['The present study aimed to investigate the concomitant effects of Ramadan intermittent fast (RIF) and muscle fatigue on neuromuscular performances and reaction times in young trained athletes.', 'Eight karate players (17.2\u2009±\u20090.5\xa0years) were tested on three sessions: during a control period (S1: one week before Ramadan), and during the first (S2) and the fourth week of RIF (S3). Dietary intake and anthropometric measurements were assessed before each session. During each test session, participants performed maximal voluntary isometric contractions (MVC) and a submaximal contraction at 75\xa0% MVC until exhaustion (T lim ) of the right elbow flexors. Surface electromyography was recorded from biceps brachii muscle during MVC and T lim . Simple (SRT) and choice (CRT) reaction times were evaluated at rest and just after T lim in a random order.', 'The total daily energy (S2: +19.5\xa0%, p\u2009<\u20090.05; S3: +27.4\xa0%, p\u2009<\u20090.01) and water (S2: +26.8\xa0%, p\u2009<\u20090.01; S3: +23.2\xa0%, p\u2009<\u20090.05) intake were significantly increased during RIF. However, neither body mass nor body mass index was altered by RIF (F (2,14)\u2009=\u20090.80, p\u2009=\u20090.47 and F (2,14)\u2009=\u20090.78, p\u2009=\u20090.48, respectively). In addition, T lim (F (2,14)\u2009=\u20092.53, p\u2009=\u20090.12), MVC (F (2,14)\u2009=\u20090.51, p\u2009=\u20090.61) and associated electrical activity (F (2,14)\u2009=\u20090.13, p\u2009=\u20090.88) as well as neuromuscular efficiency (F (2,14)\u2009=\u20090.27, p\u2009=\u20090.76) were maintained during RIF. Moreover, neither SRT nor CRT was affected by RIF (F (2,14)\u2009=\u20091.82, p\u2009=\u20090.19 and F (2,14)\u2009=\u20090.26, p\u2009=\u20090.78, respectively) or neuromuscular fatigue (F (1,7)\u2009=\u20090.0002, p\u2009=\u20090.98 and F (1,7)\u2009=\u20093.78, p\u2009=\u20090.09, respectively).'] Does ramadan fasting adversely affect neuromuscular performances and reaction times in trained karate athletes?