Low-Load Resistance Exercise Improves Cognitive Function in Older Adults

Introduction: Resistance exercise (RE) training is widely recommended for increasing muscle strength and mass in older adults. RE is also a potential stimulus to improve cognitive functions (CF), but the best protocol for this purpose is unknown. Objective: To compare the effects of different RE protocols on CF in the same group of individuals. Methods: Twenty-four older adults were randomized (cross over) to control (CON) and lower limb RE protocols with high load (HL - 80% of 1RM), low load (LL - 30% of 1RM) and LL with blood flow restriction (LL-BFR - 30% of 1RM and 50% BFR). For CF assessment, participants underwent the Stroop test before and after each RE protocol. Results: Reduction in response time for Stroop neutral stimuli was greater after LL (effect size (ES) = -0.92) compared to CON (ES = -0.18) and HL (ES = -0.03), but was not different from LL-BFR (ES = -0.24). The reduced response time was associated with reduced parasympathetic modulation and increased cardiac output across protocols. Conclusion: LL was the most effective RE protocol to improve CF of older adults and a potential beneficial effect of LL-BFR on CF (non-significant) was identified. Therefore, LL resistance exercise appears to stimulate acute cognitive improvements in healthy older adults, probably through exercise-induced optimal autonomic modulation changes. Level of Evidence I; Therapeutic studies-Investigating the results of treatment.