running is like the most complete workout someone can do, but is there any amount of sparring, bagwork, and shadowboxing that can make up for running? i just find them a lot easier of a way to break a sweat because i am focused on something else instead of just simply running, and it is more enjoyable. but can any amount of it be a substitute for running? what muscles and what areas of my body will benefit from boxing? can i still get as complete of a workout as i do if i just ran? what areas of my body can i get fat burned by doing it? and when i say spar, bagwork, and shadowboxing i mean with punches only also, can punching build muscle? also to bring up another point, how about swimming?