Background/objectives: Orthostatic hypotension (OH) is a common condition among older adults that increases the risk of falls. The study objectives are to determine the influence of distinct environments (water vs. land) on OH and the consequent effects of walking in these environments in older adults. Additionally, we aimed to assess the differences in response between two groups: older adults with OH and those without OH.

Methods: A randomized crossover design was utilized including one session involving water walking and the other session involving land walking, with a 1- to 3-day washout period. Orthostatic hemodynamic measurements were obtained before, immediately after, and 2 hr after a 15-min walking session. Two subgroups were formed for analysis: participants with OH (n = 14, 81 ± 7 years) and participants without OH (n = 11, 84 ± 7 years).

Results: Compared with the land environment, an 86% reduction in the frequency of OH episodes was noted when the older adults were immersed in water. This reduction was accompanied by greater mean arterial pressure, while participants without OH showed no such changes. The frequency of OH episodes was similar when assessed immediately after emerging from the pool following water-based walking or after land-based walking. All participants exhibited elevated mean arterial pressure immediately after water-based walking, but not after land-based walking. Two hours after walking, all participants demonstrated similar mean arterial pressure and frequency of OH episodes, regardless of the environment.

Conclusions: Water immersion resulted in a substantial reduction in the frequency of OH episodes among older adults. Additionally, the frequency of OH episodes was not affected by prior walking exercise in either environment. Significance/Implication: These findings underscore the safety and potential advantages of water-based exercise for older adults dealing with OH.