Straight Leg Opposite Sit-Up
Straight Leg Opposite Sit-Up Exercise Description
The Straight Leg Opposite Sit-up is a cross-body trunk-flexion exercise performed with the legs extended on the floor. It targets the rectus abdominis while the external and internal obliques drive the rotational component; the hip flexors assist as the torso rises. With the heels grounded and knees straight, you sit up and reach one hand toward the opposite shin or ankle, then lower under control. Expect a strong demand on anterior core bracing to keep the ribcage down and the pelvis stable as you rotate. Use smooth, segmental movement through the spine, maintain a neutral neck, and avoid using the arms for momentum. The goal is crisp trunk flexion with controlled rotation and an even, steady descent back to the mat.
- Muscle Groups: Abs, Core, Waist
- Target Muscles: Rectus Abdominis
- Assisting Muscles: External Obliques, Iliacus, Internal Obliques, Psoas Major
- Stabilizing Muscles: Multifidus, Transversus Abdominis
- Body Area: Upper Body
- Body Parts: Core, Torso
- Body Surface: Front
- Body Symmetry: Unilateral
- Equipment: Bodyweight
- Exercise Patterns: Other
- Exercise Type: Strength
- Functional Grouping: Trunk Flexors
- Joint Involvement: Multi-joint
- Muscle Location: Stomach
- Movement Direction: Rotational
- Muscle Position: Anterior
- Gender: Male
How To Do The Straight Leg Opposite Sit-Up Exercise
‘- Lie supine on a mat; legs straight, heels on the floor about hip-width apart.
– Extend arms by your sides; reach fingertips toward your feet (avoid pulling on your head/neck).
– Lightly posteriorly tilt the pelvis to gently flatten the low back; brace the abdominal wall.
– Inhale to prepare; exhale as you initiate the sit-up by curling your trunk and drawing ribs down.
– Reach your right hand toward your left thigh/shin while rotating your torso to the left.
– Keep chin slightly tucked and neck neutral; eyes toward the ceiling, not your knees.
– Keep both heels in contact with the floor; avoid lifting or swinging the legs.
– Pause when your hand reaches the outside of the opposite shin/ankle, maintaining control.
– Inhale as you lower with a slow, segmental roll-down; keep ribs stacked over pelvis.
– Repeat to the other side, matching range and tempo; move smoothly without jerking or bouncing.
Straight Leg Opposite Sit-Up Tips
‘- Keep your legs straight with heels on the floor about hip-width apart.
– Lightly posteriorly tilt your pelvis to gently flatten the low back, then brace your abdominal wall before you start.
– Extend your arms by your sides and reach your fingertips toward your feet; avoid pulling on your head or neck.
– Exhale as you initiate the sit-up by curling your trunk and drawing the ribs down.
– Reach one hand toward the outside of the opposite thigh/shin/ankle while rotating your torso toward that side.
– Keep your chin slightly tucked and neck neutral, with your eyes looking toward the ceiling rather than your knees.
– Keep both heels in contact with the floor throughout; avoid lifting or swinging your legs.
– Pause when your hand reaches the outside of the opposite shin or ankle, maintaining control at the top.
– Inhale as you lower with a slow, segmental roll-down, keeping your ribs stacked over your pelvis.
– Match range of motion and tempo from side to side, moving smoothly without jerking or bouncing.
Straight Leg Opposite Sit-Up Beginner Introduction
The Straight Leg Opposite Sit-up is a floor-based core move that blends an upward curl with a gentle twist through the torso. It’s designed around straight legs resting on the ground and grounded heels, so the effort centers on the abs, side abs, and hip flexors as the upper body lifts and rotates. One hand travels toward the opposite shin or ankle in a smooth, cross-body reach, then the spine gradually returns to the mat. This creates a combination of forward bend and rotation that challenges both strength and control through the mid-section.
Throughout the motion, the front of the core works to steady the ribcage and hips while the spine moves in a gradual, wave-like manner rather than all at once. The neck stays relaxed with the chin slightly drawn in, so the trunk—not the head or arms—drives the action. The emphasis is on precise, deliberate movement, an even rise and fall, and matching the effort from side to side for balanced core training.