Answer:
The statement is actually false, because all children should see a doctor before starting a training program. The main reason of this, it's mainly because you never know if the kid has some kind of physical problem that could cause injuries.
For example, imaging that you go with the kid, and begin to exercise, after a while you notice that gets tired easily. Then, you realise that the kid is asthmatic, which means that you putted him or her in a risky situation, due to your ignorance about her or his health condition.