The Effect of Underwater Treadmill Training on Static Balance, Dynamic Balance, and Cognitive Ability of Sedentary Elderly Women

The aging process is associated with gradual physiological changes in body systems. Identifying problems and issues of the elderly to improve their level of health is essential. Physical activity is an effective way to prevent, delay, or treat aging consequences. The underwater treadmill is one of the most recommended devices for the elderly and people who suffer from joint and muscle pain. One of the main and essential advantages of using an underwater treadmill is that it removes all the limitations people face in aerobic sports and treadmills and the possibility of sports activities. All people of different ages and different levels of physical fitness can use this treadmill. One of the limitations in these sports is the pressure exerted that can lead to muscle cramps and injuries and exacerbate joint wear in certain people, such as those with chronic joint disease, people with obesity, and the elderly, which prevents them from doing so do sports activities. This study aimed to investigate the effect of underwater treadmill exercise on static balance, dynamic balance, and cognitive ability of inactive elderly women.

The research is a quasi–experimental study with a pretest–posttest design and a control group. Out of the elderly women referred to Hijia Sports Club in Arak City, Iran, 30 elderly women over 60 years old were randomly selected and divided into two experimental and control groups (each group with 15 people). The sample size of the present study was determined by Cohen's table of sample size in experimental studies, considering the effect size of 0.7, test power of 0.91, and the significance level of 0.05. The inclusion criteria included their interest, liking, and non–involvement in regular exercise programs. The personal information questionnaire was also used to control other inclusion criteria such as independence in daily activities and no vision problems, history of falls in the last year, joint dislocation or chronic arthritis, and dizziness; otherwise, they were excluded from the study. The experimental group performed running on an underwater treadmill for 8 weeks, three sessions per week (24 sessions in total), and each session lasted 30 minutes. The training intensity was determined for 10 minutes with 40%–45% and 20 minutes with 55%–65% of the maximum heart rate reserve. All sessions began with a short warm–up, including light aerobic activity and dynamic, static stretching, and ended with a cool–down. It is noteworthy that the control group performed daily activities during the intervention and did not have any other effective and regular sports activities. Changes in static and dynamic balance and cognitive ability before and after the training period were measured by the Modified Stork test (Stork, 1976), Dynamic Balance Performance test (Timed Up and Go test) (Mahtisa, 1985), and Mini–Mental State Examination (MMSE) (Folstein et al., 1975). The collected data were classified and described by calculating the mean and standard deviation and drawing a table. Analysis of covariance was used to analyze the data and test the research hypotheses. Data analysis was performed in SPSS software version 22. A significance level of 0.05 was considered in all analyzes.

The results showed that after the exercise intervention with an underwater treadmill, a significant difference was found between the experimental group with the control regarding the mean scores of static balance (p<0.001), dynamic balance (p<0.001), and cognitive ability (p<0.001), so that the static balance score, dynamic balance, and cognitive ability was higher in the experimental group than the control group. Eta squared showed that 62% of the increase in static balance, 71% of the increase in dynamic balance, and 70% of the increase in cognitive ability in the inactive elderly woman was due to the effect of training with an underwater treadmill.

According to the results, 8 weeks of underwater treadmill training effectively improves static balance, dynamic balance, and cognitive ability of inactive elderly women.