Effect of Ramadan fasting: Association with time of day on time-motion, technical aspect and psychophysiological response to simulated karate competition in young amateur competitors

International audienceRamadan is characterized by daily abstinence from food and fluid intake from dawn to sunset. The understanding of the Ramadan effects on the diurnal variations of athletic performance is crucial for practitioners, coach and researchers to prepare sport events and optimize performance. The aim of the present study was to reveal the effect of Ramadan on the performance aspect, heart rate and rating of perceived exertion during a karate match. In a randomized counterbalanced, 2 x 2 cross-over order, 22 male and female amateur karate athletes (age = 16.8 years, body mass = 59.1 kg, height = 168.3 cm) participated in simulated karate match at 8-10 a.m. and 5-7 p.m. on three different occasions 1 week before Ramadan, the second week of Ramadan (during Ramadan), and 2 weeks after Ramadan. Performance aspects were analyzed, and heart rate and rating of perceived exertion were assessed before and immediately after the match at each visit. Our results demonstrated that Ramadan adversely affected time-motion variables (fighting time and preparatory time) and heart rate during simulated karate match (p < 0.05, all). However, heart rate pic response to karate match was higher during Ramadan when compared with before Ramadan and after Ramadan. However, rating of perceived exertion results did not show any variation during Ramadan phases. Concerning the interaction of Ramadan and time of day, fighting time and stoppage time were higher in the evening and in the morning before Ramadan and the inverse during Ramadan, respectively (p < 0.05). In conclusion, Ramadan altered the diurnal variation of performance aspect, in terms of fighting time and stoppage time, during simulated karate match