Here is a little more evidence to suggest that regular moderate exercise is worth the effort at any age, and even if you are already quite far advanced along the path of age-related degeneration:
A decline in cognitive ability commonly occurs among older individuals. This study sought to explore the restorative effects of exercise in older patients with existing cognitive disabilities. Ninety-six patients with mild cognitive impairment were placed in an exercise program for six months. Following completion of the program, participants were assessed via the Chinese Mini Mental Status Examination (MMSE), Activity of Daily Living (ADL) assessment, and body movement testing and compared to a control group of patients with mild cognitive impairment who did not participate in the exercise program (N = 102).
Compared with the control group, patients who exercised showed improved cognitive function in immediate memory and delayed recall function. In addition, activities associated with daily living showed improvement, as did body movement, arm stability, and the appearance of rotation. Based on these results, we conclude that participation in an exercise program can improve patients' cognitive function, physical abilities, and body movement capacity.