Parents run ragged by their children may have suspected it all along.
Youngsters have greater energy levels than professional endurance athletes, scientists have discovered, meaning it is virtually impossible for the average adult to keep up.
And for mothers and fathers hoping that tiring out their little ones will ensure a good night’s sleep, be warned.
Children also have a impressive recovery time, and will be back to their hyperactive best quicker than parents can say ‘lie in.’
“We found the children used more of their aerobic metabolism and were therefore less tired during the high-intensity physical activities,” said Sebastien Ratel, Associate Professor in Exercise Physiology who completed this study at the Université Clermont Auvergne, France.
“They also recovered very quickly – even faster than the well-trained adult endurance athletes – as demonstrated by their faster heart-rate recovery and ability to remove blood lactate.
“This may explain why children seem to have the ability to play and play and play, long after adults have become tired.”
Previous studies have shown that children do not tire as quickly as untrained adults during physical tasks and it was suggested they had energy profiles comparable to endurance athletes, but there was no evidence to prove it until now.
To find out, the researchers recruited 12 youngsters aged between nine and 11, 12 untrained men and 13 male endurance athletes who were national-level triathlon competitors or long-distance runners and cyclists.
All were asked to perform two seven second resistance sprints, followed by one minute recovery while their aerobic energy output was measured. On a second visit they were asked to complete the Wingate Cycle Test, which measures anaerobic output by asking participants to cycle as fast as they can for 30 seconds.
Because anaerobic exercise does not use oxygen it produces acidosis and lactate (often referred to as, lactic acid), which causes muscle fatigue. The participants’ heart-rate, oxygen levels and lactate-removal rates were checked after the cycling tasks to see how quickly they recovered.
It was found that children not only have fatigue-resistant muscles, but recover very quickly from high-intensity exercise – even faster than the well-trained adult endurance athletes.
During the Wingate test untrained adult’s power output fell by 51.8 per cent, and athletes by 41.8 per cent, but children’s only decreased by 35.2 per cent.
The researchers believe the findings could help develop athletic potential in children as well as improve our understanding of how our bodies change from childhood to adulthood.
“Many parents ask about the best way to develop their child’s athletic potential,” said co-author Anthony Blazevich, Professor in Biomechanics at Edith Cowan University, Australia.
“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.
“This may help to optimize physical training in children, so that they perform better and enjoy sports more.”
Dr Ratel added: “Our research indicates 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 we have observed are directly related to disease risk. At least, our results might provide motivation for practitioners to maintain muscle fitness as children grow up; it seems that being a child might be healthy for us.”
The research was published in the journal Frontiers in Psychology.