Does 1-year of aerobic walking exercise slow brain aging in persons with multiple sclerosis?: Brief report.

INTRODUCTION: Accelerated brain aging represents a major feature of multiple sclerosis (MS), and long-term aerobic walking exercise training (ET) may slow brain aging in MS. METHODS: This study examined the effects of 1-year of remotely-delivered aerobic walking ET on brain age in 24 fully-ambulatory persons with MS who underwent 3T MRI. We calculated pre-to-post differences in brain age (derived based on a comparison of participant brain morphology with a large multi-age set of training images using brain-ageR (v2.1)), and compared such changes with the published, annualized rate of accelerated brain aging in relapsing-remitting MS (mean=1.24 years [SD=1.30]), given that 83% of the present sample presented with relapsing-remitting MS. RESULTS: 1-year of aerobic walking ET was associated with 0.74 years of brain aging. Such an effect translates into a 0.50-year slowing of brain aging relative to the annualized brain aging rate observed for persons with relapsing-remitting MS (i.e., 1.24 years of brain aging over a 1-year period). CONCLUSIONS: Our preliminary results may support the formal design and test of a larger trial of long-term, remotely-delivered and supported aerobic walking ET on brain age and its downstream consequences as a primary, clinically-relevant outcome in MS.