The difference between muscle mass and muscle hypertrophy is that muscle hypertrophy is the increase in size of skeletal muscle while muscle mass is the weight of your body muscle.

an extra adjective that's not needed to describe muscle mass. Muscle mass is the amount of muscle in ones body as a % of their total weight.

It would have to be leg and muscle mass that is the answer on a+

Yes, because as the size of your muscle increases, the mass of your muscle increases. And when the mass of your muscle increases, so does the weight.

Answer There's no such thing. Muscle is muscle. There are no "lean" muscles or "bulky"muscles. Some people have a greater muscle mass, some have less muscle mass- but that mass is muscle. A pound of muscle is going to require energy to stay around. If you have a greater muscle mass, you'll have a greater metabolism.

He's right you know. This is really splitting hairs!