Exercise-Induced Muscle Injury and Influence of NSAID Therapy on Kinematics of Downhill Walking in Older Adults

Non-steroidal anti-inflammatory drug (NSAID) therapy appears to be beneficial in reducing the inflammatory response to exercise in older individuals. The purpose of this study is to determine if NSAID therapy is effective for alleviating exercise-induced muscle dysfunction measured by gait kinematics. In the double-blind cross-over study, 15 older adults (60 c 8 yr) performed 8 sets of 8 unilateral eccentric (ECC) knee extension actions at 75% of the maximum load that could be lowered once, then consumed naproxen sodium or placebo for 10 days. Video data of participants' gait during decline walking were collected. Participants exhibited the following gait alterations: shorter step length (p = 0.04), reduced support time (p = 0.00), and more posterior relative center of mass positions (p = 0.02). There were no significant (p < 0.05) gait changes detected for the NSAID trial. Gait alterations were moderately correlated with indices of muscle injury (p < 0.05). These results suggest that NSAID's may protect against alterations in downhill gait following novel ECC exercise in older individuals.