Effects of a 90‐Min Nap on Time‐Motion Metrics and Psychophysiological Responses During Small‐Sided Games in Professional Soccer Players

This study investigated the impact of a 90-min nap (N90) on time-motion metrics and psychophysiological responses during small-sided games (SSGs) in soccer players. In a within-subjects counterbalanced design, 15 professional male soccer players (mean ± SD; age: 22.4 ± 1.2 years; stature: 178 ± 9 cm; body mass: 70.1 ± 4.0 kg; estimated VO_2max: 55.9 ± 2.8 mL·min^-1·kg^-1) completed two SSGs sessions under N90 and no-nap (N0) conditions. N90 was monitored using a Fitbit Charge 6 wristband. Daytime sleepiness was assessed pre- and post-nap. Mood states, the wellness status (Hooper index), and cognitive performance (Go/NoGo task) were evaluated before each SSGs session. Time-motion metrics, obtained via the FieldWiz GPS system, along with exercise heart rate (HR), were continuously monitored throughout the SSGs. Blood lactate concentration ([La]) and ratings of perceived exertion (RPE) were assessed post-SSGs. Compared to N0, the N90 condition resulted in a significantly greater total distance covered during SSGs (p = 0.002, Cohen's |d| = 0.96), lower presession resting HR (p < 0.001, |d| = 1.33), and reduced relative exercise HR (p = 0.03, |d| = 0.33). Additionally, post-SSGs [La] and RPE were lower following N90 (p = 0.015, |d| = 0.71 and p = 0.001, |d| = 1.03 respectively). The N90 also led to higher vigor scores (p = 0.003, |d| = 1.01), lower Hooper index values (p = 0.02, |d| = 0.59), and faster reaction time (p = 0.02, |r| = 0.60) than N0. A 90-min nap before SSGs training increased total distance covered, reduced perceived fatigue, and enhanced mood, wellness, and cognitive alertness. These findings support implementing a 90-min nap as a practical ergogenic aid to optimize recovery status, performance, cognitive alertness and overall well-being in professional soccer players.