CLINICS 2011;66(9):1513-1518 for effective area, the higher values for anterior-posterior standard deviation and range demonstrate that the women with higher fat mass scores oscillate their center-of-foot pressure more than the women with lower fat mass scores as predicted by our hypothesis. The observed differences were mainly in anterior-posterior direction, which was expected, due to the loss of ankle flexibility in elderly individuals. Furthermore, the lack of ankle flexibility influences anterior-posterior stability more than does lateral stability.32 Postural control differences in tandem positions were not observed. Considering that only 34 and 35 individuals (for the right and left conditions, respectively) successfully completed 60 seconds in this stance, the exclusion of subjects with poor performance could have influenced the final results. These trials were excluded when the hand support or foot adjustment added noise to the signal for the center-of-foot displacement. However, women with poor performance in tandem stances were not considered for analysis if these signals had been excluded, and only those with less body sway remained in the analysis. This decision could have influenced the power of the study to distinguish an association between adiposity and body sway. A study carried out in Sa˜o Paulo, Brazil, determined that postural control in quiet standing may not influence the quality or pattern of movement during functional activity;33 thus, tandem positions were expected to show greater differences than quiet stance trials. The correlations of fat mass and waist circumference with unilateral stance behavior can be explained by the smaller range of the stability limit previously documented in obese individuals.9 These correlations and the differences in certain stabilometric variables between the High and Low Fat Mass Groups attest to the relationship between adiposity and instability in the present elderly sample. Thus, it can be speculated that a higher quantity of fat mass may influence the localization and displacement of the center-of-foot pressure, altering stabilometric variables and causing the subject to make a greater number of hand and foot contacts to avoid falls during unilateral stance. After the sixth decade, it is well established that there is a reduction in total body mass, which is primarily influenced by the decrease in bone and muscle mass.34 Furthermore, aging is associated with fat redistribution; visceral fat increases, whereas subcutaneous fat in other regions of the body (abdomen, thigh, calves) decreases.22 These changes may disturb postural control. Health professionals should be concerned with overweight and obese elderly individuals. Without specific intervention, aging will increase body fat, decreasing the level of total physical activity even further and increasing the accumula- tion of adipose tissue. In accordance with the reported results, this higher amount of fat mass can increase instability and disturb postural control in the elderly, which could lead to a greater number of falls. A focus on the prevention and treatment of obesity in elderly subjects delays the risk of metabolic complications, reduces the risk of falls and, consequently, enhances the quality of life of the elderly population. Because obesity occurs when energy intake consistently exceeds energy expenditure, interventions must emphasize nutrition reeducation and promote an adequate level of physical activity and a healthy lifestyle, as recom- mended by a multi-professional team, including physicians, physical therapists, psychologists, physical educators and 1517 Adiposity and Balance Control in the Elderly Mainenti MRM et al. dietitians. Regular evaluation of adiposity levels in elderly individuals should be adopted using such simple but reliable techniques as bioelectrical impedance and waist circumfer- ence measurements. Furthermore, balance and mobility tests must also be performed using stabilometry or other methods used in clinical practice, such as the Berg balance scale and timed up-and-go test. It is important to emphasize that the results of the present study are limited to the selected population, which consists of a sample that was readily recruited from female participants in a university program for the elderly. Although the use of bioelectrical impedance to measure body composition is a limitation of this study, given that there are more accurate methods for assessing body fat levels, bioelectrical impedance is widely used in clinics and health promotion centers. CONCLUSIONS This study shows that there is an association between body adiposity and postural balance control in elderly women. 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