Effect of Knee Compression on Kinetic Variables During Vertical Jumps

The purpose of this study was to determine how knee compression affected kinetic variables during vertical jumps. Ten healthy males, age 20s, performed a single maximum vertical jump and a ten-consecutive vertical jump trial without knee compression (control condition) and with knee compression. The collected data of ground reaction force were used to analyse the vertical jump height (VJH), peak active force (PAF), decay rate (DR), peak passive force (PPF), loading rate (LR), and the coefficient of variation (CV). During a maximum vertical jump, knee compression increased the magnitudes of DR, PAF, and VJH by 19.8%, 3.41%, and 4.87%, respectively, compared to those under a control condition. During ten consecutive vertical jumps, PAF and VJH showed statistically significant difference according to the repetition count. Also, the mean and CV of PAF, DR, LR, and VJH over consecutive jumps were higher in magnitude under knee compression condition than under the control condition.