Muscle building and Physical exertion

Muscle building noun - Exercise that builds muscles through tension.

Physical exertion and muscle building are semantically related. In some cases you can use "Physical exertion" instead a noun phrase "Muscle building".

Physical exertion noun - The activity of exerting your muscles in various ways to keep fit.

Muscle building and physical exertion are semantically related. Sometimes you can replace phrase "Muscle building" with "Physical exertion", this phrases are similar.