The sweat sodium loss of participants in WCS (Table 3) is similar to values reported by other groups studying elite athletes [15, 28]. While there was no difference in sodium loss with the different

drinks, sodium balance was almost unchanged in the INW group compared to C and G conditions. This was a result of the INW drink being designed for full sodium replacement. Sodium intake is essential for the absorption and retention of fluid during exercise [27]. Results from hydration testing in other sports have shown elite athletes have difficulty replacing sodium lost during training using fluid replacement drinks [19, 29]. These finding, coupled with our results from CCS, can be explained in part by the ad libitum fluid consumption study protocol. This indicates athletes may have difficulty self-regulating learn more their hydration requirements particularly in cold conditions, as it is easy to Lazertinib cell line become caught-up in the focus and intensity of training and/or competition. This further supports the need for individual, sport specific

or relative fixed volume fluid replacement recommendations. Blood MK-8776 solubility dmso glucose carbohydrates intake Examination of the energy demands of Laser sailing by Castagna and Brisswalter [11] revealed aerobic metabolism is the main energy source used by elite sailors to fulfill muscle energy demands. As such, blood glucose levels in CCS were trending towards a decrease over time (p = 0.074), despite the supply of exogenous carbohydrates in the G

and IN groups; although, the average carbohydrate intake in these groups was only 61 g and 42 g respectively. Interestingly, the blood glucose concentration Avelestat (AZD9668) of the C group was stable through the 2.5 h training session despite consuming no exogenous carbohydrates (Figure 1D). In comparison, trained cyclists working at 74% VO2max in laboratory conditions experienced a significant decrease in blood glucose after 90 minutes of cycling [30]. Examination of substrate metabolism during 60 minutes of cycling at 70% VO2max at 0°C revealed almost 60% of energy expenditure was from carbohydrate metabolism [31]. This level was maintained regardless of infused non-esterified fatty acids, suggesting that carbohydrates are a preferred source of energy in cold conditions as fatty acid metabolism has been found to increase based on substrate availability in temperature environments [32]. While the intensity of Laser sailing in conditions similar to CCS reached approximately 65% VO2max [11], this difference in intensity may have been enough to prevent deleterious changes in blood glucose in the C condition. In WCS, blood glucose levels were surprisingly unchanged between the drink conditions (Figure 2D). Although a main effect for time was observed (p = 0.