The influence of self-reported total sleep time and sleep quality on physical performance in junior tennis players

Studies have shown the importance of sleep on tennis skill execution; however, its influence on physical performance metrics is unclear. This study aimed to examine the extent to which sleep duration and sleep quality metrics influence physical performance metrics in junior tennis players. Thirty-six junior tennis players from Australia and Germany completed the Consensus Sleep Diary over seven nights. A novel total sleep score based on current National Sleep Foundation recommendations was generated (calculated as the percentage of the average standardised sleep metrics), for each player. Players physical performance was measured using a comprehensive tennis-specific testing battery. This included sit and reach test for flexibility, counter movement jump and overhead medicine ball throw for power, 5-, 10- and 20-metre sprints for speed, tennis agility test for agility and reaction time, grip strength for strength, repeat sprint ability for anaerobic capacity and the Hit and Turn Tennis Test for aerobic capacity. Teenage (14 to 17 years of age) players reported significantly lower sleep duration (471 ± 116 min versus 543 ± 72 min; p <0.001, d = 0.83) and sleep efficiency (90% ± 11% versus 94 % ± 5%; p = 0.011, d = 0.49) metrics than school-aged players. Players with higher self-reported sleep quality had slower reaction times during a tennis agility test (r = 0.604, p = 0.011). However, players who reported feeling more rested and refreshed had faster reaction times during a tennis agility test (r = -0.579, p = 0.020). No other significant associations were present between self-reported sleep metrics and physical performance metrics. Nevertheless, feeling well-rested and refreshed, one of the primary outcomes of sleep, improves reaction time during a tennis-specific agility test. However, physical performance metrics are not significantly influenced by small variations in recommended sleep duration and sleep quality ranges.