Jump-Rope Training: Improved 3-km Time-Trial Performance in Endurance Runners via Enhanced Lower-Limb Reactivity and Foot-Arch Stiffness

Context: Plyometric training promotes a highly effective neuromuscular stimulus to improve running performance. Jumping rope (JR) involves mainly foot muscles and joints, due to the quick rebounds, and it might be considered a type of plyometric training for improving power and stiffness, some of the key factors for endurance-running performance. Purpose: To determine the effectiveness of JR during the warm-up routine of amateur endurance runners on jumping performance, reactivity, arch stiffness, and 3-km time-trial performance. Methods: Athletes were randomly assigned to an experimental (n = 51) or control (n = 45) group. Those from the control group were asked to maintain their training routines, while athletes from the experimental group had to modify their warm-up routines, including JR (2-4 sessions/wk, with a total time of 10-20 min/wk) for 10 weeks. Physical tests were performed before (pretest) and after (posttest) the intervention period and included jumping performance (countermovement-jump, squat-jump. and drop-jump tests). foot-arch stiffness, and 3-km time-trial performance. Reactive strength index (RSI) was calculated from a 30-cm drop jump. Results: The 2 x 2 analysis of variance showed significant pre-post differences in all dependent variables (P < .001) for the experimental group. No significant changes were reported in the control group (all P >= .05). Pearson correlation analysis revealed a significant relationship between Delta 3-km time trial and Delta RSI (r= -.481; P < .001) and Delta Stiffness (r= -.336; P < .01). The linear-regression analysis showed that Delta 3-km time trial was associated with Delta RSI and Delta Stiffness (R-2 = .394; P < .001). Conclusions: Compared with a control warm-up routine prior to endurance-running training, 10 weeks (2-4 times/wk) of JR training, in place of 5 minutes of regular warm-up activities, was effective in improving 3-km time-trial performance, jumping ability, RSI, and arch stiffness in amateur endurance runners. Improvements in RSI and arch stiffness were associated with improvements in 3-km time-trial performance.