In this study, we examined the effects of acute ingestion of a herbal drink (H) or a coloured water placebo (P) on physiological responses and performance during cycling exercise. Eight healthy and trained male young cyclists (age: 16.0±0.5years) exercised on a cycle ergometer at 72.0±0.8% of the maximal oxygen consumption (VO(2max)) until exhaustion in a room maintained at 23.9±0.2 °C and 64.2±1.6% relative humidity on two occasions, 1-week apart. During each exercise bout, subjects received 3ml.kg(-1) body weight of H or P every 20 minutes in a double-blind randomised study design. There was no significant difference between H and P trials in the total work time to exhaustion (84.5±5.1 and 82.3±5.6 min respectively). Changes in heart rate, oxygen consumption, plasma glucose concentrations, plasma lactate concentrations, rectal temperature, respiratory exchange ratio and energy expenditure were similar with both type of drinks. Loss of plasma volume was also similar with both drinks. Herbal drink elicited similar physiological responses, thermoregularity responses and exercise performances during endurance cycling when compared to the placebo ingestion. Thus, it can be concluded that the ingredient in the herbal drink did not provide any added advantage to cycling endurance performance.
Keywords: Herbal drink; cycling performance; cyclist; physiological responses; thermoregularity responses.