Impact of COVID-19 lockdown on endurance capacity of elite handball players

BACKGROUND: The lockdown due to the Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 has far-reaching consequences for professional sports in Germany. The aim of the present study was to investigate the impact of the eight-week lockdown on endurance capacity of elite male handball players. METHODS: Ten male athletes (192 +/- 8 cm and 96 +/- 6 kg) from the first German handball league participated in the study. The effects of training on shuttle run tests between period 1 (P1: pre-season to mid-season) and period 2 (P2: mid-season to time after lockdown) were compared. The maximum oxygen uptake (VO2max) was assessed using an incremental exercise test (IET) (July 2019 and May 2020). RESULTS: During the COVID-19 lockdown, the athletes completed an instructed home-based strength and endurance program (52/48). The training effects were found to be reduced after the 8-weeks of COVID-19 lockdown (period 2) as compared to period 1 (mean difference 249 +/- 248 m, P=0.005). There was no significant difference in the running distance (2358 +/- 430 m vs. 2400 +/- 362 m, respectively, P=0.70) after the lockdown as compared to the pre-seasonal performance. VO2max (46.6 +/- 5.1 vs. 49.4 +/- 7.0 mL/kg/min, respectively, P=0.12) and the power output (3.13 +/- 0.36 vs. 3.13 +/- 0.43 W/kg, respectively, P=1.0) also did not differ between pre-season and after COVID-19 lockdown. CONCLUSIONS: The COVID-19 lockdown led to a reduction in endurance capacity of elite handball players without team training, despite a home-based strength and endurance program. Supervision of individual home-based training is highly recommended to avoid inadequate implementation of the training.