Smith Machine Stiff-Legged Deadlift
The Smith machine stiff-legged deadlift is a hip-hinge movement done on a fixed vertical track, lowering the bar toward your shins with a slight knee bend held constant throughout. It stretches and loads the hamstrings hard, with the glutes and lower back helping control the hip hinge, and the fixed path removes the need to keep the bar close to your body the way you would with a free barbell. It's a useful way to build hamstring strength and flexibility together.
Why it works
Bending forward at the hips while keeping your knees only slightly bent puts most of the load on your hamstrings, which lengthen under tension as your torso lowers and then contract to pull you back upright, with your glutes and lower back assisting the hip hinge. On a free barbell deadlift variant, you also have to actively keep the bar traveling close to your shins to avoid it drifting forward, which shifts stress onto your lower back if you lose that path. The Smith machine's fixed rail keeps the bar directly in front of you automatically, so your focus stays entirely on the hip hinge and the hamstring stretch. Because the knees stay almost locked throughout, the lower back and hip flexors also work harder to control the tilt of your pelvis than they would in a squat pattern, which is part of why this variation usually calls for lighter loads than a standard deadlift.
Set up
- Set the bar at hip height and grip it slightly wider than shoulder width.
- Stand with your feet hip-width apart, knees only slightly bent.
- Unrack the bar and let it settle in front of your thighs.
- Brace your core and keep your shoulders pulled back before starting.
How to do it
- Unrack the bar and stand tall with a slight bend in your knees.
- Hinge at your hips, pushing them back as you lower the bar down the front of your legs.
- Keep your knee bend roughly constant throughout the descent.
- Lower until you feel a strong stretch through your hamstrings, or until the bar reaches mid-shin.
- Drive your hips forward to return to standing, squeezing your glutes at the top.
- Rotate the bar to re-rack it once your set is complete.
Form cues
- Hips push back first, not your knees bending forward.
- Bar stays close to your legs the whole way down.
- Knee bend stays roughly the same throughout the rep.
- Back stays flat, not rounded, as you hinge forward.
Breathing: Inhale as you hinge forward and lower the bar, exhale as you drive your hips forward to stand back up.
Common mistakes
Bending the knees more as the bar descends, turning the hinge into a squat.
Fix: Keep your knee bend roughly constant and focus on pushing your hips straight back.
Rounding the lower back to reach further down.
Fix: Stop the descent once your back starts to round, even if that means less range of motion.
Letting the bar drift forward away from your legs.
Fix: Keep the bar brushing lightly down the front of your thighs and shins throughout the movement.
Rushing the descent instead of controlling the hamstring stretch.
Fix: Lower the bar slowly enough to feel the stretch build, rather than dropping into the bottom position.
How to program it
- This is a heavy hip-hinge movement for the hamstrings, so most lifters get the most out of it training it once a week at moderate loads, for 3 to 4 sets of 8 to 12 reps.
- Place it after your main squat or deadlift for the week rather than before it, since fatigued hamstrings make it harder to hold good hip-hinge form under heavier compound loads.
- Start lighter than you'd expect, since the deep hamstring stretch makes this movement feel harder at a given weight than a standard deadlift.
- Use a slow, controlled tempo on the way down rather than chasing extra reps, since the stretch under tension is the main driver of hamstring growth here.
Safety notes
- Stop the descent the moment your lower back starts to round rather than forcing extra range.
- Keep your knee bend roughly constant throughout the rep instead of letting it increase as you fatigue.
- If you feel sharp or pinching pain rather than a stretch in your hamstrings, stop the set and reduce the load.
Exercise profile
- Force
- Pull
- Mechanics
- Compound
- Category
- Strength
Frequently asked questions
What is the difference between a stiff-legged deadlift and a Romanian deadlift?
A stiff-legged deadlift keeps the knees almost completely straight, putting more emphasis on the hamstring stretch, while a Romanian deadlift allows a bit more knee bend and often starts from a standing position with the bar already in hand.
How many sets and reps for Smith machine stiff-legged deadlift?
3 to 4 sets of 8 to 12 reps at a moderate load works well, since the deep stretch makes lighter loads plenty challenging.
Why does my lower back hurt during stiff-legged deadlifts?
A rounded back under load shifts stress away from the hamstrings and onto the spine. Stop the descent as soon as your back starts to round, even if that means a shorter range of motion.
How far down should I lower the bar on a stiff-legged deadlift?
Go as far as you can while keeping your back flat, typically to around mid-shin. The hamstring stretch, not the bar height, should decide when to stop.