The aim of this study was to assess the effectiveness of a 24-week exercise protocol carried out in geothermal spring water to improve overall physical function and muscle mass in a group of healthy elderly subjects. A further aim was to compare this water-based protocol with a land-based protocol and a control group. For this purpose, 59 subjects were recruited and randomly allocated to three groups: aquatic group (AG), land group (LG), and control group (CG). AG and LG followed a 6-month, twice-weekly, multimodality exercise intervention. AG underwent the protocol in hot-spring water (36°C) while LG did it in a land-based environment. After the intervention, knee-extension strength was maintained in AG and LG. The 8-foot up-and-go test showed a reduction in both exercise groups (AG -19.3%, P < 0.05; LG -12.6%, P < 0.05), with a significantly greater decrease in AG. The back-scratch test revealed an improvement only in AG (25.8%; P < 0.05), while the sit-and-reach test improved in all groups. Finally, AG reduced fat mass by 4% (P < 0.05), and dominant forearm fat decreased by 9.2% (P < 0.05). In addition, calf muscle density increased by 1.8% (P < 0.05). In summary, both water- and land-based activities were beneficial in maintaining strength and in improving lower-body flexibility. Aquatic exercise appeared a better activity to improve dynamic balance. Thermal swimming pools and the use of rating of perceived exertion as a method of exercise monitoring should be considered potentially useful tools to enhance physical performance and body composition in healthy elderly.
Keywords: aging; multimodality exercise; muscle mass; performance.