Effect of Duration of Acute Moderate Exercise on Exercise-elicited Cortical Activation and Cognitive Performance on Stroop Task: a Preliminary Examination

Recently a growing number of human studies have reported the beneficial influence of acute moderate exercise on cognitive functions. Neurocognitive investigations into such neural substrates have mainly been performed using electroencephalography. However, we recently introduced multichannel functional near-infrared spectroscopy (fNIRS), which is a noninvasive and nonrestrictive optical method to monitor cerebral hemodynamics reflecting regional neural activation. We found improved cognitive performance for Stroop interference elicited by an acute bout of moderate exercise that coincided with enhanced cortical activation in the dorsolateral prefrontal cortex. In a previous study, we set the duration of the exercise at 10 min, but the extent to which we could shorten exercise duration remained uncertain. Thus, here we assessed the effects of various durations of acute exercise on neurocognitive performance during an incongruent Stroop task. We present the first experimental evidence that a minimum of 10 min of acute exercise with an intensity of 50% of the maximum oxygen intake is necessary in order to improve cognitive performance on a Stroop interference test. In combination with facilities enabling strict physiological control, fNIRS is a promising tool that will serve to cultivate a novel application in sports science namely, elucidating, in detail, the cognitive effects of physical exercise.