Someone at the gym told me that there are diminishing returns when it comes to lifting weights more than once per week, but this seem to go against common sense, because as I understand it, it only takes 48-72 hours for muscles to fully recover. I normally just do an upper and lower body workout once per week, but I would be willing to do it twice per week if it were to mean twice the amount of hypertrophy. Or are we looking at diminishing returns? Thanks in advance.