Lower-limb joint kinetics in jump rope skills performed by competitive athletes

The purpose of this study was to characterise lower-limb joint kinetics during consecutive double unders and speed step sprints performed by competitive jump rope athletes, and to compare these measurements to running. Sixteen adolescent competitive jump rope athletes performed consecutive double under, speed step, and running trials while motion capture and ground reaction force data were collected. Lower-limb joint moments, power, and work were calculated using an inverse dynamics approach and discrete measurements were compared between skills. Peak ground reaction forces were similar between movements; however, knee and hip joint kinetics were distributed differently between double unders and speed step. In general, double unders were characterised by an increased reliance on knee joint kinetics, while speed step was characterised by an increased reliance on hip joint kinetics. Peak ankle moments were 9-20% greater in speed step when compared to double unders and running (p <= 0.050), and peak negative ankle power was 39-114% greater in double unders and speed step when compared to running (p <= 0.002). These findings may have important implications for injury risk and load management in jump rope athletes or other individuals that incorporate jump rope into their training programs.