Changes in vertical jump performance and body composition before and after COVID-19 lockdown

This study aimed to determine the effects of a 16-week COVID-19 lockdown on body 5 composition and vertical jump performance. Thirteen martial artists participated in this study. 6 Participants were tested at: 1) pre-lockdown (pre), 2) post-lockdown (post), 3) two-weeks-ptaost-7 lockdown (post+2), and 4) four-weeks-post-lockdown (post+4). Repeated-measures-ANOVAs 8 were conducted with post-hoc analyzes. Differences were observed in vertical jump height 9 (VJH) (10.33%), peak velocity (PV) (3.10%), reactive-strength-index-modified (RSImod) 10 (13.8%), and peak-propulsive-power (PPP) (6.00%) from pre-to-post. There as an increase from 11 post-to-post+2 in VJ (13.06%), PV (4.12%), RSImod (14.0%), and PPP (4.66%). There was an 12 increase from post to post+2 in VJH (10.8%), PV (3.1%), RSImod (14.0%), and PPP (3.0%). Fat 13 mass (FM) and BF% increased from pre to post (13% and 11%, respectively) and decreased from 14 post to post+4 (8% and 11%, respectively); fat-free mass (FFM) decreased from pre-to-post 15 (11%) and decreased from post-to-post+4 (8%). There were moderate associations (rmc= 0.42-16 0.47) between FFM and VJH, FMM and PPP, FFM and PV, BF% and PV, and FM and PV.