The Effect Of Ad Libitum Intake Of Different Commercial Beverages And Snack Foods Following Exercise-induced Fluid Loss.

Abstract

PURPOSE: This study compared the effects of ad libitum consumption of different beverages and foods on fluid restoration and nutrient consumption following exercise. METHODS: Ten endurance trained males (VO2max, 62.95±7.20 ml/kg/min) performed four trials employing a randomised, crossover design. Following 60 minutes of standardised exercise (matched for energy expenditure and fluid loss) participants consumed either water (W1 and W2), a sports drink (Powerade (P)) or a milk-based liquid meal supplement (Sustagen Sport (SS)). Additionally, participants had access to snack foods at two time points within the first two hours of recovery. All beverages and food were consumed ad libitum. Total nutrient intake, urine volume, USG, body weight as well as subjective measures of gastrointestinal tolerance and thirst were obtained hourly. Plasma osmolality was measured pre, post, one and four hours after exercise. Results: Total fluid volume ingested from food and beverages in W1 (2.28±0.42 L) and P (2.82±0.80 L) trials was significantly greater than the SS (1.94±0.54 L) trial. No difference was observed between W2 (2.21±0.62 L) and SS. Total urine output was not different between trials (W1 644±202 mL, W2 602±352 mL, P 879±751 mL, SS 466±129 mL). Total energy intake was higher on the P (9695±1974 kJ) and SS (10577±2210 kJ) compared to both water trials (W1 = 7826±888 kJ, W2 = 7578±1112 kJ). CONCLUSION: Beverages with different nutrient profiles appear equally effective at replacing exercise induced fluid losses when consumed ad libitum with food. Therefore, choosing a post-exercise recovery beverage should consider hydration properties in the context of an individual’s post-exercise energy requirements and overall dietary goals.