Examining the Impact of Light and Vigorous Acute Aerobic Exercise on Pattern Separation and Sustained Attention in Young Adults

PurposeThe study had two primary objectives: 1) To replicate and extend the literature by examining the dose-response relationship between acute aerobic exercise intensity and pattern separation performance during the Mnemonic Similarity Task and 2) To examine the dose-response relationship of acute bouts of aerobic exercise on sustained attention and inhibitory control. MethodsEighteen young adults completed three counterbalanced appointments, during which a 10-min exercise condition [rest (control condition), light intensity, or vigorous intensity] was implemented on a cycle ergometer, followed by cognitive testing. The Mnemonic Similarity Task was used to assess episodic memory and pattern separation, and the gradual-onset continuous performance task was used to assess sustained attention and inhibitory control. Heart rate, ratings of perceived exertion, and salivary cortisol were measured. ResultsAlthough a main effect of acute exercise on pattern separation performance was not observed, follow-up analyses revealed that the magnitude of exercise-induced performance enhancements in pattern separation were positively associated with baseline physical activity levels. Acute bouts of exercise enhanced sustained attention and inhibitory control abilities improved following bouts of light or vigorous intensity exercise compared with rest. There was no difference in sustained attention in the vigorous versus light intensity exercise condition.ConclusionsThe current study suggests that it may be important to consider baseline levels of physical activity when studying the acute effects of exercise on pattern separation performance. Bouts of light and vigorous intensity aerobic exercise improved both sustained attention and inhibitory control. Our results demonstrate that light intensity acute aerobic exercise was sufficient to enhance sustained attention and inhibitory control, and vigorous exercise intensity did not further improve or degrade cognitive performance.