In vivo human brain biochemistry after aerobic exercise: preliminary report on functional magnetic resonance spectroscopy

Our aim was to disclose whether the positive psychological changes observed after a single bout of aerobic exercise have a biochemical correlate that can be visualized by proton magnetic resonance spectroscopy (MRS) of the human brain. Right-handed male volunteers underwent psychological testing and MRS of the frontal lobe of the left hemisphere, both before and after 20 minutes of jogging at about 70% of their maximal aerobic capacity. Although there was a significant decrease on the postexercise anxiety test scores ( z = −2.201, P < .05), there was no significant difference between the preexercise and postexercise scores of positive and negative affect. Considering both “amplitude” and “area under the curve” values calculated for the peaks of metabolites N-acetylaspartate (NAA), creatine, and choline, none were found to be significantly changed ( P > .05) after the exercise. This is, to our knowledge, the first study to report on a functional application of MRS to mood states. Because it offers the ability to directly measure metabolic changes in the brain during neuronal activation, “functional MRS” may be a potential new tool that may be used as an adjunct to functional magnetic resonance imaging.