V-Sit Crunch

The V-Sit Crunch is a floor-based bodyweight core exercise that combines a balanced V-sit position with a crunching motion of the torso and legs toward each other. It targets the rectus abdominis and hip flexors while demanding sustained balance on the sit bones, making it more challenging than a standard floor crunch. No equipment is required, and the exercise scales easily by adjusting range of motion or hold time.

Muscles Targeted

• Primary: Rectus abdominis, hip flexors
• Secondary: Obliques
• Tertiary: Quadriceps (isometric hold with legs extended), lower back stabilizers

Starting Position

Sit on the floor with your knees bent and feet flat on the ground. Place your hands on the floor just behind your hips, fingers pointing toward your feet. Engage your core and lean your torso back slightly while lifting your feet off the floor, balancing on your sit bones with your knees still bent.

Execution Steps

1. Brace your core before initiating any movement to protect your lower back throughout the exercise
2. Extend your legs forward while simultaneously leaning your torso back slightly, forming the top of a V shape with your body
3. Curl your torso forward and draw your knees back toward your chest at the same time, crunching your upper body and legs toward each other
4. Reach your hands toward your shins or feet as your torso and legs meet, achieving maximum abdominal contraction
5. Pause briefly at the point of peak contraction, keeping your balance on your sit bones
6. Extend back out to the V position under control, resisting the urge to let your legs or torso drop quickly
7. Repeat for the desired number of repetitions without resting your feet on the floor between reps

Form Cues

• Lead with the abs, not the neck: Curl from your rib cage toward your pelvis rather than yanking your chin toward your chest
• Keep the movement controlled: Momentum from swinging the arms or legs reduces the abdominal demand of the exercise
• Maintain a braced core throughout: A loose core allows the lower back to round excessively under the balancing demand
• Exhale on the crunch, inhale on the extension: Consistent breathing helps maintain core tension and rhythm
• Keep your balance point on your sit bones, not your tailbone, to avoid lower back strain

Common Mistakes

• Straining the neck: Pulling the head forward with the hands or neck flexors instead of the abs causes neck discomfort. Keep a small gap between your chin and chest and let the abs do the work.
• Using momentum: Swinging the arms and legs to generate speed reduces time under tension for the abs. Slow the tempo and control both directions of the movement.
• Rounding the lower back excessively: Letting the lower back collapse under the balancing demand increases strain. Keep a slight, controlled curve rather than fully slumping.
• Not extending the legs fully: A shortened leg extension reduces hip flexor and lower ab engagement. Straighten the legs as much as your hamstring flexibility allows.
• Holding the breath: Breath-holding increases intra-abdominal pressure unnecessarily and disrupts rhythm. Breathe out on the crunch and in on the extension.

Variations

• Bicycle crunch: Adds rotation and alternating leg movement to increase oblique involvement
• Hollow body hold: An isometric variation that builds the same balanced, braced position without the crunching motion
• Tuck-up: A regression that keeps the knees bent throughout, reducing hip flexor demand for beginners
• V-up: A more advanced variation that starts lying flat and folds the body into a full V each rep
• Weighted V-sit crunch: Holding a light plate or dumbbell at the chest increases resistance for advanced trainees

Tips for Progression

• Increase the hold time at peak contraction before returning to the extended position
• Progress from the tuck-up regression to the full V-Sit Crunch as hip flexor and ab strength improve
• Add light external resistance once bodyweight reps become easy to control
• Slow the tempo on both the crunch and extension phases to increase time under tension

Training Notes

Train the V-Sit Crunch 2-3 times per week as part of a core-focused block, using 3 sets of 8-15 controlled reps with 45-60 seconds of rest between sets. It pairs well with anti-extension or anti-rotation core work to balance out the spinal flexion emphasis, and works best placed near the end of a session once the nervous system doesn't need to prioritize heavy compound lifts.