Limb Deformation Tips

The two extremes area a deformed cylinder (top) and making the mesh adhere to the muscle direction and placement. There are two factors that should determine where on the range between these extremes you should pick.

The lower your polycount, the more you should tend towards the deformed cylinder method.

The more complicated the rig your engine allows, the more bones each vert can be influenced by, the more towards strictly muscle connection you should choose.