Medicine Ball Lying Leg Raise
What Is the Medicine Ball Lying Leg Raise?
Medicine Ball Lying Leg Raise is an isolation exercise that primarily targets the core, with heavy involvement from the hip flexors and a constant squeeze from the inner thighs to hold the ball in place. It is an intermediate-level movement performed lying face up with a medicine ball gripped between the feet and the arms resting on the floor for support.
Adding the ball is what separates this from a standard Lying Leg Raise. The extra weight sits at the far end of a long lever, so the resistance on the lower abs increases sharply even with a light ball. It also gives you a way to progress the exercise numerically instead of just adding reps, which matters once bodyweight leg raises stop being challenging.
The emphasis is on the lower portion of the rectus abdominis and the hip flexors working together. As the legs travel up toward vertical, the abs resist the pelvis being pulled into an anterior tilt and then finish the rep by curling the tailbone slightly off the floor. That last part is the piece most people skip, and it is where the abdominal work actually happens rather than the hip flexors doing all of it.
Variations include bending the knees to shorten the lever if straight legs cause the back to arch, pausing at the top for extra time under tension, and lowering slowly to a point just above the floor rather than resting the ball down between reps. Anyone whose training already includes the Hanging Straight Leg Raise can use this as a floor-based alternative when grip or a bar is not available.
The cue that matters most is keeping the lower back in contact with the floor throughout. Press the ribs down, feel the abs take tension before the legs move, and squeeze the ball hard with the ankles so the adductors stay engaged and the ball does not slip.
Muscles Worked
- Rectus Abdominis (Lower)
- Primary
- Rectus Abdominis
- High
- Rectus Femoris
- High
- Adductor Longus
- Medium
- External Oblique
- Medium
- Tensor Fasciae Latae
- Medium
- Sartorius
- Low
- Latissimus Dorsi
- Minimal
Instructions
- Lie face up on a mat with your legs extended and place a medicine ball between your feet or ankles.
- Squeeze the ball firmly with your ankles so it is secure before you start moving.
- Rest your arms on the floor out to your sides, palms down, to anchor your upper body.
- Press your lower back into the floor and brace your abs to lock the ribs down.
- Keeping your legs straight, raise them until they are roughly vertical over your hips.
- At the top, curl your tailbone slightly off the floor to finish the repetition with the abs.
- Lower your legs under control, keeping your lower back flat, until the ball is just above the floor.
- Pause briefly without letting the ball rest, then repeat for the prescribed repetitions.
Common Mistakes
Letting the lower back arch
Allowing the lumbar spine to lift off the floor on the descent shifts load from the abs onto the lower back.
Resting the ball down between reps
Touching the floor at the bottom releases the tension and turns a continuous set into a series of separate lifts.
Stopping at vertical
Finishing the rep when the legs reach vertical skips the small tailbone lift that gets the lower abs involved.
Dropping the legs fast
Letting the weighted legs fall gives up the eccentric portion of the rep and yanks on the pelvis.
Loose grip on the ball
Failing to squeeze the ball with the ankles lets it slip mid-set and takes the adductors out of the exercise.
Pulling with the arms
Pushing hard through the hands to help the legs up reduces the work the abs have to do.
Injuries
Medicine Ball Lying Leg Raise is a medium risk exercise when performed with proper technique. The lower back is the main area of concern, because the weighted lever pulls the pelvis into an anterior tilt on the way down and any loss of control transfers that force into the lumbar spine.
The classic failure is the lower back arching off the floor as the legs descend. When that happens, the hip flexors are pulling on the spine with nothing resisting them, which is where most post-workout back soreness from leg raises comes from. Keeping the ribs pinned down, stopping the descent higher, and using a lighter ball all fix it. The hip flexors themselves can also get overworked, so if you feel the front of the hips cramping instead of the abs working, reduce the range or the load. Dropping a heavy ball on the shins is a smaller but real risk, so use a soft ball rather than a slam ball where possible.
Start light, around 2 to 4 kg, and only add weight once you can control the full range without the back lifting. If straight legs are too much, bend the knees to shorten the lever, or regress entirely to the Reverse Crunch or the unweighted Lying Leg Raise. To progress, add a pause just above the floor or move to the Hanging Straight Leg Raise.
Stop the set as soon as the lower back leaves the floor on the descent, if you feel a pinch in the front of the hip, or if the ball starts slipping. Anyone with an acute disc problem, a hip flexor strain, or current lower back pain should stay with the Dead Bug or Hollow Hold until symptoms settle.
- Primary Focus
- Core
- Equipment
- Medicine ball
- Modality
- Strength
- Difficulty
- Intermediate
Alternative Exercises
Frequently Asked Questions
- Q: How heavy should the ball be?
Start at 2 to 4 kg. The lever is long, so even a light ball feels heavy, and going too heavy is the fastest way to lose control of the lower back position.
- Q: What if my lower back keeps lifting off the floor?
Shorten the range by stopping the legs higher, or bend your knees to reduce the lever. If that still does not work, drop the ball and rebuild control with the Reverse Crunch.
- Q: Should I put my hands under my hips?
You can, and it makes it easier to keep the pelvis in place, but it also masks a lack of control. Arms out to the sides on the floor, as shown, is the better default once you can hold position.
- Q: How many reps should I aim for?
Eight to twelve controlled repetitions per set works well for most people. Add weight rather than chasing very high rep counts once form holds up.
- Q: Can I do this without a medicine ball?
Yes, the unweighted Lying Leg Raise is the same movement and a sensible starting point. The ball is simply a way to add resistance once bodyweight is no longer challenging.