Kids Are As Fit As Endurance Athletes Which Explains Why Parents Are So Damn Tired

by Jerriann Sullivan
Originally Published: 
Five happy kids running down a field
Image via bowdenimages/ Getty Images

Study: Children’s muscles resist fatigue like endurance athletes

There’s a reason your kids can play outside all day and still not want to go to bed: their muscles are similar to elite endurance athletes. Kids’ muscles resist fatigue and recover faster than the average adult, a new study shows.

Since kids are small and can’t complete tasks as quickly as adults, their muscles have evolved to make them more fit. The lead professor of the study explains: “During many physical tasks, children might tire earlier than adults because they have limited cardiovascular capability, tend to adopt less-efficient movement patterns and need to take more steps to move a given distance.” Sébastien Ratel, Associate Professor in Exercise Physiology who completed the study at the Université Clermont Auvergne, France, added: “Our research shows children have overcome some of these limitations through the development of fatigue-resistant muscles and the ability to recover very quickly from high-intensity exercise.”

To determine this, researchers had three different groups ride a stationary bike and tested how their muscles fatigued and recovered. The first group was made up of boys aged 8 to 12; the second group was made up of untrained adults who don’t regularly exercise at an intense level. The last group was made up of elite athletes who compete at a national level in triathlons or long-distance running and cycling, Science Daily reported. We won’t bore you with the details of every test the scientists ran on the participants, but you can find them in the scientific journal Frontiers, where the research was published. The main discovery: Kids outperformed the untrained adults in muscle fatigue and recovery.

“We found the children used more of their aerobic metabolism and were, therefore, less tired during the high-intensity physical activities,” Ratel explained. “They also recovered very quickly — even faster than the well-trained adult endurance athletes — as demonstrated by their faster heart-rate recovery.” He added: “This may explain why children seem to have the ability to play and play and play, long after adults have become tired.”

Um, yeah, sounds like it. If kids can recover from a run faster than a professional runner what hope do parents have at tiring the kiddos out?

Ratel and his co-author Anthony Blazevich, Professor of Biomechanics at Edith Cowan University, Australia, also had some helpful info for parents who have kids who love sports. “Many parents ask about the best way to develop their child’s athletic potential,” the researchers said. “Our study shows that muscle endurance is often very good in children, so it might be better to focus on other areas of fitness such as their sports technique, sprint speed or muscle strength.”

Basically, since kids have all this energy already coaches and parents should focus on helping young athletes get stronger, faster, or better at specific action like rebounding a basketball or sliding into home base. Blazevich added: “This may help to optimize physical training in children so that they perform better and enjoy sports more.”

If we can’t tucker them out with sports, at least we can keep them happy while they play them.

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