The hanging straight leg raise is one of the most demanding bodyweight exercises for the hip flexors and lower abdominals. Performed by hanging from a pull-up bar and raising the straight legs toward the horizontal or beyond, it requires a combination of hip flexor strength, core anti-extension stability, and grip endurance that most people significantly underestimate before attempting it.
The straight leg version is meaningfully different from the more common hanging knee raise, and understanding this difference determines whether the exercise is appropriate for someone’s current strength level and what the appropriate progressions look like.
How Hanging Straight Leg Raises Differ From Hanging Knee Raises
The hanging knee raise is the more accessible version, where the knees are drawn toward the chest with the knees bent. The straight leg raise extends the knees throughout the movement, maintaining the full length of the leg as a lever.
The mechanical consequence:
By keeping the knees extended, the straight leg raise significantly increases the moment arm from the hip joint to the centre of mass of the leg. A longer moment arm means a greater torque must be produced by the hip flexors to lift and control the legs. Research and biomechanical analysis consistently shows the straight leg raise to be substantially more demanding than the bent-knee version for the same degree of hip flexion.
The consequence for training:
Someone who can comfortably perform 15 hanging knee raises may find the straight leg version extremely difficult to perform with correct technique. The prerequisite strength for the straight leg version is significantly higher, and attempting it before the base is established typically results in the lumbar swinging compensation that is the most common and most consequential error in this exercise.
Muscles Targeted
Primary:
- Iliopsoas (psoas major and iliacus): The primary hip flexors driving the leg upward throughout the range
- Rectus femoris: Contributes to hip flexion alongside its role in knee extension (holding the knee straight throughout)
- Lower rectus abdominis: Works eccentrically to control the pelvic position and concentrically during leg raising in the upper range
Secondary:
- Tensor fascia latae: Assists with hip flexion in the early range
- Core (anti-extension): The entire anterior core works to prevent the lumbar spine from extending as the legs are raised
- Grip and forearm muscles: Hold the body on the bar throughout the set
- Shoulder and scapular stabilisers: Maintain the hanging position throughout
Why this is not primarily a core exercise:
The hanging straight leg raise is frequently described as a core exercise. While the core is significantly involved, the primary movement is hip flexion and the primary movers are the hip flexors. The core’s role is anti-extension stabilisation (preventing the lower back from arching) rather than the primary driving of the movement. This distinction matters for exercise selection: the hanging straight leg raise primarily develops hip flexor strength, with core stability as a secondary but significant demand.
Prerequisites
Attempting the hanging straight leg raise without adequate prerequisite strength typically results in the swinging and lumbar arching pattern that reduces the exercise’s effectiveness and increases injury risk. The following prerequisites should be met before the full straight leg version is attempted.
Grip strength: The ability to dead hang from a pull-up bar for at least 30 to 45 seconds without significant difficulty. If grip is the limiting factor during hanging leg raises, the exercise cannot be performed with sufficient control.
Hanging knee raise proficiency: The ability to perform 12 to 15 strict hanging knee raises (knees drawn to chest level, no swinging, controlled lowering) indicates sufficient grip strength and initial hip flexor strength for the straight leg progression.
Hip flexor strength in the supine position: As covered in the hip flexion exercises article on this site, the ability to perform 15 straight leg raises from the floor with a flat lumbar spine indicates the hip flexor strength needed for the straight leg hang version.
Core anti-extension stability: As covered in the isometric core exercises article on this site, the dead bug and hollow body hold develop the anti-extension core stability that prevents the lumbar arching during hanging leg raises. Proficiency with these exercises indicates readiness for the loaded hip flexion of the hanging version.
Step-by-Step Technique
The Hang
- Grip the bar with both hands, shoulder-width apart, in an overhand grip (palms facing away from the body)
- Allow the body to hang fully from the bar with the arms extended
- The body should be relatively still: eliminate any swinging from the outset
- Engage the core gently: draw the lower abdomen in slightly and maintain this throughout
- Retract the shoulder blades slightly (pull them down and back) to create a stable shoulder position rather than hanging passively on the shoulder joint
Grip options:
- Overhand (pronated): The standard grip. Develops grip strength and forearm endurance.
- Neutral grip (palms facing each other, if the bar allows): Often more comfortable for the wrists and elbows and may allow longer sets.
- Underhand (supinated): Changes the bicep involvement and may feel stronger for some people.
Overhand grip is recommended as the standard for most people.
The Lift
- From the dead hang, begin raising the legs by flexing the hips
- Keep the knees fully extended throughout: this is the defining technical requirement of the straight leg version
- Raise the legs until they are horizontal (parallel to the floor) for the standard version
- For the advanced version, continue raising the legs toward vertical or beyond
- The movement should be smooth and controlled rather than rapid
What should initiate the movement: The hip flexors should initiate the lift. The legs should rise smoothly from the hips rather than starting with a swing or a momentum-driven kick. In the first few degrees of the lift, focus entirely on the hip flexors contracting rather than on the legs moving.
