Poststroke Exercise is as Effective as Skilled Rehabilitation: Effects in Young and Aged Mice
Stroke is a leading cause of long-term disability, though current rehabilitative strategies fail to yield complete recovery. Focused training of the impaired limb improves functional outcome in rodents, but these strategies require intensive training that is difficult to practice in humans. Because aerobic exercise has been found to induce beneficial changes in the brain, it is a promising rehabilitative strategy after stroke. The current study investigated the effect of voluntary poststroke aerobic exercise on functional outcome in young and aged mice. Mice were trained on a skilled reaching task before receiving focal ischemic stroke and being subdivided into 3 different groups for rehabilitative training: traditional skilled reach rehabilitation, aerobic exercise, and control procedures. Both young and aged mice benefited from aerobic exercise after stroke, though the behavioral profile somewhat differed. Aerobic exercise in young mice yielded poststroke performance levels that were equivalent to preinjury levels. In aged mice, aerobic exercise accelerated improvement in motor performance without an effect on the absolute level of performance compared with controls. Our results suggest that aerobic exercise may be an effective alternative or adjunctive rehabilitative strategy after stroke. Potential mechanisms of this effect need to be further investigated.