Effects of moderate and vigorous exercise on memory and other mental abilities

INTERVENTION: Twenty‐si Xparticipants took part in a randomized, open, crossover clinical trial in which all participants completed three experimental conditions on separate days, such that 26 participants completed the rest condition, 26 participants completed the moderate‐intensity aerobic exercise condition and 26 participants completed the vigorous‐intensity aerobic exercise condition; before the experimental sessions, all participants underwent one preparticipation medical evaluation and one incremental cardiopulmonary exercise test on a cycle ergometer until maximal voluntary effort to individually determine heart rate and ventilatory thresholds used for exercise intensity prescription; the order of the three conditions was determined by computer‐generated block randomization among si Xpossible sequences, with 5 participants completing rest, moderate exercise and vigorous exercise, 4 completing rest, vigorous exercise and moderate exercise, 4 completing moderate exercise, rest and vigorous exercise, 4 completing vigorous exercise, rest and moderate exercise, 4 completing moderate exercise, vigorous exercise and rest and 5 completing vigorous exercise, moderate exercise and rest; each participant completed each condition once and the three sessions were separated by an interval of at least one week; each session lasted no longer than twenty minutes; in the rest condition the 26 participants remained seated on the cycle ergometer without pedaling, with an initial five‐minute resting period; in the moderate exercise condition the 26 participants completed a five‐minute warm‐up with progressive self‐selected workload followed by exercise at an intensity between the first ventilatory threshold and 60% of heart rate reserve and a rating of perceived exertion between 12 and 13 on the 6‐to‐20 Borg scale; in the vigorous exercise condition the 26 participants completed a five‐minute warm‐up with progressive self‐selected workload followed by exercise at an intensity between 70% of heart rate reserve and the second ventilatory threshold and a rating of perceived exertion between 15 and 17 on the 6‐to‐20 Borg scale; during the exercise conditions heart rate was continuously monitored and cycle ergometer workload was adjusted when necessary to maintain the prescribed intensity; in each of the three conditions all 26 participants completed, in the same order, the Multitasking test to assess cognitive flexibility lasting approximately four minutes, the 2‐back test to assess working memory lasting approximately two and a half minutes and the Go/No‐Go test to assess inhibitory control lasting approximately two and a half minutes, with a one‐minute interval between tests; participants and researchers were not blinded CONDITION: Healthy Volunteers ; Volunteers M01.955 PRIMARY OUTCOME: Expected outcome 1: Executive‐function performance during moderate‐ and vigorous‐intensity aerobic exercise was expected not to show a deterioration with an effect size equal to or greater than 0.5 compared with rest, assessed by response speed and the number or percentage of errors in the Multitasking, 2‐back and Go/No‐Go tests Outcome found 1: Lower response time was observed in the Go/No‐Go test during moderate and vigorous exercise compared with rest, with no significant difference in the percentage of commission errors; no significant differences between rest, moderate exercise and vigorous exercise were observed in response‐time or error measures in the 2‐back test or in response time, switch cost or errors in the Multitasking test SECONDARY OUTCOME: No secondary outcomes are expected INCLUSION CRITERIA: Individuals of both sexes aged between 18 and 60 years; physically active, performing between 150 and 300 minutes per week of moderate‐intensity physical activity or between 75 and 150 minutes per week of vigorous‐intensity physical activity; without relevant cardiovascular, respiratory or metabolic history