Nice work on the torso and arms, the shapes there are quite good. I suggest redrawing the legs from scratch though, they look withered and mutated. Look at more reference material for that, perhaps even yourself in the mirror.
Also, you are pillow shading really badly. I hardly know where to start with advice on fixing this, but you need to think of the shape of the entire object, not just shade one ab, then another ab, then a bicep, then a pec. They are all part of one overall shape and light is not going to behave by highlighting the middle of every muscle and shading the outside rim. The light catches edges facing towards it, and is less present on surfaces facing away or surfaces shielded by other surfaces. I see a bit of understanding of this on certain parts, but you need to apply it thoroughly and completely for any effect.
Look into head anatomy as well, for proportions and shape. The eyes go half way between the top of the skull and the bottom of the chin for instance.