The concept of 'sarcoplasmic hypertrophy' (increase in fluid/non-contractile elements) versus 'contractile hypertrophy' (increase in actin and myosin) is still under investigation, with some initial work suggesting it's a combination of both occurring at different training phases.

“there's actually interesting work we actually have some tissue on its way to Auburn right now because one of the things that's been interesting it's like a broscience thing for years of piroplasm hypertrophy versus contractile hypertrophy and so what this is really positing is is the change really coming from fluid retention basically or is it actually enhanced of the contractile tissue which in this case would be an act amiin um seems to have some initial work there it's a little bit of both and it happens at different phases of training”