Exercise
LEG RAISE
Form cues
About
The lying leg raise is a bodyweight core exercise that trains the rectus abdominis in its lower portion and the hip flexors through a long-lever movement. Because the legs act as a long lever arm, even beginners quickly feel significant lower abdominal effort. Keeping the lower back pressed into the floor throughout the movement is the critical form requirement — once the back arches off the mat, the hip flexors take over and the ab training benefit is lost. The exercise builds the foundation for hanging leg raises and L-sit progressions.
Instructions
Step-by-step technique
Lie flat and anchor
Lie on your back with legs straight and arms at your sides, palms down. Press your lower back firmly into the mat and tighten your core before anything moves. If needed, hold onto something behind your head for stability.
Lower back pressed flat before every repRaise the legs to 90°
Exhale and lift both legs together, keeping them straight, until they are perpendicular to the floor. The pelvis should not tilt — the movement is purely a hip flexion with a stable spine.
Exhale up, legs reach 90°Lower with control
Inhale and slowly lower the legs back toward the floor. As the legs descend, the lever arm increases and the core demand grows. Maintain constant lower back contact with the mat throughout the entire descent.
Slow descent, back stays flatHover at the bottom
Stop the legs 5–10 cm above the floor — just before they would touch. This keeps constant tension on the core. If your back begins to arch before reaching this point, that is your current range of motion limit — stop there.
Stop just before the floorRepeat for reps
Immediately raise the legs again for the next rep without resting on the floor. Maintain rhythmic breathing and consistent pace. Terminate the set the moment the lower back peels off the mat — quality over quantity.
No rest on the floor between repsCommon mistakes
What goes wrong — and why
Lower back arching off the mat
When the hip flexors are stronger than the abs, they pull the pelvis into anterior tilt, causing the lumbar spine to lift off the mat. This transfers the load from the abs to the hip flexors and can compress the lumbar discs.
Reduce the range of motion. Lower the legs only to the angle where your back stays flat. Over weeks, as the lower abs strengthen relative to the hip flexors, the range will increase safely.
Dropping the legs fast
Allowing gravity to drop the legs removes the eccentric loading that makes the exercise effective. The descent is where much of the strengthening occurs.
Count 3–4 seconds during the lowering phase. The down phase should feel harder than the lift.
Holding the breath
Holding the breath during the hardest part of the rep (legs near the bottom) increases intra-abdominal pressure but reduces the oxygenation needed to complete quality reps.
Inhale as legs lower, exhale as legs rise. Establish this breath pattern before adding reps — it will also help you maintain core tension through the full range.
Variations · Progressions · Regressions
Adaptations for every level
Bent-Knee Leg Raise
Perform the same movement with knees bent at 90°. The shorter lever arm dramatically reduces the demand on the lower abs and hip flexors, making it appropriate for beginners who cannot keep the lower back flat with straight legs.
Flutter Kicks
Raise both legs to 45° then alternate rapid small kicks up and down. Maintains continuous tension on the core and adds a hip flexor endurance component. Excellent for conditioning.
Hanging Leg Raise
Hang from a pull-up bar and raise straight legs to horizontal or above. The absence of a mat to press against means the core must create all the spinal stability unassisted — dramatically harder than the lying version.