Objectives: Poor balance is one of risk factors of falling, a cause of injury and even death in elderly. The aim of this study was to evaluate the effect of a water exercise program on static and dynamic balance in elder women.

Methods & Materials: Thirty participants aged 55-70 years completed an exercise program (60 min, 3 days and 6 weeks), in 2 groups, exercise and control, voluntarily. Static and dynamic balances were measured before and after exercise program in both groups. Postural sway parameters, including mean displacement of center of pressure and velocity of center of pressure in Medio-Lateral (ML) and Anterio-Posterior (AP) directions, in single stance position, as a measure of static balance and functional reach test, functional reach right test and functional reach left test, as dynamic measure of balance was considered. T test for deepened groups was used for evaluation of changes within groups, and T test for independent groups was used for between groups' changes at threshold of 0.05 After 6 weeks.

Results: Significant changes were observed in results of Functional Reach Test (FRT), Functional Reach Left Test (FRLT) after exercise program, also in average displacement of cop and velocity of cop in ML direction. Between groups significant differences were observed in results of average cop displacement and velocity of displacement, FRT and FRLT.

Conclusion: These results suggest that challenging the physiological systems involved in balance control, in water, while on the non stable support surface, improved both static and dynamic balance and probably might decrease the risk of falling.

Objectives The purpose of this study was to investigate the effect of deep aquatic exercises on balance among elderly men. 
Methods & Materials Thirty elderly men voluntarily participated in this experiment. Subjects were randomly divided into two equal groups including experimental and control groups. The experimental group participated in a deep aquatic exercise program that consisted of 60-minutes sessions three times a week for eight weeks, while the control group was not into any exercise. Postural stability (static balance) was assessed before and after the program as pre-test and post-test by Biodex Balance System (BBS) respectively. Independent sample t-test and paired sample t-test (P≤0.05) were performed on outcome variables.
Results The results of the comparison between the two groups of 15 individuals in terms of demographic and anthropometric features[experimental group with mean age of (65.50±3.481), height (168.10±5.215), weight (70.865±7.775) and body mass index (24.781±2.483) and the control group with an average age of (66.50±3.232), height (169.20±6.314), weight (71.322±8.531) and body mass index (24.982±3.535) were divided], the two groups showed no difference in results is homogeneity. The findings of the study showed that aquatic exercises program has significant effect on the static balance (P≤0.05). The results indicated significant differences between the subjects of experimental and control groups after the exercise program, and also paired sample t-test showed significant differences between pre and post-tests in experimental group while no differences observed in control group. 
Conclusion According to this study, doing the deep-aquatic exercises is effective on improving the static balance of old people and reducing their risk of falling.