Age-Related Changes in Postural Sway Are Not Consistent Between Land and Aquatic Environments

Area of Science:

• Biomechanics
• Human Physiology
• Gerontology

Background:

• Understanding age-related balance changes is crucial for developing effective therapies.
• No prior studies have compared aquatic postural sway across age groups with varying water depths and perturbations.

Purpose of the Study:

• To compare the effects of water depth and jet intensity on postural sway in older and younger adults.
• To investigate age-related differences in postural control within aquatic environments.

Main Methods:

• Participants: 16 older adults (62.8 ± 9.56 yrs) and 15 younger adults (22.5 ± 1.85 yrs).
• Procedure: Quiet standing for 90 seconds on land and in water at various depths and jet intensities.
• Measurement: Center of pressure (CoP) sway recorded using a force platform.

Main Results:

• Postural sway (CoP range and area) was significantly greater in aquatic conditions compared to land (P = .04–.001).
• Chest-deep water (8.51 ± 2.97 cm²) and 60% jet intensity (71.4 ± 31.2 cm²) markedly increased sway area.
• Significant age-by-environment interactions (P = .03–.001) revealed older adults swayed less than younger adults in hip-deep water and at high jet intensities.

Conclusions:

• Chest-deep water immersion with high jet intensities maximizes CoP sway due to buoyancy and perturbation.
• Reduced sway in older adults may indicate a compensatory strategy to enhance stability by limiting degrees of freedom.