As a natural, non enhanced athlete, most important aspects of your training are the workload (volume, intensity, frequency) that you put your body through and your recovery (stress levels, sleep, genetics, nutrition, training experience). The more advanced you become, the more recovery aspect comes into play, doing volume of 25-30 total sets per workout, working on big body parts (legs, back, shoulders, chest) 3-4 times a week might be alright when you are starting out, but it for sure will take you into a cortisol and overtraining grave as the time goes on. It proved itself multiple times through my training years when following competing bodybuilders advice just won't work, at least when trying to build muscle as a natty. Going from 25 sets to 15-18 per workout has made a huge difference, i feel better, perform better, look better. I continue to burn fat and build muscle simultaneously, which didn't seem possible before. Main idea is to still train hard, but make sure you do it smart. More is often not better.