No long-term benefits from resistance training on brain grey matter volumes in active older adults at retirement age

This study investigated whether one year of resistance training (moderate or heavy intensity) affected brain grey matter volume over a four-year period in older adults (mean age 66). Participants (n=276) were randomly assigned to heavy resistance training (HRT), moderate intensity training (MIT), or a non-exercising control group (CON). MRI scans at baseline, 1, 2, and 4 years showed all groups experienced similar declines in total grey matter, hippocampal, and prefrontal cortex volume, with increased white matter hyperintensities. No significant differences were observed between training groups. A weak association was found between leg strength and white matter hyperintensity volume, but it did not hold after statistical correction. The study suggests resistance training does not prevent age-related brain atrophy in this population. Limitations include the active baseline lifestyle of participants, which may have masked any potential training benefits.

Given that resistance training did not significantly alter brain structure over time in already active older adults, maintaining an overall active lifestyle—including aerobic exercise—may be more beneficial for long-term brain health. While resistance training remains crucial for muscle strength and functional health, individuals should focus on diverse physical activity rather than relying on strength training alone to preserve grey matter volume.