Here’s the abstract:¹

We investigated how 9-year-olds and young adults performed a working memory task under different difficulty conditions while walking on a treadmill. Stride-length and stride-time variability tended to decrease with cognitive load in young adults, whereas children showed an increase in walking variability when cognitive load was very high. Participants in both age groups improved their cognitive performance when walking at their preferred speed as opposed to sitting or walking at a fixed, non-preferred speed. We conclude that the interaction of walking and cognitive performance is influenced by sharing resources between two tasks, and that performance improvements in cognition may be caused by an exercise-induced activation of resources.