The Hold (Optional)
At the top position, holding the legs horizontal or above horizontal for 1 to 2 seconds:
- Eliminates the possibility of using momentum from the downswing
- Increases the isometric hip flexor demand at the end range
- Provides visual confirmation of the correct end position
The hold is optional for beginners but recommended as technique becomes established.
The Lowering Phase (Eccentric)
- Lower the legs slowly under control, taking 2 to 3 seconds
- The hip flexors work eccentrically during the lowering phase
- Do not drop the legs rapidly: controlled lowering is as important as the lift for strength development
- Return to the full dead hang position before the next rep
- Re-establish the dead hang briefly before initiating the next lift
The pause between reps: A brief pause at the bottom (1 second) ensures the next rep begins from a controlled starting position rather than using the momentum of the downswing to assist the next lift.
Key Technique Cues
No lumbar swing: The most critical cue. The lower back should not arch significantly as the legs are raised. Any arching of the lumbar spine shifts the exercise from a hip flexor exercise to a lumbar extensor exercise and can produce lower back stress under the significant loading of the hanging position. If the lower back arches, the core is not controlling the pelvis and the exercise is beyond the current strength level.
Posterior pelvic tilt during the lift: As the legs are raised, think of tucking the pelvis slightly under (posterior pelvic tilt) rather than allowing the pelvis to tip forward (anterior pelvic tilt). This pelvic tuck engages the lower abdominals and maintains the lumbar spine in a neutral or slightly flexed position.
Knees locked throughout: Any bending of the knee reduces the lever arm and makes the exercise significantly easier. If the knees are bending, the hip flexor strength for the full straight-leg version is not yet adequate.
Shoulders engaged: The shoulder blades should be retracted and depressed (pulled back and down) rather than shrugged upward. Passive hanging on the shoulder joint creates excessive shoulder joint stress and reduces stability.
Feet together or hip-width: Keeping the feet together or at hip-width (rather than allowing them to separate widely) maintains the correct alignment and prevents the legs from swinging outward for momentum.
Common Errors and Fixes
Error 1: Lumbar Swing (The Most Common and Most Important Error)
What it looks like: As the legs are raised, the lower back arches significantly and the whole body swings forward and backward. Rather than the legs moving upward from a stable trunk, the entire body rocks with each rep.
Why it happens: The hip flexors and core are not strong enough to raise the straight legs without the lumbar extensors compensating, and the swinging creates momentum that assists the lift.
Why it matters: The swinging pattern trains the lumbar extensors and momentum rather than the hip flexors, and the repeated lumbar extension under the significant body weight load of the hanging position creates unnecessary lower back stress.
Fix: Regress to the hanging knee raise or the floor-based straight leg raise until sufficient strength is developed. When returning to the straight leg version, begin with only 3 to 5 reps performed with deliberate focus on preventing any lumbar arch or swing. Use a mirror or video to verify the lumbar position.
Error 2: Bending the Knees During the Lift
What it looks like: The knees bend as the legs are raised, converting the exercise into a hanging knee raise.
Why it happens: The hip flexor strength for the full straight-leg version is insufficient, so the body finds the easier position.
Fix: Actively contract the quadriceps before initiating the lift. Think of locking the knees by tensing the thigh muscles. Reduce the rep target to 3 to 5 and focus on maintaining locked knees through the full range.
Error 3: Using Momentum and Swinging
What it looks like: The athlete swings the legs forward using momentum from a backward swing rather than muscular contraction.
Fix: Come to a complete stop between each rep. If swinging persists, introduce a 2-second pause between each rep to eliminate any residual momentum.
Error 4: Not Reaching Horizontal
What it looks like: The legs are raised only to 30 to 45 degrees from vertical (which is 45 to 60 degrees below horizontal) rather than to the horizontal target.
Why it matters: Below the horizontal position, the hip flexors are working in a mechanically advantageous position against gravity. Above horizontal, the demand increases significantly. Most of the training stimulus is in the upper portion of the range.
Fix: Set a target height (the wall in front, a marker on the ceiling) to cue the correct end position. Reduce the reps and focus on reaching the target height.
Error 5: Passive Shoulder Hanging
What it looks like: The shoulders are shrugged up toward the ears (passive shoulder elevation) rather than retracted.
Fix: Before initiating each set, consciously pull the shoulder blades down and back. This creates shoulder joint stability and is a safety consideration for shoulder health during any hanging exercise.
Progressions
Regression 1: Floor Straight Leg Raise
As covered in the hip flexion exercises article on this site, the floor straight leg raise develops the same hip flexor muscles in a position where gravity is less challenging and the lumbar spine is supported by the floor. This is the appropriate exercise when the hanging version is not yet achievable.
Regression 2: Hanging Knee Raise
Bring the knees to the chest with knees bent. Develops the grip strength, core stability, and initial hip flexion strength needed for the straight leg version.
