Lying Knee Raise
- Target muscle
- —
- Equipment
- Body weight
- Body part
- Waist
- Type
- Strength
The Lying Knee Raise is a bodyweight exercise performed supine on the floor that trains the waist and abdominal area by drawing the knees toward the chest against gravity. Its low-impact, equipment-free nature makes it a practical core movement for all training levels and a reliable addition to any ab or conditioning circuit.
How to do the Lying Knee Raise
- 1Lie flat on your back on the floor or a mat with your legs extended and arms at your sides, palms pressing lightly into the floor for stability.
- 2Brace your core and press your lower back gently into the floor to establish a neutral spine before moving.
- 3Bend your knees to roughly 90 degrees, keeping your feet together or hip-width apart, and lift them so your thighs are perpendicular to the floor.
- 4Exhale and draw your knees toward your chest by contracting your abdominals, curling your hips slightly off the floor at the top.
- 5Pause for a moment at the top and feel the contraction through your waist and lower abdominal area.
- 6Inhale and lower your feet slowly back down, resisting gravity as you return to the starting position.
- 7Stop just before your feet touch the floor to keep tension in the core, then immediately begin the next rep.
- 8Complete all reps, then lower your feet fully and release the brace.
Form tips
- Press your palms or fingertips into the floor throughout the set to anchor your upper body and prevent rocking.
- Control the lowering phase — a slow descent creates more core tension than the lift itself.
- Focus on the abs pulling the knees in rather than swinging your legs with momentum.
- Keep your neck long and your head resting on the floor; avoid craning it forward during the movement.
- Breathe out on the way up and in on the way down to keep the core properly braced throughout.
Common mistakes
- Using momentum to swing the knees up instead of contracting the abs, which reduces core engagement and shifts strain to the hip flexors.
- Letting the feet drop too quickly on the descent, which removes tension from the waist area and makes each rep less effective.
- Arching the lower back away from the floor at the start or during the lowering phase, which compresses the lumbar spine and signals a loss of core control.
- Holding the breath throughout the set, which increases intra-abdominal pressure unnecessarily and can cause dizziness during higher-rep sets.
- Pulling the knees so far into the chest that the hips roll off the floor completely, shifting the work from the abdominal muscles to the hip flexors and lower back.
Frequently asked questions
What muscles does the Lying Knee Raise work?
The Lying Knee Raise primarily trains the waist and abdominal area. The movement requires the core musculature to flex the trunk and stabilize the pelvis as the knees are drawn toward the chest.
What is the difference between a Lying Knee Raise and a Hanging Knee Raise?
The Lying Knee Raise is performed on the floor, making it more accessible and easier to control since you can brace against the ground. The Hanging Knee Raise is done suspended from a bar, which requires additional grip and shoulder stability and allows a greater range of hip movement.
Is the Lying Knee Raise suitable for beginners?
Yes. Because it uses only body weight and is performed on the floor, it is one of the most beginner-friendly core exercises available. Focus on slow, controlled reps rather than high volume until the movement feels stable.
How many sets and reps should I do for the Lying Knee Raise?
A common starting point is 3 sets of 12–20 reps with a controlled tempo. Once that feels manageable, you can increase reps, add a pause at the top, or slow the lowering phase to increase difficulty.
Can I do the Lying Knee Raise every day?
The core can generally tolerate higher training frequency than larger muscle groups, but daily high-volume training can accumulate fatigue. Including it 3–4 times per week with adequate rest in between is a sustainable approach for most people.
