Enhancing brain health through resistance exercise: the effect of set number and intensity on brain- derived neurotrophic factor in older adults.

Background: This study investigated the impact of single sessions of resistance exercise with varying training intensities and doses on serum brain-derived neurotrophic factor (BDNF) levels in older adults. Methods: Nine older women aged ≥65 years were recruited for a study employing a balanced-order research design, which allowed for more robust comparisons of different resistance training modalities. All the participants completed four resistance training modalities: low-set high-intensity (LsHi), high-set high-intensity (HsHi), low-set high-repetition (LsHr), and high-set high-repetition (HsHr). Results: Serum BDNF levels were measured pre- and post-exercise for each modality. While the comparison of change rates (△BDNF) across the four exercise modalities did not reach statistical significance, serum BDNF levels were significantly elevated within-group following the LsHr modality. Notably, the LsHr modality showed a trend toward greater increases in serum BDNF, with average post-exercise levels increasing by more than 30%. Conclusion: Although no statistically significant differences in △BDNF were observed between the four modalities, these findings provide preliminary evidence that a muscular endurance-focused resistance training protocol (LsHr) may be effective in eliciting acute BDNF elevations in older adults. These results suggest that the interplay between training volume and intensity warrants further investigation. Given the exploratory nature of this study, our findings indicate that while LsHr shows potential, further research with larger cohorts is necessary to definitively establish whether training dose or specific modality configuration is the primary driver of BDNF modulation.