Comparison of Propulsive Power During Loaded Countermovement Jumps Performed in Water versus Land in College Aged Males

Clint R. Nardoni, Utah State University

Abstract

As use of an aquatic environment increases as a training and rehabilitative tool, the purpose of this study was to assess peak propulsive power in loaded countermovement jumps (CMJ) in water and compare them to loaded CMJ on land. 20 college aged (24.6±3.6 years) recreationally active males performed 4 randomized countermovement jumps on a force plate with increasing loads (bodyweight [BW], BW+10%, BW+20%, BW+30%) in two environments: immersed in water at the xiphoid process and on land. Peak power (PP) and mean power (MP) normalized to apparent mass were assessed for all jumps. A 2 (environment) by 4 (load) repeated measures ANOVA was used to determine main effects and the interaction. PP was greater in the water for all loading conditions compared to land (13.1±3.4, 12.3±3.6, 10.4±3.4, 9.9±3.1 kW vs 5.8±1.4, 5.7±1.4, 5.8±1.4, 5.9±1.4 kW) for the BW, BW+10%, BW+20% and BW+30% conditions, respectively. The same trend and magnitude differences were identified for MP (5.5±1.7, 5.2±2, 4.4±1.5, 4.1±1.6 kW vs 2.6±0.8, 2.4±0.8, 2.5±0.8, 2.5±0.7 kW) for water vs land, respectively. The trend for decrease in PP and MP in water was significant while there were no significant trends for decreases in PP and MP on land. These results suggest loading BW on land in the range of 10-30% essentially has no detrimental impact on PP and MP measures yet creates a significant reduction when performed in water. Potential decreases in force production and/or movement velocities during takeoff may account for these observed differences due to environment. Further research could identify these differences and provide valuable insights for strength and conditioning professionals to use an aquatic environment to complement traditional land-based training.