Drinking behaviors of elite male runners during marathon competition

OBJECTIVE To describe the drinking behaviors of elite male marathon runners during major city marathons. DESIGN Retrospective analysis of drinking behaviors. SETTING Institutional. PARTICIPANTS Ten (9 winners and 1 second position) male marathon runners during 13 major city marathons. MAIN OUTCOME MEASURES Total drinking durations and fluid intake rates during major city marathons. RESULTS The ambient conditions during the 13 studied marathon races were 15.3°C ± 8.6°C and 59% ± 17% relative humidity; average marathon competition time was 02:06:31 ± 00:01:08 (hours:minutes:seconds). Total drinking duration during these races was 25.5 ± 15.0 seconds (range, 1.6-50.7 seconds) equating to an extrapolated fluid intake rate of 0.55 ± 0.34 L/h (range, 0.03-1.09 L/h). No significant correlations were found between total drink duration, fluid intake (rate and total), running speed, and ambient temperature. Estimated body mass (BM) loss based on calculated sweat rates and rates of fluid ingestion was 8.8% ± 2.1% (range, 6.6%-11.7%). Measurements of the winner in the 2009 Dubai marathon revealed a BM loss of 9.8%. CONCLUSIONS The most successful runners, during major city marathons, drink fluids ad libitum for less than approximately 60 seconds at an extrapolated fluid ingestion rate of 0.55 ± 0.34 L/h and comparable to the current American College of Sports Medicine's recommendations of 0.4-0.8 L/h. Nevertheless, these elite runners do not seem to maintain their BM within current recommended ranges of 2%-3%.