Mass building comes with a set of rules. That means starting your leg workout with the most challenging exercises and heaviest loads, hitting your thighs from a variety of angles, keeping the volume (number of total sets and reps) high, and training to muscle failure.
Altering your foot placement on the leg press allows you to recruit leg musculature in slightly different ways. Putting your feet up higher on the sled shifts some of the emphasis from the quads to the hams and glutes because a greater degree of hip flexion/extension is taking place. Also, don’t shortchange the depth of your knee bend—which should reach 90 degrees—by going too heavy, limiting glute and hamstrings activation. Unless you’re following a pre-exhaust routine, save the single-joint movements for last.