Weights. I followed the 5x5 Stronglifts program and got to the point where I was doing 140 lbs squats, 110 lbs benchpress, 150 lbs deadlifts, 65 lbs overhead pr

Weights. I followed the 5x5 Stronglifts program and got to the point where I was doing 140 lbs squats, 110 lbs benchpress, 150 lbs deadlifts, 65 lbs overhead press, 75 lbs barbell row. 3 days a week at the gym, around 1 hour each. The phone app made it easy to track progress. I could see huge improvements in muscles and overall wellbeing. But a large part of it ensuring that you consume sufficient proteins, around (0.8 * body weight)g. I supplemented my diet with whey protein shake (2 scoops on gym days and 1 scoop on non). I started with a pretty unremarkable body and desk job lifestyle. Good luck.