Flexion Leg Sit Up With Bent Knee
Flexion Leg Sit Up With Bent Knee Exercise Description
The bent-knee sit-up is a bodyweight trunk-flexion exercise that primarily targets the rectus abdominis while the obliques and transverse abdominis contribute to lumbopelvic stability. Bending the knees reduces leverage for the hip flexors compared with straight-leg variations and can make the movement more comfortable for many people. The motion begins with segmental spinal flexion (curling the upper back off the floor) and typically continues into controlled hip flexion as the torso rises toward the thighs. Proper cervical alignment, ribcage control, and a steady eccentric return help focus the work on the anterior trunk and reduce unnecessary strain. Use smooth, deliberate motion without momentum to maintain control throughout the range you can perform with good form.
- Muscle Groups: Abs, Core, Waist
- Target Muscles: Rectus Abdominis
- Assisting Muscles: Iliacus, Psoas Major
- Stabilizing Muscles: External Obliques, Internal Obliques, Multifidus, Transversus Abdominis
- Body Area: Upper Body
- Body Parts: Core, Torso
- Body Surface: Front
- Body Symmetry: Other
- Equipment: Bodyweight
- Exercise Patterns: Other
- Exercise Type: Strength
- Functional Grouping: Trunk Flexors
- Joint Involvement: Multi-joint
- Muscle Location: Stomach
- Movement Direction: Other
- Muscle Position: Anterior
- Gender: Male
How To Do The Flexion Leg Sit Up With Bent Knee Exercise
‘- Lie supine with knees bent, feet flat and hip-width, and arms crossed over chest or hands lightly at the temples (do not pull the head).
– Set a neutral neck with a slight chin nod; keep gaze up, not forward at the knees.
– Lightly posteriorly tilt the pelvis so the low back contacts the floor; brace the abdominal wall.
– Initiate by curling the upper back off the floor—bring the sternum toward the pelvis, keeping ribs “down.”
– Continue to roll up through the spine; allow the hips to flex as the torso approaches the thighs while keeping feet grounded.
– Pause upright without collapsing the chest or rounding the shoulders forward.
– Lower in reverse: articulate the spine back to the floor under control, maintaining pelvic position.
– Exhale during the ascent; inhale on the controlled descent.
– Keep elbows wide, avoid yanking the neck, and avoid using momentum or bouncing.
Flexion Leg Sit Up With Bent Knee Tips
‘- Bend your knees with feet flat and hip-width to set up before starting each rep.
– Lightly nod the chin and keep your gaze up so the neck stays neutral instead of looking at the knees.
– Gently tilt the pelvis back so the low back contacts the floor, then brace the abdominal wall before you curl up.
– Start the movement by curling the upper back off the floor, bringing the sternum toward the pelvis while keeping the ribs “down.”
– Roll up through the spine segment by segment, allowing the hips to flex only as the torso approaches the thighs.
– Keep your feet grounded throughout the ascent so the hips and trunk do the work.
– At the top, pause upright without collapsing the chest or rounding the shoulders forward.
– Lower in reverse by articulating the spine back to the floor under control, keeping the same pelvic position.
– Exhale as you rise and inhale on the controlled descent to coordinate breathing with movement.
– Keep elbows wide, hands light at the temples, and avoid pulling on the head or using momentum or bouncing.
Flexion Leg Sit Up With Bent Knee Beginner Introduction
The bent-knee sit-up is a classic floor-based core exercise that emphasizes the abs while the side abs and deep abs help steady the midsection and hips. With the knees bent, leverage shifts away from the hip flexors compared with straight-leg versions, which can feel more accessible for many people. This variation centers attention on curling the torso rather than hinging primarily at the hips, highlighting strength and control through the front of the body.
During the movement, the upper back gradually rises from the floor as the chest travels closer to the thighs, then lowers back down in a smooth, measured way. The neck and head stay aligned with the spine so tension concentrates in the midsection instead of the neck. Gentle control through the ribs and pelvis helps the lower back stay supported against the ground, encouraging the abs to handle most of the effort. The emphasis is on a calm, unhurried tempo, relying on muscular engagement rather than swinging or bouncing for momentum.