Exercise guide
Straight Hip Single Leg Curl On Stability Ball
- Intermediate
- Isolation
- Rep-based
- Lower legs
- Waist
This unilateral isolation exercise targets the hamstrings and glutes by combining knee flexion with isometric hip extension, significantly challenging core stability.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Lie flat on your back with one heel centered on the stability ball and the other leg extended straight up toward the ceiling.
- Place your arms flat on the floor by your sides for stability.
- Lift your hips off the ground until your body forms a straight line from your shoulders to the heel on the ball.
How to do it
- Exhale and pull the ball toward your glutes by bending your knee, keeping your hips high and level throughout the movement.
- Pause for one second at the peak of the contraction, squeezing the hamstring of the working leg.
- Inhale and slowly extend your leg back to the starting position using a controlled 3-second tempo.
Form checklist
- Keep your hips fully extended and level; do not let them sag toward the floor as you curl.
- Maintain a neutral spine and engaged core to prevent excessive arching in the lower back.
- Ensure the non-working leg remains vertical and steady to avoid using momentum.
- Press your heel firmly into the center of the ball to maintain control and maximize tension.
Pro tips
- Focus on the mind-muscle connection by imagining you are pulling the ball underneath your hips to maximize hamstring shortening.
- Keep your ankle dorsiflexed (toes toward shin) to better engage the entire posterior chain.
Make it harder
- Cross your arms over your chest to remove the floor support and increase the stability requirement.
- Perform a 5-second eccentric (lengthening) phase to increase time under tension.
Frequently asked
- What muscles does the straight hip single leg curl on stability ball work?
- The straight hip single leg curl on stability ball primarily targets the glutes and hamstrings, and also works the abs and obliques as secondary muscles.
- What equipment do you need for the straight hip single leg curl on stability ball?
- The straight hip single leg curl on stability ball uses stability ball.
- Is the straight hip single leg curl on stability ball good for beginners?
- The straight hip single leg curl on stability ball is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.
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