, the performance impairments reported in some studies. More research is needed to develop valid, reliable, and sensitive sport-specific protocols and should be used in future studies to determine the effects of hypohydration and modifying factors (e.g., age, sex, athlete caliber) on team sport performance.

These results show that a GI pill ingested immediately prior to physical activity cannot be used to measure core body temperature accurately in all individuals during the following 8 h when cool fluids are regularly ingested. This makes GI temperature measurement unsuitable for workers who respond to emergency deployments when regular fluid consumption is recommended operational practice.

MFO and FATMAX vary significantly between athletes participating in different sports but also in the same sport. Although variance in MFO can be explained to some extent by body composition and fitness status, more than 50% of the variance is not explained by these variables and remains unaccounted for.