Scientists discovered that brief intense exercise is more effective in improving heart health than an equivalent amount of long distance training, especially in children. Compared to people who do endurance training, those who perform intense exercises need much less time, distance, and calories burned to gain the same cardiovascular benefits.
In a study that was published in the American Journal of Human Biology, researchers recruited 57 volunteer school children, 47 boys and 10 girls, and divided them randomly into two exercise teams. One team was assigned to do high intensity exercises, while the other performed moderate intensity exercises. Both teams underwent three weekly exercise sessions over a period of seven weeks. During each exercise session, the high intensity team performed a number of 20-meter sprints over a period of 30 seconds, whereas the moderate intensity team ran steadily for 20 minutes.
At the end of the study, the moderate intensity team had completed a total of 420 minutes of exercise, and the high intensity team had trained for 63 minutes. The estimated energy expenditures for the moderate intensity team and the high intensity teams were 4410 kcal and 907.2 kcal respectively. Results from the study showed that both teams demonstrated improved cardiovascular risk factors. However, over the course of seven weeks, the moderate intensity team’s total exercise time was six times higher than that of the high intensity team. Therefore, the improvements in cardiovascular risk factors in the high intensity team occurred in just 15% of the total exercise time.
The results of the study suggest that brief and intense exercise is a more time-efficient way to improve cardiovascular risk factors in youths than endurance exercise. The exercise programs that the subjects underwent resulted in notable improvements in cardiorespiratory fitness, body composition, blood pressure, and insulin resistance.