nice job. Ill try giving some Critiques..
his right pec muscle seems skinnier than the other one. The other pec muscle is more rounded.
His arms seem kinda wonky too. The biceps are too big compared to the rest of his arm. it makes his forearms too small. I think his hands could probably be bigger too.. not sure though
his legs need a little work in my opinion. His hamstrings are almost like giant marshmellows ;P. What I mean is that they are too big. Kind of puffin out the way its shaded. His knees are at different heights too.