Schedule of Events | Symposia

Underlying mechanisms to exercise-induced working memory improvements

Poster Session B - Sunday, March 30, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Sofi Sandstrom^1,2 (sofi.sandstrom@umu.se), Emma Simonsson^1,2, Mattias Hedlund¹, Nina Lindelöf¹, Erik Rosendahl¹, Carl-Johan Boraxbekk^1,2,3,4; ¹Umeå University, ²Umeå center for Functional Brain Imaging, ³University of Copenhagen, ⁴Copenhagen University Hospital Bispbjerg

Introduction: Physical exercise has shown positive effects on cognitive functions such as working memory (WM) among older adults, however large individual differences in response to exercise exist and underlying mechanisms are not well-understood. We tested the hypothesis that change in leg strength following high intensity training (HIT) will improve WM via changes in prefrontal functional brain activity. Methods: This study was based on the Umeå HIT study, a randomized controlled trial assessing the effects of 12 weeks of watt-controlled HIT versus moderate intensity training for non-exercising older adults. Forty-three participants (66-79 years, 56% females) underwent functional magnetic resonance imaging while performing a WM task. Outcomes of interest were changes in WM performance, as measured by a WM composite of three tasks, WM task activation, cardiorespiratory fitness, and leg strength. Results: For WM performance, we found no significant between-group difference in change, however there was a significant within-group change for HIT in the WM composite. For HIT, change in leg strength significantly predicted increased activation in the right BA 44, which in turn was associated with improved performance in the in-scanner WM task. Cardiorespiratory fitness did not predict change in brain activity. Conclusion: Exercise-induced increases to WM performance may be associated with increased leg strength inducing positive effects on the right BA 44.

Topic Area: EXECUTIVE PROCESSES: Working memory