# Lying Straight Leg Reverse Crunch - Canonical: https://fitwill.app/exercise/7737/lying-straight-leg-reverse-crunch/ - Media ID: 7737 - Primary muscle: Abs - Body part: Core - Equipment: Body Weight - Video: https://fitwill.app/videos/7737/lying-straight-leg-reverse-crunch.mp4 ## Description The Lying Straight Leg Reverse Crunch is a floor-based abdominal exercise where you lie on your back with your legs pointing straight up toward the ceiling, then curl your hips and pelvis up off the floor so your feet travel up and back over your body. Instead of pulling your chest toward your legs like a standard crunch, you flip the direction: your torso stays planted and your lower body does the moving. This shifts the workload heavily onto the lower portion of the rectus abdominis, the section of the six-pack muscle closest to your pelvis. The setup starts lying flat with your arms resting alongside your body, palms down for a little extra stability. Your legs are extended and raised roughly perpendicular to the floor. From there, you press your arms into the ground, exhale, and peel your hips off the floor by curling your tailbone upward, letting your legs drift back slightly over your head as your pelvis rotates. The key detail is that the lift comes from spinal flexion driven by the abs, not from simply swinging the legs with momentum. This exercise is a solid choice for anyone who has outdone basic crunches and wants more challenge without equipment. Because your legs stay vertical, the leverage is demanding but controlled, making it popular in core-focused training, calisthenics progressions, and as a stepping stone toward harder movements like hanging leg raises or toes-to-bar. It also suits people who find lying leg raises aggravate their lower back, since the hips stay supported and the range is shorter and more deliberate. The setup matters more than most people realize. Keeping your legs stacked over your hips at the start, rather than angled far past your head or dropped low toward the floor, determines how much tension lands on the abs versus how much strain ends up in the hip flexors or lower back. Your arms and the back of your shoulders act as the anchor for the entire rep, so pressing them firmly into the floor gives you a stable base to curl against. To execute it well, think of the movement as rolling your pelvis toward your ribcage, not lifting your feet higher. The feet only rise because your hips leave the floor. At the top, your hips should be clearly off the ground with your legs angled slightly back over you, then you lower with a slow, controlled descent until your tailbone touches down and your legs return to vertical. Rushing the lowering phase is the most common way this exercise loses its value. A few practical points: keep the movement quiet and controlled rather than jerky, avoid pushing your hands into the floor so hard that your torso lifts, and stop the set when your form starts depending on momentum. If you feel your lower back arching or popping off the floor, that is your cue to reduce the range or bend your knees slightly while you build control. ## Instructions 1. Lie flat on your back on an exercise mat with your legs extended and raised straight up so they are roughly perpendicular to the floor, stacked directly over your hips. 2. Place your arms alongside your body with palms facing down on the floor, and rest the back of your shoulders and head comfortably on the ground. 3. Brace your abdominal muscles and gently press your lower back toward the floor before you start moving. 4. Exhale and curl your tailbone and hips upward off the floor, thinking of rolling your pelvis toward your ribcage rather than pushing your feet higher. 5. Continue the curl until your hips are fully lifted and your legs have traveled slightly back over your body toward your head, keeping your knees as straight as comfortable. 6. Pause briefly at the top and squeeze your lower abs to hold the curled position. 7. Inhale and lower your hips back down in a slow, controlled descent until your tailbone touches the floor and your legs return to the vertical starting position. 8. Reset your brace, make sure your lower back is flat against the mat again, and begin the next repetition. 9. Keep your head and neck relaxed throughout, and stop the set if your hips start dropping quickly or your legs begin swinging. ## Tips & Tricks - The most common mistake is turning this into a leg swing: if your feet are moving but your hips are not leaving the floor, the abs are not doing the work. Slow the tempo down and focus on the tailbone lifting first. - Do not let your legs drift toward your head at the start. If they angle back before you curl, you shorten the working range and make the top position harder to control. - Press your palms lightly into the floor for balance, but avoid pushing so hard that your shoulders and upper back lift, which turns the rep into a partial shoulder stand. - If your lower back arches as you lower, that usually means your abs have fatigued and your hip flexors are taking over. Shorten the range by not lowering as far, or bend your knees slightly until control improves. - Keep your neck neutral and your gaze straight up. Craning your chin toward your chest adds tension in the neck without helping the abs at all. - A slow three-count lowering phase does more for this exercise than adding extra reps, because the abs work hardest controlling the descent of the hips. - If you cannot lift your hips at all with straight legs, start with a bent-knee reverse crunch to learn the pelvic curl, then progress to the straight-leg version. - Avoid jerking your legs to build momentum at the start of each rep. Every lift should begin from a still, braced position with legs stacked over the hips. ## Frequently Asked Questions ### Which muscles does the Lying Straight Leg Reverse Crunch work? The primary target is the lower section of the rectus abdominis, with strong support from the deep core muscles that stabilize the pelvis. The hip flexors assist as your legs travel, though the goal is for the abs to drive the pelvic curl. ### How is the Lying Straight Leg Reverse Crunch different from a regular crunch? In a regular crunch your torso curls toward fixed legs, while in the reverse crunch your torso stays on the floor and your hips and legs move. This places more emphasis on the lower abs and on controlling the pelvis. ### Is the Lying Straight Leg Reverse Crunch suitable for beginners? It can be challenging because straight legs create long leverage. Beginners often do better starting with a bent-knee reverse crunch or a shorter range, then progressing to the straight-leg version once they can lift their hips cleanly. ### Why do my hip flexors feel this more than my abs? The hip flexors naturally assist when the legs move, but if they dominate, you are likely swinging the legs instead of curling the pelvis. Slow down, focus on lifting your tailbone first, and keep the range to what your abs can control. ### Should my knees stay completely straight during the Lying Straight Leg Reverse Crunch? Legs should stay as straight as the name implies, but a small, comfortable bend at the knee is fine if full extension strains the back of your legs. What matters is that the hips curl up off the floor, not the exact knee angle. ### How high should I lift my hips at the top of the movement? Lift until your hips are clearly off the floor and your legs have angled slightly back over your body toward your head. If only your feet rise while your tailbone stays down, the rep is too shallow. ### Can I do the Lying Straight Leg Reverse Crunch without a mat? Yes, any firm, comfortable surface works since the exercise only uses body weight. A mat simply cushions your spine and gives your palms a bit of grip against the floor. ### What should I do if my lower back discomforts me during this exercise? Stop the set and check that your lower back stays pressed toward the floor at the start of each rep. Reduce the range, add a slight knee bend, or switch to a bent-knee reverse crunch, and avoid forcing repetitions through discomfort. ### How many reps of the Lying Straight Leg Reverse Crunch should I do? Aim for sets of 8 to 15 controlled reps where your hips lift on every rep and the lowering phase stays smooth. When you can no longer lift the hips cleanly, end the set rather than swinging through the remaining reps. ### Can the Lying Straight Leg Reverse Crunch help me progress to hanging leg raises? Yes, it trains the same pelvic curl pattern in a supported position, making it a useful stepping stone. Once you can lift your hips smoothly with straight legs, the hanging version adds grip demand and more hip flexor involvement.