Self-report Internal Load Measures Of Readiness, Fatigue, Sleep, And Stress In Women’s Collegiate Volleyball

PURPOSE: External loads, such as jumping and landing frequencies, have been previously quantified and analyzed in women’s collegiate volleyball, yet internal loads are not as well understood. Internal load measures, such as sleep quality, fatigue, and stress may influence a volleyball athlete’s performance and injury risk. Thus, the purpose of this study was to track and quantify internal load measures in collegiate women’s volleyball. METHODS: Twenty-one, Division-1 collegiate female volleyball players (20.5 ± 1.4 years, 179.9 ± 7.5 cm, 72.3 ± 8.2 kg). All participants completed daily wellness questionnaires that tracked self-perceived levels of readiness, sleep quality, fatigue, and stress over the course of an entire season. Injuries were tracked and defined as any neuromusculoskeletal condition that resulted in >1 day of lost participation. Average readiness, sleep quality, fatigue, and stress scores were calculated across the season for all participants. Sub-analyses included a paired t-test comparing internal load variables between times of injury (participation days lost) and times of health (no days lost) and an independent t-test comparing uninjured participants internal load averages to injured participant internal load averages prior to the date of injury (α = 0.05). RESULTS: Compliance on the daily wellness surveys over the course of the season was 84.2%. On a 100-point scale, average readiness scores were 92.3 ± 9.8, and on a -5 to +5 scale: sleep quality was +2.95 ± 1.59, fatigue was +2.69 ± 1.81, and stress was +2.42 ± 1.96. Analyzing the injured athletes (n = 9), there was a significant difference in readiness score between injured (69.2 ± 24.7) and non-injured periods (88.5 ± 13.1, p = 0.04), but not sleep, fatigue, or stress scores (p > 0.05). There were no significant differences in any of the internal load variables when comparing the full season data of non-injured athletes to pre-injury data from the injured athletes (p > 0.05). CONCLUSIONS: Readiness, sleep quality, fatigue, and stress were generally positive throughout the course of a women’s collegiate volleyball season. Injured athletes did not show decrements in sleep, fatigue, or stress prior to injury or during the portion of the season in which they were injured.