Of key interest is the effect of sports drinks on exercise performance. The inclusion of CHO beverages has been shown to improve exercise performance and time to fatigue during relatively short laboratory [18–20] and field based assessments . More recently, studies have demonstrated
an effect of multiple transportable carbohydrates on sustained time trial performance Selleck EPZ5676 [22, 23] and power output [22, 24]. However, this is not supported elsewhere , especially when commercially available carbohydrate beverages have been used . With recent public interest in the accuracy of marketing claims, and whether commercially available sports drinks are indeed beneficial for performance [27, 28], Selleckchem PRIMA-1MET we were invited to undertake an independent assessment of a commercial maltodextrin/ fructose beverage (MD + F: Energy Source™, High 5 Ltd.) on total and exogenous carbohydrate oxidation, and fluid delivery in comparison to a maltodextrin only beverage (MD) and placebo (P). A further aim was to assess the influence of the three beverages on cycling performance following a period of sustained steady state exercise. It was hypothesised that the MD + F commercial formula would lead to greater exogenous oxidation and fluid delivery rates, resulting in a specific performance gains. Materials and methods Participants Fourteen club level male cyclists
were recruited for participation following power calculation assessment (G*Power3, Dusseldorf ). All participants had an endurance training MDV3100 cost background of at least two years, and did not suffer from diabetes or have known dysglycemia. Before undertaking the study, participants were required to provide written informed consent and satisfactorily complete a health screen questionnaire. Additionally, participants were Rucaparib concentration excluded if consuming other nutritional supplements. Ethical approval for the study was provided by the University of Hertfordshire Life and Medical Sciences Ethics Committee. Procedures Preliminary testing At least one week prior to experimental trials, participants completed an incremental exercise test to volitional exhaustion for assessment of maximal power output (Wmax) and maximal
oxygen consumption (VO2max). All testing was undertaken in the Human Physiology Laboratory, Division of Sport, Health and Exercise, University of Hertfordshire. Upon reporting to the laboratory, the participants’ nude body mass (Seca, model 780, Hamburg, Germany) and height were recorded. Following this, maximal tests were performed on a Computrainer (RaceMate Inc, Seattle, USA) and related Coaching Software program (Comp CS, RaceMate Inc, Seattle, USA). The Computrainer was pre-calibrated and standardised to the body mass and cycle of the participant. Following a 10 minute standardised warm-up at 100 W, an incremental step protocol was then undertaken, with power output progressing by 30 W each 3 minutes until volitional exhaustion.