Comparison of spatiotemporal and angular parameters during shallow water walking in different immersion depths by older adults with and without Parkinson's disease

Background: People with Parkinson's Disease (PwPD) have motor symptoms that directly interfere on dry land walking performance. Despite the shallow water walking is a viable and beneficial physical intervention for PwPD, it lacks information on the comparison of the biomechanical responses of the shallow water walking by PwPD and age paired healthy individuals.

Research question: Are there differences in the spatiotemporal and angular responses of shallow water walking by older adults with and without Parkinson's disease?

Methods: In this cross-sectional study, ten older adults (9 men/1 women) with Parkinson disease (PwPD group) and ten older adults (3 men/7 women) without Parkinson's disease (Older group) walked in shallow water at self-selected comfortable speed on pool floor in the immersion depths of waist and xiphoid levels. The 2D kinematic data from the sagittal plane was collected to calculate the walking speed, stride length, stride frequency, duty factor, walk ratio, lower limb joints' range of motion and peak angular speed RESULTS: Both groups reduced similarly the walking speed with the immersion depth increase. The speed decrease was achieved by a reducing both the stride frequency and stride length only in the PwPD. The PwPD had lower contact phase than Older in the waist depth, probably due to the reduced risk of fall in water immersion and to attenuate drag force effects. The total range of joint motion was similar between groups, while the peak angular speed of ankle and knee reduced in the deeper depth in both groups.

Significance: The present findings can help professionals of aquatic rehabilitation to choose the best depth for exercise programs, according to the treatment objectives. To our knowledge, this was the first study that analyzed spatiotemporal and angular variables during shallow water walking of PwPD at different depths and compared them with older people without Parkinson's disease.