Exercise after traumatic brain injury: is it a double-edged sword?

This article describes the effects of exercise on neural plasticity after traumatic brain injury (TBI). There is strong evidence that indicates that exercise has neuroprotective effects by activating specific neuronal circuits and increasing molecules that enhance synaptic plasticity. Findings obtained from experimental models of TBI are discussed to support the use of exercise as a rehabilitative tool. These studies indicate that injury characteristics are likely to influence the time window for therapeutic exercise. Results of human and animal studies suggest that premature postconcussive exercise may be deleterious by exacerbating postconcussive symptomatology and disrupting restorative processes. A better understanding of the mechanisms that influence exercise after TBI will contribute to improving guidelines for the return to exercise activities and to the successful use of exercise as a therapeutic tool.