Exercise guide
Medicine Ball Russian Twist Legs-Up
- Intermediate
- Compound
- Rep-based
- Waist
This exercise builds rotational power and core stability by forcing the obliques to rotate the torso while the rectus abdominis maintains a static V-sit position. It is highly effective for developing midsection definition and functional trunk strength.
Reviewed by the Crucible Fit team · Updated June 2026
Muscles worked
Setup
- Sit on the floor with your knees bent and feet flat, holding a medicine ball with both hands at chest height.
- Lean your torso back to a 45-degree angle, keeping your spine neutral and your chest lifted.
- Lift your feet 3-5 inches off the floor, balancing on your sit bones with your knees slightly bent.
How to do it
- Exhale as you rotate your torso to one side, bringing the medicine ball toward the floor near your hip.
- Inhale as you return to the center position, maintaining a tall posture and keeping your legs as still as possible.
- Exhale and rotate to the opposite side, ensuring the movement comes from your ribs and not just your arms.
- Continue alternating sides in a controlled, rhythmic tempo, focusing on the squeeze in your obliques.
Form checklist
- Keep your chest up and avoid rounding your shoulders or lower back.
- Minimize 'bicycling' or swaying of the legs; keep them locked in space.
- Follow the medicine ball with your eyes to ensure your entire upper torso is rotating.
- Maintain the 45-degree lean throughout the entire set to keep the abs under tension.
Pro tips
- Think about 'wringing out' your midsection like a wet towel at the end of each rotation to maximize oblique fiber recruitment.
- Squeeze your knees and ankles together to create a stable lower-body anchor, which forces the core to do all the work.
Make it harder
- Straighten your legs completely into a full V-position to increase the lever length and tension on the lower abs.
- Slow down the tempo to a 3-second count per rotation to eliminate momentum and increase time under tension.
Frequently asked
- What muscles does the medicine ball russian twist legs-up work?
- The medicine ball russian twist legs-up primarily targets the abs and obliques, and also works the serratus anterior as secondary muscles.
- What equipment do you need for the medicine ball russian twist legs-up?
- The medicine ball russian twist legs-up uses medicine ball.
- Is the medicine ball russian twist legs-up good for beginners?
- The medicine ball russian twist legs-up is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.