What muscles does the Flexion Leg Sit-up (bent knee) work?

This exercise primarily targets your upper abdominal muscles and overall core, with secondary engagement of the obliques. The bent-knee position helps isolate the abs while reducing strain on the lower back compared to traditional sit-ups.

Do I need any equipment for the Flexion Leg Sit-up (bent knee)?

No equipment is required; it’s a bodyweight move you can perform anywhere with a flat surface. A yoga mat or soft floor can make it more comfortable and reduce stress on your tailbone.

Is the Flexion Leg Sit-up suitable for beginners?

Yes, beginners can safely perform this exercise by focusing on controlled movements and engaging the core throughout. Start with fewer repetitions to build strength before progressing to higher volumes.

What are common mistakes to avoid when performing bent-knee sit-ups?

Avoid pulling on your neck with your hands, as this can cause strain. Keep your lower back pressed into the floor and move in a smooth, controlled motion rather than using momentum.

How many sets and reps should I do for the Flexion Leg Sit-up?

For general core strengthening, aim for 2–3 sets of 10–15 repetitions. Increase the reps gradually as your core strength improves, making sure you maintain proper form.

What are the safety tips for the Flexion Leg Sit-up?

Perform the exercise on a cushioned surface to protect your spine, and engage your core throughout to avoid lower back strain. If you experience discomfort, stop and reassess your form before continuing.

Are there variations of the Flexion Leg Sit-up I can try?

You can add a twist at the top of the movement to work the obliques more, or hold a small weight for increased resistance. Advanced exercisers may perform the move more slowly to intensify muscle engagement.

Flexion Leg Sit-up (bent knee)

Target Muscles

Primary:

Abs

Upper Abs

Secondary:

Obliques

Equipment Required

Bodyweight

Exercise Type

Reps Only

How To Do

Lie on your back with knees bent and feet flat on the floor, hands behind your head or crossed over your chest. Engage your core as you lift your head and shoulders off the ground while bringing your knees toward your chest. Keep your lower back pressed into the floor throughout the movement.

Step-by-Step Instructions

Lie on your back with your knees bent and feet flat on the floor.
Place your hands behind your head, or crossed over your chest.
Engage your core and lift your head and shoulders off the ground, keeping your lower back pressed into the floor.
As you lift, bring your knees towards your chest, flexing your hips and knees.
Slowly lower your head and shoulders back to the ground, extending your legs back to the starting position.
Repeat for the desired number of repetitions.

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Frequently Asked Questions

What muscles does the Flexion Leg Sit-up (bent knee) work?: This exercise primarily targets your upper abdominal muscles and overall core, with secondary engagement of the obliques. The bent-knee position helps isolate the abs while reducing strain on the lower back compared to traditional sit-ups.
Do I need any equipment for the Flexion Leg Sit-up (bent knee)?: No equipment is required; it’s a bodyweight move you can perform anywhere with a flat surface. A yoga mat or soft floor can make it more comfortable and reduce stress on your tailbone.
Is the Flexion Leg Sit-up suitable for beginners?: Yes, beginners can safely perform this exercise by focusing on controlled movements and engaging the core throughout. Start with fewer repetitions to build strength before progressing to higher volumes.
What are common mistakes to avoid when performing bent-knee sit-ups?: Avoid pulling on your neck with your hands, as this can cause strain. Keep your lower back pressed into the floor and move in a smooth, controlled motion rather than using momentum.
How many sets and reps should I do for the Flexion Leg Sit-up?: For general core strengthening, aim for 2–3 sets of 10–15 repetitions. Increase the reps gradually as your core strength improves, making sure you maintain proper form.
What are the safety tips for the Flexion Leg Sit-up?: Perform the exercise on a cushioned surface to protect your spine, and engage your core throughout to avoid lower back strain. If you experience discomfort, stop and reassess your form before continuing.
Are there variations of the Flexion Leg Sit-up I can try?: You can add a twist at the top of the movement to work the obliques more, or hold a small weight for increased resistance. Advanced exercisers may perform the move more slowly to intensify muscle engagement.