This one is age old debate among bodybuilders. How long should you rest? This 8 week study already confirms what most already know. Short amounts of rest (30s) combined with low load but many reps seems to be ideal for hypertrophy. Heavier load seemed to increase circulating levels of growth hormone but with less noted hypertrophy.
So what I take from this is that maybe human growth hormone doesn’t actually mean more muscle? Hypertrophy will always be more complex than simply one hormone on itself. I encourage people to now go google”mTOR” and keep reading on the subject!
Here’s the study https://www.ncbi.nlm.nih.gov/pubmed/28032435/