45 degree one leg hyperextension (arms in front of chest)
- Target muscle
- Erector Spinae, Hamstrings
- Synergist muscles
- Gluteus Maximus
- Equipment
- Body weight
- Body part
- Hips
- Type
- Strength
The 45 degree one leg hyperextension is a single-leg bodyweight exercise that targets the lower-back erector spinae and the hamstrings, with the gluteus maximus assisting the hip extension. Performed on a 45-degree hyperextension bench with one leg supporting at a time and the arms crossed in front of the chest, it builds posterior-chain strength while exposing and correcting left-to-right imbalances.
How to do the 45 degree one leg hyperextension (arms in front of chest)
- 1Set the foot and hip pad of a 45-degree hyperextension bench to your height and step into it facing down.
- 2Place one foot on the platform and let the other leg hang free or rest it lightly, so a single leg supports the movement.
- 3Rest the front of your hips on the pad with the edge just below your hip crease, and cross your arms in front of your chest.
- 4Brace your core and let your torso hinge down toward the floor, keeping your back flat and your supporting leg firm.
- 5Lower until you feel a stretch in your hamstring and lower back, without rounding your spine.
- 6Drive your hips into the pad and extend through the hamstring and glute to raise your torso back in line with your supporting leg.
- 7Pause briefly at the top with your body straight, avoiding any backward overextension.
- 8Complete your reps on one leg, then switch to the other leg and repeat for the opposite side.
Form tips
- Hinge from the hips rather than the lower back so the hamstrings and glutes share the load with the erectors.
- Keep the supporting leg's knee soft and stable so the effort stays in the posterior chain, not the joint.
- Move slowly in both directions instead of swinging, and stop the rise once your body is straight.
- Train both legs with the same reps and effort to even out left-to-right strength differences.
- Add a light weight plate held to your chest only once you own clean bodyweight reps on each leg.
Common mistakes
- Hyperextending the back at the top, which compresses the spine and removes tension from the hamstrings and glutes.
- Rounding the spine at the bottom instead of hinging from the hips, which loads the lower back unsafely.
- Using momentum to swing the torso up, which cheats the rep and reduces work for the posterior chain.
- Pushing through the supporting knee rather than driving the hips, which shifts effort off the target muscles.
- Training only the stronger leg, which leaves left-to-right imbalances unaddressed.
Frequently asked questions
What muscles does the 45 degree one leg hyperextension work?
It primarily works the erector spinae of the lower back and the hamstrings, with the gluteus maximus assisting as a synergist during hip extension.
Why do it on one leg instead of both?
Working one leg at a time exposes and corrects left-to-right strength imbalances and increases the demand on each side's hamstrings and glutes, since one leg carries the full load.
Is the 45 degree one leg hyperextension good for beginners?
Yes. It uses only your body weight and a hyperextension bench, so beginners can master the single-leg hinge pattern before adding any weight to the chest.
How many sets and reps should I do?
For most people 3 sets of 10–15 controlled reps per leg works well. Prioritize a full hinge and a strong contraction at the top over chasing high rep counts.
Where should I feel this exercise?
You should feel it in the hamstrings and lower back of your supporting leg, with the glute working as you extend the hip — not as strain in the lower spine.
