Advanced movement. Use appropriate equipment, safety pins or spotters, and a load you can control. If you are unfamiliar with the movement, learn the technique before attempting the programmed intensity.
What it trains
hamstrings
Also: gluteus maximus, calves, spinal erectors
Equipment
glute-ham developer, or a partner and a pad
Setup
Anchor the feet in a glute-ham developer, or have a partner hold the ankles with the knees on a pad.
Start with the body upright from the knees, trunk braced.
Execution
1.Lower the torso forward by extending the knees under control.
2.Resist the whole way down, keeping the hips extended and the body in a straight line.
3.Pull yourself back up by contracting the hamstrings.
Breathing
Inhale as you lower, exhale as you pull back up.
Form cues
Keep the hips straight — do not fold at the waist.
Fight the descent; that is where the strength is built.
Squeeze the glutes to stop the lower back arching.
Common mistakes
Breaking at the hips and turning it into a back extension.
Falling to the bottom instead of lowering under control.
Attempting full reps before you can control the eccentric.
Scaling & substitution
Pushing off the floor at the bottom, or performing only the lowering phase, keeps the movement usable while strength builds.