weight lifting, the best activity there for any human to do, doesn't need to be intensive, just something to make the little things stronger
He should try Taekwondo.I am a martial artist and you should look into "Tiger Rock Martial Arts" their great with kids and their also the worlds largest Martial arts franchise.They teach kids that when they learn Martial arts to only use it on people who is attacking you and they teach "stranger danger".Teaches what to do if theirs a stranger trying to get you somewhere and tells them how to get away.He can also take jujit-su at that academy,if you pay for one martial art you can take different ones there for free.I took a lot of martial arts there including boxing.So he gets different ones for the price of one! I also take tumbling and theirs boys that take it.Just look for a gymnastics academy near you and they should have it.Almost every academy has it,theirs a lot of boys in gymnastics also.Do what he wants to do,show him some different sports on youtube that you wouldn't mind for him to do and see which ones he likes better.
wrestling is a good marital art to do when you are young
Swimming!
Or find a football team or something like that that's for very small children.
But swimming is the best.
