Athletic Performance and Serial Weight Changes During 12- and 24-Hour Ultra-Marathons
- 1 March 2008
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in Clinical Journal of Sport Medicine
- Vol. 18 (2), 155-158
- https://doi.org/10.1097/jsm.0b013e31815cdd37
Abstract
The principal objective of this study was to evaluate serial weight changes in athletes during 12- and 24-hour ultra-marathons and to correlate these changes with athletic performance, namely the distance covered. This was a prospective study. The 2003 Soochow University international ultra-marathon. Fifty-two race participants. 12- or 24-hour ultra-marathon. Body weight changes were measured before, at 4-hour intervals during, and immediately after the 12- and 24-hour races. Significant overall decreases in body weight were apparent at the conclusion of both races. The mean relative body weight change after the 12-hour race was -2.89 +/- 1.56%, ranging from 0 to 6.5%. The mean relative body weight change after the 24-hour race was -5.05 +/- 2.28%, ranging from -0.77% to -11.40%. Of runners in the 24-hour race, 26% lost greater than 7% of baseline body weight during the race. During both the 12- and 24-hour races, the greatest weight change (decrease) occurred during the first 4 hours. Weight remained relatively stable after 8 hours, although a further decrease was apparent between 16 and 20 hours in the 24-hour participants. Weight change had no bearing on performance in the 12-hour race, whereas weight loss was positively associated with performance in the 24-hour race. Our findings demonstrate that the majority of weight decrease/dehydration in both the 12- and 24-hour races occurred during the first 8 hours. Hence, to maintain body weight, fluid intake should be optimized in the first 8 hours for both 12- and 24-hour runners and in 16 to 20 hours for 24-hour marathon runners.Keywords
This publication has 13 references indexed in Scilit:
- Exercise-Associated Hyponatremia: Role of CytokinesAmerican Journal Of Medicine, 2006
- Hyponatremia among Runners in the Boston MarathonThe New England Journal of Medicine, 2005
- Fluid Replacement during Marathon RunningClinical Journal of Sport Medicine, 2003
- Weight Changes, Sodium Levels, and Performance in the South African Ironman TriathlonClinical Journal of Sport Medicine, 2002
- Hyponatremia Associated With Exercise: Risk Factors and PathogenesisExercise and Sport Sciences Reviews, 2001
- Physiological determinants of endurance exercise performanceJournal of Science and Medicine in Sport, 1999
- Hyponatremia in ultradistance triathletesMedicine & Science in Sports & Exercise, 1999
- Nutritional and Fluid Intake in a 100-km UltramarathonInternational Journal of Sport Nutrition, 1998
- Effects of Bodyweight Reduction on Sports PerformanceSports Medicine, 1994
- Medical and physiological considerations in triathlonsThe American Journal of Sports Medicine, 1987