| Abstract | BACKGROUND: The effects of dietary factors such as carbohydrate on endurance running performance have been extensively studied under laboratory-based and simulated field conditions. Evidence from 'real-life' events, however, is poorly characterized. The purpose of this observational study was to examine the associations between pre-race and in-race nutrition tendencies and performance in a sample of novice marathoners. METHODS: Forty-six college students (36 women and 10 men) aged 21.3 ± 3.3 yrs recorded diet for 3-days prior to, the morning of, and during a 26.2-mile marathon. Anthropometric, physiological, and performance measurements were assessed prior to the marathon so the associations between diet and marathon time could be included as part of a stepwise regression model. RESULTS: Mean marathon time was 266 ± 42 minutes. A pre-marathon 2-mile time trial explained 73% of the variability in marathon time (adjusted R2 = 0.73, p < 0.001). Day before + morning of carbohydrate (DBMC) was the only other significant predictor of marathon time, explaining an additional 4% of the variability in marathon time (adjusted R2 = 0.77, p = 0.006). Other factors such as age, BMI, gender, day before + morning of energy, and in-race carbohydrate were not significant independent predictors of marathon time. CONCLUSIONS: In this sample of primarily novice marathoners, DBMC intake was associated with faster marathon time, independent of other known predictors. These results suggest that novice and recreational marathoners should consider consuming a moderate-to-high amount of carbohydrate in the 24-36 hours prior to a marathon. |
