Never skip a leg day
Across the board, multijoint leg exercises top this list. In addition to recruiting more muscle mass into the movement, multijoint exercises generate greater release of the muscle-building hormones testosterone and growth hormone. The amount of muscle called into play is critical on leg day because there are so many large muscle groups involved: the glutes (three muscles), quads (four muscles), hamstrings (three muscles), and calves (two muscles). And that list doesn't even include stabilizer muscles that are also recruited into many multijoint movements!