Physiological effects of a low intensity chair-based exercise program for the elderly
Eight sedentary elderly subjects (X̅ age = 83.4yr), including two males and six females, were evaluated to determine the effects of a low intensity, chair-based exercise program on selected physiological parameters. Exercise sessions were held 3 alternate days per week, 45 minutes per session, for 8 weeks. Subjects were exercise tested before and after training using a modification of the Smith and Gilligan chair step test; this is a multi-level graded exercise test suitable for very old subjects with aerobic exercise capacities of approximately 2-4 METs. Upon completion of training, group data analyses showed no significant adaptations in resting heart rate or blood pressure, exercise heart rate or blood pressure, peak exercise performance, nor for subject rating of perceived exertion at a fixed exercise intensity. A significant increase (p < 0.05) was observed post-training in the immediate post-exercise blood lactic acid response. Separating subjects (n=4) into high (91% attendance) and moderate (49% attendance) compliers, statistically significant differences were found for training related changes in several physiological parameters. Between-group analysis also showed significant changes (p < 0.05) in the chair exercise performance time. Post-training, the high compliers improved their total exercise tolerance (time) by 33%, whereas the moderate compliers exercise time was 22% less as compared to pre-training. A significant difference (p < 0.05) was also observed between groups in their perception of effort at a fixed-load in the exercise test. After training, the high compliers judged their effort to be 12% less at a fixed load in the chair exercise test, while the moderate compliers showed no significant changes (p < 0.05). Blood lactic acid responses were significantly higher (p < 0.05) after training for the high compliance group but no such change was found in the HLa response of the moderate compliers. There were no significant changes in resting or exercise heart rate and blood pressure responses in either the high or moderate compliance groups. The results of this study suggest that physiological adaptations do not occur in old individuals in response to a low intensity exercise program. Given these preliminary findings, further investigations are indicated to determine the effects of increased frequency and duration of physical activity programs on additional physiological parameters.