Exercise guide · evidence-graded

Smith Machine RDL

The Smith machine Romanian deadlift is a hip hinge with a bar that runs on fixed vertical rails, taking it from standing down to around mid-shin and back up. It works the hamstrings and glutes under a deep stretch, with the rails doing the balancing a free barbell would ask of you.

Also called: Smith Machine Romanian Deadlift, Smith RDL, Machine Romanian Deadlift, Smith Machine Stiff-Leg Deadlift · Equipment: machine · Pattern: hinge

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How to do it

Step by step

Set the bar at about mid-thigh height and set the safety catches just below the lowest point you plan to reach.
Stand close to the bar with your feet hip-width apart, so the bar sits over the middle of your feet. Grip it overhand, just outside your thighs.
Stand tall, twist the bar off its hooks and brace your trunk. Keep a slight bend in your knees and your shoulders back.
Push your hips back and let your chest come forward, keeping your back flat and the bar close to your thighs.
Keep the same slight knee bend and go down until you feel a strong stretch in your hamstrings, usually with the bar just below the knees or at mid-shin.
Drive your hips forward to stand back up, squeezing your glutes at the top without leaning back.
After your last rep, stand tall and twist the bar back onto the hooks.

Coaching cues

Hips back, chest forward, back flat
Soft knees, same bend all the way
Bar close to your legs
Squeeze your glutes to stand tall
Stand straight at the top, no leaning back

In VALDA, these cues are one tap away on the exercise while you train.

Muscles worked

What it trains

Muscle	Role	Evidence
Hamstrings: biceps femoris (long head)	Prime mover	C
Gluteus maximus	Prime mover	C
Hamstrings: semitendinosus	Prime mover	C
Adductors: adductor magnus	Secondary	D
Erector spinae	Stabiliser	C
Forearm flexors	Stabiliser	D

Evidence grades: A = strong research base · B = good · C = limited · D = coaching consensus.

Common faults

What goes wrong, and the fix

Feet in the wrong place

Fix: Set your feet so the bar sits over the middle of your feet before unhooking.

Rounding the back to reach depth

Fix: Brace, keep your chest proud and go only as far as a flat back allows.

Squatting the rep

Fix: Keep the same slight knee bend and move by pushing your hips back.

Leaning back at the top

Fix: Finish with glutes squeezed and ribs down, standing straight.

Safety catches set too high or too low

Fix: Set the catches just below the lowest point of your rep before you start.

Programming

What the research says

Muscle growth · first choiceStrengthRehab & prehabGeneral fitnessEnduranceFat loss & conditioning

Machines versus free weights — Research comparing machine and free-weight training finds similar muscle growth. Strength gains tend to be specific to the equipment you train on, so the Smith version carries over less to a free barbell.
The stretched position — A trial of hamstring curls found more hamstring growth when training at longer muscle lengths, which the bottom of this hinge provides.
Effort — Studies show sets that finish a few reps short of failure capture most of the size benefit, and strength gains appear largely insensitive to how close to failure you train. The rails remove balance as a limit, so sets can be taken closer to failure.
Volume — Research links more weekly sets for a muscle to more growth, with diminishing returns. Around 10 or more hard sets a week has been associated with more growth than fewer than 5.
Rest — In trained lifters, rests of about 3 minutes between sets have produced greater strength and size gains than 1-minute rests.

Alternatives · VALDA FLEX

Swap it mid-workout

With VALDA Pro, FLEX offers alternatives like these when you swap an exercise mid-workout.

Log the smith machine rdl in VALDA, with these cues one tap away while you train and your history for it in one place.

General information about exercise technique, not medical advice. If you have an injury or a health condition, your healthcare provider is the right person to ask.