Lying Reverse Frog Crunch
Lying Reverse Frog Crunch Exercise Description
The Lying Reverse Frog Crunch is a floor-based core exercise that curls the pelvis toward the ribcage while the hips are flexed, knees are apart, and the soles of the feet are together. The movement emphasizes posterior pelvic tilt and controlled lumbar flexion rather than swinging the legs. Primary emphasis is on the rectus abdominis, with the obliques assisting in stabilizing the pelvis and ribcage. The frog-leg position (hip abduction and external rotation) encourages quiet legs and helps you focus on initiating the motion from the abdomen. This variation builds precise pelvic control and trunk stability using only body weight and minimal space.
- Muscle Groups: Abs, Core, Waist
- Target Muscles: Rectus Abdominis
- Assisting Muscles: External Obliques
- Stabilizing Muscles: Iliacus, Internal Obliques, Psoas Major, 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: Single-joint
- Muscle Location: Stomach
- Movement Direction: Vertical
- Muscle Position: Anterior
- Gender: Female
How To Do The Lying Reverse Frog Crunch Exercise
‘- Lie supine on a mat with arms by your sides, palms down, head and shoulders relaxed.
– Bring hips and knees to about 90° flexion; press the soles of your feet together and let your knees fall apart (frog/butterfly).
– Set your ribs down, lightly brace, and gently flatten your low back by posteriorly tilting the pelvis.
– Exhale as you draw your pubic bone toward your ribcage, curling the tailbone off the floor 1–2 inches.
– Keep thighs roughly at the same angle to your torso; avoid kicking, swinging, or pulling with the arms.
– Maintain head and shoulders on the floor; keep the neck relaxed and gaze up.
– Pause briefly at the top with abdominal tension; breathe steadily.
– Lower slowly until the sacrum returns to the floor, stopping before the low back arches.
– Keep knees apart and feet together throughout; move only as far as you can maintain control and a neutral ribcage.
Lying Reverse Frog Crunch Tips
‘- Lie on your back with arms by your sides, palms down, head and shoulders relaxed on the mat.
– Bring hips and knees to about 90° flexion with soles of the feet pressed together and knees dropped apart.
– Before moving, set your ribs down, lightly brace, and gently flatten your low back with a posterior pelvic tilt.
– Exhale as you draw your pubic bone toward your ribcage, curling the tailbone 1–2 inches off the floor.
– Keep your thighs at roughly the same angle to your torso; avoid kicking or swinging the legs.
– Do not pull with the arms; let them rest by your sides for support only.
– Keep head and shoulders on the floor with a relaxed neck and gaze up.
– Pause briefly at the top, maintaining abdominal tension and steady breathing.
– Lower slowly until the sacrum returns to the floor, stopping before your low back begins to arch.
– Keep knees apart and feet together the entire time, moving only as far as you can maintain control and a neutral ribcage.
Lying Reverse Frog Crunch Beginner Introduction
The Lying Reverse Frog Crunch is a bodyweight core move performed on the floor, centered around gently rolling the pelvis toward the ribcage while the legs stay in a relaxed butterfly-style position. Hips are bent, knees drift outward, and the bottoms of the feet meet, so the motion mainly comes from the midsection rather than from swinging or kicking the legs. This creates a small, controlled lift of the tailbone and a smooth rounding through the lower back instead of a big, jerky movement.
This exercise places most of the workload on the abs, with the side abs helping to steady the pelvis and ribcage. Because the upper body rests on the ground and the neck remains relaxed, attention shifts to subtle control through the trunk. The frog-leg leg position reduces excess leg effort, highlighting slow, deliberate curling from the core. Overall, it offers a compact way to build refined pelvic control and a more stable midsection using only body weight and a small amount of floor space.