Exercise performance in those having Parkinson's disease and healthy normals

Objective: This study assessed and compared the cardiopulmonary function of individuals with Parkinson's disease (PD) with that of healthy normals (HN) in order to provide health professionals with more thorough information about the problems associated with PD. Methods: 20 men (PD = 13, HN = 7; mean age 64 and 64, respectively) and 23 women (PD = 7, HN = 16; mean age 65 and 66, respectively) were recruited from the Houston metropolitan area. Maximal oxygen consumption (V̇O(2max), mL · kg^-1 · min^-1) and time to maximal exercise in minutes (time(max)) were measured. Exercise was performed on a stationary bicycle using an incremental exercise protocol. Because the assumption of homogeneity of variance was not met for the dependent variable V̇O(2max), in women, the nonparametric Wilcoxon-Mann-Whitney-U analysis was used (alpha ≤ 0.025). All other group comparisons were analyzed using an independent t-test (alpha ≤ 0.025). Results: For men and women, there were no significant differences in V̇O(2max) between those having PD and the HN (men: PD = 23.52 vs HN = 25.46 mL · kg^-1 · min^-1, P = 0.50; women: PD = 20.10 vs HN = 16.20 mL · kg^-1 · min^-1, P = 0.35). Likewise, there was no significant differences in time(max) between women (PD = 5.2 vs HN = 5.4 min, P = 0.20). Comparison of time(max) between men did show a significant difference (PD = 9.5 vs HN = 13.10 min, P = 0.02). Conclusions: Although there were no significant differences in V̇O(2max) between the men, the comparison of time(max) indicates those with PD were unable to exercise as long before reaching V̇O(2max), indicating that individuals with PD may be less efficient during exercise and therefore unable to exercise as long before reaching V̇O(2max). Although women with PD had a higher V̇O(2max), comparisons of V̇O(2max) and time(max) between those with PD and HN resulted in no significant differences.