Comparison of Different Timing Effect of Carbohydrate Intake Before Exercise on MFO And Fatmax in Endurance Runners

The aim of this study was to compare of different timing effect of carbohydrate intake before exercise on maximal fat oxidation (MFO) and Fatmax in endurance runners. Eight professional endurance runners (age 21.6±2.61 years, VO2max 63.0±8.7 ml.kg.min, body fat percentage 9.1±1.92, Background 7±3 years) participated as the subject in four separate trials. In the first session, the participants performed a graded exercise tests at 8 a.m. in fasted condition on treadmill to exhaustion in order to determine the amount of Fatmax and MFO. In the second, third and fourth session, with an interval of seven to ten days, participants in fasted condition, consumed 1 gr carbohydrate per kg body weight, with 500 ml water five minutes, one and three hours before the beginning of graded exercise tests. The amount of MFO and Fatmax were measured through indirect calorimetry method using the gas analysis system with aim of stoichiometric equation. The analysis of variance tests with repeated measures was used for data analysis. When carbohydrate is consumed five minutes and one hour prior to physical activity, MFO and Fatmax depict the lowest and highest decline respectively. MFO and Fatmax, in fasted condition, was significantly higher than the consumption of carbohydrate five minutes, one hour and three hours before the exercise (P