The number of systematic reviews on the effects of exercise on aerobic fitness and muscle strength in people with spinal cord injury (SCI) has recently increased. However, the results of some of these reviews are inconclusive or inconsistent. To strengthen recommendations, this overview was undertaken to assimilate evidence about the effectiveness of different types of physical activities, exercises, and therapeutic interventions for improving aerobic fitness and muscle strength in people with SCI. Cochrane Overview of reviews methods were adopted to undertake this overview. An online search was conducted in August 2018 on eight databases based on predefined search criteria. Potential systematic reviews were screened, selected, and assessed on methodological quality by two independent authors, and discussed and resolved with a third author, when necessary. Only systematic reviews published in the English language were included. The protocol was registered on PROSPERO. Overall, 16 systematic reviews were included (aerobic fitness, n = 10; muscle strength, n = 15). For all 16 reviews, the quality of evidence was rated as "critically low." Despite low evidence, this overview strengthens the existing guidelines for people with SCI, providing specific advice on exercise domains (types, intensities, frequency, and duration) for improving aerobic fitness and muscle strength. The evidence from this overview suggests that ergometry training with/without additional therapeutic interventions (20 min, moderate to vigorous intensity, twice weekly for 6 weeks) may improve aerobic fitness; similarly, resistance training with/without additional therapeutic interventions (three sets of 8-10 repetitions, moderate to vigorous intensity, twice weekly for 6 weeks) may improve muscle strength.
Keywords: aerobic fitness; exercise; muscle strength; spinal cord injury; systematic review.