# Lying Single Leg Lift - Canonical: https://fitwill.app/exercise/7734/lying-single-leg-lift/ - Media ID: 7734 - Primary muscle: Quads - Body part: Thighs - Equipment: Body Weight - Video: https://fitwill.app/videos/7734/lying-single-leg-lift.mp4 ## Description The Lying Single Leg Lift is a bodyweight floor exercise performed from a supine position. You lie on your back with one knee bent and the foot planted for stability, while the opposite leg stays extended. From there, you raise the straight leg up toward the ceiling by hinging at the hip, then lower it back down under control. The highlight in the movement falls on the front of the thigh, especially the rectus femoris, which works doubly hard here because it crosses both the hip and the knee and has to keep the knee locked out as the leg travels upward. Because the knee stays straight throughout, the quadriceps are active the entire time, but the hip flexors do the actual lifting. The lower abdominals work to keep your pelvis and low back quiet while the leg moves. This combination makes the exercise useful for people who want to strengthen the hip flexors through a long range without loading the spine, or who need to train straight-leg control for activities like kicking, running, or getting up and down from the floor. The setup matters more than it looks. The bent knee on the working side's partner leg anchors your pelvis, which is what allows you to lift the extended leg without arching your lower back or letting your ribs flare. If the planted foot is positioned well and your back stays in contact with the floor, the hip flexors and quads do the work; if it is not, the lower back takes over and the exercise quickly becomes uncomfortable. Execution is simple but demands control. Lift the straight leg until it approaches vertical or reaches your comfortable end range, pause briefly, then lower it slowly back toward the floor without letting it fully relax or your back arch. Move at a tempo you can own — roughly two seconds up, a short hold, two to three seconds down. Breathe steadily and avoid holding your breath as the leg climbs. This movement fits well into warm-ups, core circuits, and rehabilitation-style training blocks. It requires no equipment beyond floor space, so it is easy to do at home, and it scales naturally: bend the non-working leg more or reduce the range if you struggle to keep your back flat, or slow the lowering phase to make it harder. Stop short of the floor with the working leg if your back starts to peel away — that is your working range. ## Instructions 1. Lie on your back on the floor with your arms relaxed at your sides, palms facing down. 2. Bend your left knee and place the left foot flat on the floor close to your hips; keep the right leg fully extended with the knee straight. 3. Gently press your low back toward the floor and brace your abdominals so your pelvis stays level before you start moving. 4. Keeping the right knee locked out and the toes relaxed, raise the straight leg by hinging at the hip toward the ceiling. 5. Continue lifting until the leg is near vertical or you reach your comfortable end range without the back arching. 6. Pause for a beat at the top, keeping the knee straight and the leg lined up over the hip. 7. Lower the leg slowly back down, stopping just above the floor or at the point where your back begins to lift away. 8. Exhale as you lift the leg and inhale as you lower it, keeping the breath continuous. 9. Complete all repetitions on the right leg, then switch the bent knee to the other side and repeat with the left leg. ## Tips & Tricks - If your low back arches as the leg descends, do not lower all the way to the floor — stop at the height where your back can stay flat; that is your true working range. - Point the toes toward the ceiling rather than letting the foot flop outward; a turned-out foot usually means the hip is rotating and the quad is no longer holding the knee straight. - The planted foot is your brake pedal — press it into the floor slightly to stop the pelvis from tilting as the extended leg rises. - Avoid pressing your hands hard into the floor to hoist the leg; the arms are for balance, not for cranking the hip upward. - A soft or bending working knee is the most common fault — actively squeeze the thigh straight before the first rep and re-set it every few reps. - Do not rush the lowering phase; most of the quad and hip flexor challenge comes from the eccentric part, so take two to three full seconds down. - If one side lifts noticeably higher than the other, match your range to the tighter side for a few sessions instead of chasing symmetry with momentum. - Keep the neck relaxed and gaze at the ceiling — craning forward to watch the leg tenses the shoulders and pulls the ribs up. ## Frequently Asked Questions ### Which muscles does the Lying Single Leg Lift work? The straight-leg position keeps the quadriceps, especially the rectus femoris, engaged throughout, while the hip flexors perform the actual lifting. The lower abdominals stabilize the pelvis so the lower back does not arch. ### Why does one knee stay bent during the Lying Single Leg Lift? The bent knee and planted foot anchor the pelvis and take strain off the lower back. With both legs extended, most people cannot keep their back flat, and the exercise turns into a low-back arch instead of a hip movement. ### Is the Lying Single Leg Lift good for beginners? Yes, it is one of the most approachable single-leg floor exercises because it uses no equipment and the bent-knee position makes it easier to control. Beginners should start with a shorter range and focus on keeping the back flat rather than lifting the leg high. ### How high should I lift my leg? Lift to roughly vertical or wherever you can keep the knee straight and the low back in contact with the floor. Height is not the goal — control of the knee and pelvis is. ### Why does the front of my thigh cramp during the Lying Single Leg Lift? The rectus femoris works hard to hold the knee straight while the hip is flexing, and cramping is common when the muscle is unfamiliar with that combined demand. Lower the leg slightly, shake it out, and build up repetitions gradually. ### What is the most common mistake in this exercise? Letting the lower back arch and the pelvis tilt as the leg lowers. The fix is to shorten the range — stop the descent before the back lifts — and keep the bent foot pressed into the floor. ### Can I do the Lying Single Leg Lift instead of hanging leg raises? It is a sensible substitute when hanging is not an option or grip fatigue limits your core work. It trains the same hip flexion pattern with less load, and the bent support knee makes pelvic control easier. ### How many reps and sets should I do? Two to three sets of 8 to 12 controlled reps per side works well for general strength. If the goal is warm-up or mobility preparation, one lighter set of 8 per side is enough. ### Should my knee be completely straight the whole time? Yes, the locked-out knee is what keeps the quadriceps involved and makes this a thigh and hip exercise rather than a generic leg raise. If full extension is uncomfortable, straighten the leg as much as you can and build from there. ### Is it safe to do every day? Because it is a low-load bodyweight movement, it can be performed frequently, including as a daily warm-up. If you feel pinching at the front of the hip, reduce the range or skip a day rather than pushing through it.