Acute aerobic exercise improves memory across intensity and fitness levels.

The present study was designed to examine the impact of exercise intensity and aerobic fitness on free recall, judgments of learning (JOLs), and metacognitive accuracy. In Experiment 1, 30 college students engaged in either (1) no exercise, (2) light exercise (55% of predicted maximal heart rate), or (3) moderate exercise (75% of predicted maximal heart rate) on three different days. In Experiment 2, 29 high-fit students (VO2 max ≥ 70th percentile) and 28 low-fit students (VO2 max ≤ 50th percentile) completed sedentary and light exercise conditions. In both experiments, free recall scores significantly increased in the exercise conditions compared with the sedentary condition, but JOL magnitude and metacognitive accuracy were largely unaffected. These results demonstrate that exercise can improve recall at both light and high intensities, and that the benefit can be obtained by individuals regardless of their fitness level.