The Secret To The Super Human Energy Levels Of Kids

Ever wonder how kids can run around all day and never seem to get tired? A new study suggests it's because their muscles resist fatigue in a similar way to those of elite endurance athletes!

The study, asked young boys, untrained men and endurance athletes to perform high intensity exercise, then looked at how quickly their muscles fatigued and recovered.

The researchers put the participants through their paces by having them perform vigorous activity on a stationary bike.

They found the boys' muscles didn't tire easily — even when performing at a similar level to the endurance athletes.

"The picture we get is that, in a high intensity exercise bout, kids fatigue at the same rate as elite athletes," said researcher Professor Tony Blazevich, from Edith Cowan University.

"They may even recover more quickly than elite athletes … which might be why kids recover so rapidly when they do bouts of play or activity."

Professor of Health Science at the University of South Australia, Tim Olds, said the study was interesting — but stressed it didn't mean young children were as fit as endurance athletes.

In order to understand why kids have such good endurance and recovery, you need to understand how the body makes energy.

There are two broad ways to generate energy: one is aerobically … the other process is anaerobically.

Anaerobic energy generation produces lactate and when high levels of lactate build up in muscles, it causes fatigue.

However kids don't have as highly developed anaerobic systems as the average adult … therefore they don't produce a lot of lactic acid, and thus they don't seize up after repeated bouts of exercise.

So essentially it doesn't mean that these kids are super fit, it just means that they haven't yet developed their anaerobic capacity


As well as helping explain why 10-year-old boys seem so indefatigable, the study could be useful in showing where to focus training efforts in young athletes.

The study shows that kids are actually pretty good at playing, stopping, playing, stopping, playing, and stopping. So that might mean that playing sports where they just get to run around a lot is much more enjoyable than doing other forms of deliberate exercise like adults may do.

The research is also a step towards better understanding how the risk of developing diseases such as cancer, cardiovascular disease and diabetes increases as we age.

With the rise in diseases related to physical inactivity, it is helpful to understand the physiological changes with growth that might contribute to the risk of disease.

Research has indicated that aerobic fitness, at least at the muscle level, decreases significantly as children move into adulthood, which is around the time increases in diseases such as diabetes occur.

It will be interesting in future research to determine whether the muscular changes observed are directly related to disease risk. These results might provide motivation for practitioners to maintain muscle fitness as children grow up; so it seems that being a child might be healthy for all of us.