Most bodybuilders will pick the leg press over the squat, but according to new research, squats create a stronger anabolic stimulus (i.e., testosterone and growth hormone) than leg presses. 

Researchers had 10 well-trained male strength athletes train their legs on two occasions: on one occasion doing squats and on another using the leg press. Both times the athletes did six sets of 10 reps. For each training session they used weights that were 80% of the weight at which they could just manage one rep [1RM]. Blood samples were collected before, immediately after, and 15 and 30 minutes after exercise and analyzed for testosterone, growth hormone, and cortisol concentrations. 

The squat produced higher testosterone and GH and also cortisol levels immediately post-exercise and at 15 and 30 minutes post-exercise. 

Free-weight exercises appear to induce greater hormonal responses than machine-weight exercises utilizing similar lower-body multijoint movements and primary movers. The next time you train legs, don’t forget to get under the squat bar!