Música Auto-Seleccionada y Rendimiento Anaeróbico en Jugadores de Futsal Durante el Ramadán (MUSIC-RAST)

This study was designed to examine whether standardized high-tempo music used during warm-up affects anaerobic power differently during and after Ramadan fasting in trained male soccer players.

Sixteen male soccer players completed four experimental sessions in a 2 × 2 within-participant repeated-measures design combining assessment period (during Ramadan vs. approximately two weeks after Ramadan) and warm-up condition (music vs. no music). Because the music intervention was delivered collectively through loudspeakers, all participants completed the same condition within a given session, and the condition order was therefore not randomized or counterbalanced at the individual level. During Ramadan, the no-music condition was performed first, followed by the music condition; this order was reversed during the post-Ramadan assessment period. Consecutive sessions were separated by at least 48 h. Each participant served as his own control.

Before the anaerobic performance test, participants completed a modified FIFA 11+ warm-up. In the music condition, a standardized high-tempo music playlist (120-140 bpm) was delivered through loudspeakers during the warm-up, whereas the same warm-up was performed without music in the no-music condition. Anaerobic performance was subsequently assessed using the Running-Based Anaerobic Sprint Test (RAST), consisting of six maximal 35-m sprints. The primary outcomes were peak power, mean power, relative peak power, and relative mean power.

To minimize nutrition-related variability between the two assessment periods, individualized dietary plans based on body mass were prepared for all participants by a dietitian on the research team. The plans provided approximately 40 kcal/kg/day of energy, 6 g/kg/day of carbohydrate, and 1.6 g/kg/day of protein, with the remaining energy derived from fat. During Ramadan, dietary intake was distributed across Suhoor, Iftar, and one nighttime snack, and participants abstained from food and fluids between dawn and sunset. During the post-Ramadan period, the same energy and macronutrient targets were maintained but distributed according to the participants' habitual daytime eating patterns.

Dietary adherence was assessed in both assessment periods using three-day food records covering the two days preceding testing and the test day. Energy, carbohydrate, protein, and fat intake, as well as meal timing, were recorded. To standardize hydration, participants were instructed to consume approximately 3.5 L of total fluids per day. During Ramadan, fluid intake was restricted to the period between Iftar and Suhoor, whereas during the post-Ramadan period, fluid intake was distributed throughout the day. Fluid intake was monitored using the food records; hydration status was not objectively assessed using biomarkers.