Study: Teens Should Exercise Vigorously 20 Minutes a Day for Heart Health

The health benefits of exercise and fitness are well known, including reduced risks of obesity, diabetes, hypertension, heart disease, poor mental health, and associated death, but most kids don’t get enough exercise. A new study, “Intensity and Duration of Physical Activity and Cardiorespiratory Fitness,” in the July 2022 Pediatrics (published online June 13) found that adolescents might just need 20 minutes of panting and sweating a day to be healthy.

The World Health Organization guidelines recommend that children and adolescents undertake an hour of moderately intense or vigorous exercise per day to improve physical, mental, and cognitive health, but 81% of adolescents didn’t meet these daily activity goals in 2016. The new study found that teens need only about 20 minutes of exercise, but it must be vigorous, meaning sweating, panting, and getting red in the face.

Researchers studied 339 adolescents, ages 13-14, using wrist-worn accelerometers and 20-meter shuttle runs, to determine the cardiorespiratory fitness impacts of exercise. They found that boys get more vigorous exercise than girls, the fitness benefits of vigorous exercise plateau at about 20 minutes, and all less intense exercise, including the currently recommended moderate exercise, doesn’t seem to have the same relationship to cardiorespiratory fitness in adolescents.

Researchers concluded that these findings may guide future health guidelines for teenagers, offering more attainable daily exercise goals, but that more research is needed into whether 20-minute exercise interventions can help improve other aspects of cardiometabolic health beyond fitness.

The American Academy of Pediatrics is an organization of 67,000 primary care pediatricians, pediatric medical subspecialists and pediatric surgical specialists dedicated to the health, safety and well-being of infants, children, adolescents and young adults.