Jump Landings On Land And In Waist-Deep Water

Abstract

Current research on aquatic jump training has focused on performance benefits in younger, not older, participants. Aquatic jump training may be particularly beneficial for middle-age and older adults given its low impact nature and focus on power and stability, which are often compromised with aging. It is unclear if the same aquatic jumping benefits (e., reduced impact forces) observed in younger adults applies to middle-age adults. PURPOSE: To compare landing kinetics and dynamic stability between young and middle-age adults performing jumping movements on land and in water. METHODS: Ten young (age = 24 ± 2.6 yrs) and ten middle-age (age = 47 ± 3.0 yrs) adults performed three jump variations (countermovement jump, squat jump, and drop landing) on land and in waist-deep water. Dynamic stability was assessed during landing using a time to stabilization (TTS) paradigm. Kinetic measures included time to peak force, peak force, rate of force development (RFD), and impulse. Data were collected via a waterproof force platform positioned on an adjustable-depth pool floor. Data were analyzed using a 2 (environment) X 2 (age) X 3 (jump type) ANOVA. RESULTS: Regardless of age and jump type, TTS was greater (p = 0.02) on land (1.42 ± 0.12s) than in water (1.34 ± 0.13s). Peak force, RFD, and impulse followed this same trend and were greater on land than in water (p < 0.01). Time to peak force for the middle-age group (0.07 s) was lower (p = 0.001), while normalized peak force (4.4 BW) and RFD (74 BW/s) were greater (p < 0.05) than values for the young group (0.08 s, 3.8 BW, and 53 BW/s, respectively) regardless of environment or jump type. CONCLUSION: Regardless of age or jump type, TTS was lower in water suggesting greater dynamic stability in this environment. Additionally, participants displayed lower impact forces in water suggesting this environment might be safer than land when performing jump training. Across environments, middle-age participants landed with greater loading rates and peak forces when compared to the younger group.