Resistance & Intensity combined build muscle. Sorry, not long runs on a treadmill or lifting light weight for endless reps. Train that way and your body has no reason to change it's composition (burn fat, build lean muscle tissue, build functional strength. ) That is about as simple as I can make it.
A combination of heavy resistance, multi joint exercises up to four in one set ( group) and little to no rest between sets. This is the key to unlock the door to a lean muscular body, for life! H.I.G.T combined with boxing is an exciting and challenging way to train.
Richard