The effects of acute exercise intensity on memory: Controlling for state-dependence.

The present experiment evaluated the effects of varying intensities of acute exercise on free-recall memory performance while controlling for potential state-dependent effects. Forty-eight young adults completed a within-subject experiment involving seven primary laboratory visits. The encoding and retrieval phases were matched or mismatched by taking place either during rest or during a less than 5-min bout of acute exercise, and at moderate or vigorous intensity. We did not find evidence that the effects of acute exercise on memory were state-dependent but instead demonstrated that memory recall was greater when memory retrieval occurred during vigorous-intensity exercise compared to rest. These findings have important implications for the strategic placement of exercise during the phases of memory (e.g., acquisition, storage, retrieval) to optimize memory performance and suggest boundary conditions of state-dependent learning. We discuss various theoretical accounts (e.g., shift in metabolic resources across brain regions) to explain these findings.