Why you have to choose your training music wisely

Let's get straight to the point. What do you expect from the music you listen to while you train? Do you expect it to just keep you company? Or to motivate and energize your central nervous system for you to be able to 'feel' that rush of intense emotions? If it's the first, you're doing it wrong. If it's the second, you're doing it right! I'll tell you why.

The importance of a resting period for muscle hypertrophy

Without an adequate resting period after a workout, the fact is, you won't see any real gains in muscle mass other than the temporarily increased size from inflammation (study). That's probably the main reason why you're trying "so hard" but can't see the muscles growing, aside from not having a correct diet and/or supplementation, or having a really small number of muscle fibers due to genetic factors, or a disease, or a syndrome (or the combination of these), which eventually brings you to the conclusion that you are a hard gainer, although that's probably not the case.