The effect of the Ramadan fast on physical performance and dietary habits in adolescent soccer players.

The purpose of this study was to examine the effect of the Ramadan fast on performance capacities, dietary habits, and the daily behavioral patterns in adolescent (14-16-year-old) soccer players. Nineteen male players performed a series of fitness tests before and at the end of Ramadan fast. Caloric intake, physical activity pattern and sleep habits were evaluated during the week before the Ramadan fast and during the last week of the Ramadan fast. The fast resulted in a significant reduction in aerobic capacity [3,000 m run time (mean +/- SD): 812.8 +/- 73.3 s vs. 819.9 +/- 73.4 s, P < 0.001], speed endurance (Sum 6 x 40 m run time: 46.36 +/- 1.36 s vs. 46.73 +/- 1.31 s, P < 0.001, and performance decrement: 9.0 +/- 1.5% vs. 9.5 +/- 1.7%, P < 0.05), and jumping performance (44.8 +/- 4.5 cm vs. 44.0 +/- 4.5 cm, P < 0.05), but had no significant effect on sprint performance (7.38 +/- 0.25 s vs. 7.40 +/- 0.26 s, P = 0.20) or agility (4 x 10 m shuttle run time: 9.53 +/- 0.35 s vs. 9.55 +/- 0.37 s, P = 0.26). Daily intense physical activity was significantly reduced during Ramadan (6.4 +/- 0.2 h/week vs. 4.5 +/- 0.1 h/week, P < 0.005). There were no significant differences in total caloric intake (3,012 +/- 412 kcal/day vs. 3240 +/- 348 kcal/day, P = 0.39) or total daily sleeping hours (8.6 +/- 0.7 h/day vs. 8.6 +/- 0.5 h/day, P = 0.80) between Ramadan and a regular month. The results indicate that Ramadan fasting can lead to a significant decrease in athletic performance capacities. The decrease in performance does not necessarily relate to changes in caloric intake and sleeping hours during the fast.