勉強の前に20分歩くと集中力が上がる？ 効果は小さめ、運動のあとは少し休んでから

Do you feel too tired to study after sports? Light exercise may actually help your brain. In one study, children walked for about 20 minutes. After the walk, they did better on an attention test. Many other studies also show that the brain works a little better after light exercise.

But the effect is small. Also, it is better to rest a little after exercise. So try a short walk, rest, and then study.

Many students believe that exercise makes them too tired to study, but research suggests the opposite may be true for light exercise. In a 2009 study at the University of Illinois, 20 children aged about nine or ten walked on a treadmill at a moderate pace for around 20 minutes.

Afterward, they performed better on an attention test and on a reading test than after resting, although there was no difference in math or spelling. A 2012 meta-analysis of many studies found that a short session of exercise slightly improves mental performance, but the effect was small and depended on how hard people exercised and when they were tested. Tests within ten minutes after exercise were slightly worse, so rest a little first.

Physical activity is often thought to drain the energy needed for studying, yet research on acute exercise, meaning a single session of activity, points in a more encouraging direction. In a 2009 study by Hillman and colleagues, 20 children of about nine or ten completed 20 minutes of moderate treadmill walking on one day and rested on another.

After walking, they responded more accurately on an attention task that required ignoring distractions and scored higher on reading comprehension, though not on arithmetic or spelling. A 2012 meta-analysis of 79 studies by Chang and colleagues confirmed that cognitive performance tends to improve slightly after exercise. The overall effect was small, however, and it varied with exercise intensity and with how soon testing took place.

Right after strenuous exercise, the benefit was unclear, and tests within ten minutes were slightly worse. The Hillman study had a small sample, and large classroom trials have not consistently shown effects on academic achievement. A 2026 study of university students found that short active breaks improved self-reported motivation and attention, but it did not measure test scores. A brisk walk before studying is a sensible, low-cost habit, but not a guaranteed route to better grades.