Seated Leg Curl - Phase 1 - Day 2 - Muscular Endurance. The Seated Leg Curl exercise is a great finishing exercise for the hamstrings. Set the machine up properly with your butt & back right up against the back of the machine. Squeeze the weight down for a full contraction in the hamstring & bring it up in a controlled manner for a stretch. This exercise is such a good stretch movement because it has a 90 degree angle at the hips. So when the legs are straight, you get an effective stretch in the hamstrings. Don't rock the body with the movement, swing with the upper body, or use a shortened range of movement. Aim for 3 sets of 15 reps with only 30 seconds rest in between sets. Nick Jones - World Bodybuilding Champion & Kymbel Hunt.