An extensive review of research looking at the effects of a single bout of exercise has concluded that:
- the most consistent behavioral effects of acute exercise are
- improved executive function
- enhanced mood
- decreased stress levels
widespread brain areas and brain systems are activated
Executive functions include attention, working memory, problem solving, cognitive flexibility, verbal fluency, decision making, and inhibitory control.
These positive changes have been demonstrated to occur with very low to very high exercise intensities, with effects lasting for up to two hours after the end of the exercise bout.
While brainwaves are all enhanced across the brain, hippocampal theta brainwaves are particularly enhanced by exercise, and the effects of this suggest that exercise particularly helps with tasks that depend on hippocampal-prefrontal interactions. Exercise also helps increase blood flow to the frontal regions.
One of the most dramatic effects of exercise is on neurochemical levels, including neurotransmitters and growth factors (such as BDNF).
 . The Effects of Acute Exercise on Mood, Cognition, Neurophysiology, and Neurochemical Pathways: A Review. Brain Plasticity [Internet]. 2017 ;2(2):127 - 152. Available from: http://content.iospress.com/articles/brain-plasticity/bpl160040