Author(s): SCHERRER, S., EGGER, S., LIU, X., WICK, A., XIN, L., RASCH, B., LAUBER, B., TAUBE, W., Institution: UNIVERSITY OF FRIBOURG, Country: SWITZERLAND, Abstract-ID: 2070

INTRODUCTION:
As the average age of the global population continues to increase, pathological neurodegeneration and the resulting cognitive decline have become major public health concerns. Because effective treatments are limited once neurodegeneration begins, strategies to prevent or slow cognitive decline are essential. Although physical exercise is associated with cognitive benefits, the mechanisms underlying these effects remain insufficiently understood. For example, elevated lactate levels, potentially reflecting impaired oxidative metabolism, and reduced sleep quality are both linked to an increased risk of cognitive decline, but it remains unclear whether these factors can be mitigated through resistance training.
METHODS:
We therefore investigated whether 12 weeks of explosive lower-body resistance training leads to decreased brain lactate levels and improved sleep quality in community-dwelling older adults. Thirty-six participants aged 64 to 81 years completed pre and post assessments, including lactate concentrations in the sensorimotor cortex measured with 7 T magnetic resonance spectroscopy, objective sleep parameters assessed with wearable polysomnography, and subjective sleep quality measured using the SF-A/R questionnaire for single-night comparison and the Pittsburgh Sleep Quality Index (PSQI) for a one-month sleep quality assessment. Participants were assigned either to a resistance training group (RT) with three sessions per week or to a control group (CON) instructed to maintain their usual lifestyle.
RESULTS:
Compared with CON, repeated-measures ANCOVA with sex as a covariate showed that RT had significantly reduced resting lactate concentrations (p = .026, partial eta squared (p_et2) = .23), improved objective sleep efficiency (p = .036, p_eta2 = .14), and increased total sleep time (p = .034, p_eta2 = .14) after training. No significant Group x Time interactions were observed for subjective sleep quality. In the RT group, the additional sleep time was predominantly spent in REM sleep (paired t-test; p_bonf. = .048, d = 0.60).
CONCLUSION:
These findings suggest that resistance training may support brain health in older adults with fragmented sleep and impaired oxidative brain metabolism.