Children always have bags of energy and never run out of steam. Researchers said children are as fit as endurance athletes. Children recover from "high-intensity exercise" a lot quicker than athletes. Researchers compared the performance levels of children cycling to athletes cycling. They found the children used more of their aerobic metabolism and so were less tired during high-intensity physical exercise. The children recovered faster than the athletes."

The researchers' findings could help us understand how our body changes with age. It could help fight many diseases. A researcher said children were becoming less active and there was a rise in diseases related to this physical inactivity. Understanding the changes in our body as we grow might reduce disease. Children should play a lot and keep fit as they grow up so they become healthy adults. Children play long after adults have become tired.