Progression criterion: 3 sets of 15 with fully controlled lowering and no swinging.
Level 1: Hanging Straight Leg Raise to 45 Degrees
Raise the straight legs to 45 degrees from vertical (45 degrees short of horizontal) rather than to horizontal. This partial range is significantly easier than horizontal but develops the correct pattern.
Sets and reps: 3 sets of 8 to 10
Level 2: Hanging Straight Leg Raise to Horizontal
The standard version, raising the legs to parallel with the floor (90 degrees of hip flexion).
Sets and reps: 3 sets of 8 to 10
Level 3: Hanging Straight Leg Raise With Hold
Add a 2 to 3 second hold at the horizontal position. This eliminates momentum assistance and significantly increases the isometric hip flexor and core demand at end range.
Sets and reps: 3 sets of 6 to 8
Level 4: Hanging Straight Leg Raise to Vertical (L-Sit Position)
Raise the straight legs until they are vertical (perpendicular to the body, pointing directly upward). This requires significantly more hip flexor strength than the horizontal version.
Sets and reps: 3 sets of 5 to 8
Level 5: Hanging Toes to Bar
Raise the straight legs until the toes touch or approach the bar. This requires near-complete hip flexion (approximately 150 to 160 degrees) and is the most demanding version of the exercise. A degree of posterior pelvic tilt and spinal flexion is inherent in the toes-to-bar position.
Sets and reps: 3 sets of 5 to 8
Level 6: Weighted Hanging Straight Leg Raise
Attach ankle weights or hold a light dumbbell between the feet to add external resistance to any of the levels above.
Sets and reps: 3 sets of 6 to 8
Programming the Hanging Straight Leg Raise
As a primary hip flexor exercise:
The hanging straight leg raise can serve as the primary hip flexor strengthening exercise when gym equipment is limited or when the hanging demands (grip, shoulder stability) provide additional training benefit alongside the hip flexor development.
3 sets of 8 to 10 reps, 2 to 3 times per week.
As part of a pull-up bar circuit:
The hanging straight leg raise pairs naturally with pull-ups and hanging knee raises in a pull-up bar circuit:
- Pull-ups: 3 x 8
- Hanging straight leg raise: 3 x 8
- Dead hang: 3 x 20 seconds
As an accessory exercise to lower body training:
2 to 3 sets of 8 to 10 at the end of a lower body session, when the exercise provides a hip flexor stimulus complementary to the hip extension work of deadlifts and hip thrusts.
Frequency: 2 to 3 times per week is appropriate. The hip flexors recover relatively quickly from the hanging version (compared to the grip and shoulder demands), so frequency can be higher if grip recovery allows.
Grip fatigue management: If grip fails before the hip flexors are fatigued, use chalk or lifting straps on the final sets. Alternatively, use a pull-up bar with thicker grips that develop grip strength specifically, or introduce dedicated grip strengthening work alongside the hanging leg raise programme.
Frequently Asked Questions
How is the hanging straight leg raise different from the captain’s chair leg raise?
The captain’s chair (Roman chair) provides forearm and back support, eliminating the grip and shoulder stability demands of the hanging version. Because the arms and back are supported, the captain’s chair version is generally more accessible and allows more reps. The hanging version provides an additional grip and shoulder stabilisation stimulus that the captain’s chair does not. Both target the hip flexors and core similarly in terms of the leg-raising movement.
Should I feel hanging straight leg raises in my abs or my hip flexors?
You should feel both, with the hip flexors as the primary sensation in the anterior hip and groin, and the lower abdominals working to control the pelvic position. If the feeling is predominantly in the lower back, lumbar compensation is occurring and the exercise should be regressed. If the abs are cramping but the hip flexors feel relatively easy, the hip flexors may not be contracting correctly and the movement may be driven more by the trunk than the hip.
Why do I feel hanging leg raises in my lower back?
Lower back sensation during hanging leg raises indicates lumbar extension compensation: the lower back is arching to help lift the legs rather than the hip flexors doing the work cleanly. This is the most important error to address. Regress to floor straight leg raises and hanging knee raises until the hip flexors are strong enough to lift the straight legs without lumbar compensation.
How do I build up to hanging straight leg raises if I cannot do them yet?
Follow the regression and progression pathway: build dead hang time to 45 seconds, achieve 3 sets of 15 hanging knee raises, build floor straight leg raises to 3 sets of 15 with flat lumbar spine, then attempt the hanging straight leg version at partial range (45 degrees) before progressing to the full horizontal version.
Can hanging straight leg raises replace cable or machine hip flexion exercises?
The hanging version develops the hip flexors against the weight of the full leg (a fixed load determined by body weight) while cable machines allow progressive loading beyond body weight. For bodyweight training contexts, the hanging straight leg raise is the most demanding available hip flexor exercise. For athletic contexts where maximum hip flexor strength is the goal, the hanging version should be complemented by cable hip flexion as progressive loading becomes necessary.