He's small for his age, amongst the smallest boys in the class but he gets tired a lot quicker too.
Where they bound up the road home, he always has to stop and rest and moan. I know he's got short legs which don't help with fast running, but he's always complaining that his legs are tired.
He goes for half hour swimming lesson on sat am and afterwards he's totally zonked.
I don't know what's normal or what's not. Is it worth me going to the doctor?