Cable Crunches & Leg Raises: The Most Underrated Ab Exercises for Real Core Strength

When people think “abs,” the mind often jumps to sit-ups, crunches, planks, maybe Russian twists, or cable woodchops. Few consistently program cable crunches or leg raises (especially advanced versions). Yet these moves offer something most “traditional ab” exercises don’t: continuous tension, harder-to-cheat mechanics, and scalable progression.

In our view, cable crunches and leg raises deserve a place in every ab routine. They complement one another, with cable crunches hitting the rectus abdominis with resistance, while leg raises challenge both lower abs and hip flexor control. Combined, they offer a fuller stimulus to your core than relying on just crunches or planks alone.

Because you use weights/cables, you can gradually increase the load as your abs get stronger. You’re not stuck doing more reps forever - you can “level up” the resistance.

Unlike bodyweight crunches where tension falls off at one end of the movement, a cable keeps pulling through the entire arc, ensuring your abs stay engaged.

The mechanics are such that you can hone in on spinal flexion rather than hip flexion. It isolates more to your “ab crunch” movement rather than just lifting your legs.

You can get a deeper “crunch” (more flexion) than many floor crunches. You can also vary angle, grip, or position to emphasize different parts of the abs or obliques.

Because you’re bracing against a load, there’s less room for using momentum (if you control the descent). Good form makes the difference.

If you train at home without a cable stack, this may not be available.

A common mistake is letting your arms pull the rope down, or using your lats/back to help. The bend has to come from your abs, not your upper body or arms.

If you don’t maintain control, over-extend, or arch the back, you can stress the lumbar region. Also, if you load too aggressively without good core stability, the spine may take unwanted load.

Standard cable crunches tend to emphasize the upper and mid-rectus, unless you adjust movement or combine with other movements. You may not fully fatigue lower abs with just cable crunches

Heavy cable work might start making your grip, shoulders, or arms tired, which could limit your ability to sustain ab focus

Leg raises force your lower rectus abdominis and the stabilizers to resist hip flexion and control the descent. That’s a region harder to hit in many ab exercises.

Some leg raises require only a bar or a captain’s chair. Others (lying ones) need just floor space. Great for home use.

Because the movement involves resisting torque and controlling a long lever (the legs), your core must stabilize strongly.

You can start with bent-knee raises, then straight-leg raises, then hanging raises, then weighted raises.

Strengthening lower-core and hip flexor control helps posture and can reduce risk of lower back issues.

One frequent critique is that leg raises may shift load toward the hip flexors (like iliopsoas) more than the abs, especially when done poorly. Especially at the bottom end. Some argue that unless you “crunch” the pelvis at the top, the movement is more hip flexion than true abdominal flexion.

If your lower back arches or comes off the floor (in lying versions), you risk compressing the lumbar spine. The descent is often where back strain occurs.

Once your core is fatigued, your pelvis may tilt, lower back may arch, or you may start swinging the legs - which reduces effectiveness and increases injury risk.

Bodyweight may become too easy after a point. You’ll need to add weight or progression (ankle weights, hanging versions, etc.).

Some trainers and anatomy critics argue that leg raises fundamentally are hip flexor movements, and that the rectus abdominis is more a stabilizer in many forms. Still, many practitioners retain leg raises as a valuable tool, but with caution and good coaching

This is the go-to version in most gyms.

Setup & Execution:

• Attach a rope (or appropriate bar) to a high pulley on a cable machine.
• Kneel facing the machine, so that the rope hangs down behind your head (so when you grab it, your hands are by your ears/neck).
• Grab the rope with both hands (palms facing in, thumbs up or neutral grip), keeping elbows tucked in slightly.
• Brace your core, glutes engaged. Slightly posterior tilt your pelvis (tuck your pelvis under) so your lower spine isn’t over-arching.
• Exhale, crunch downward by flexing your spine: bring your elbows down toward your thighs (or knees) in a controlled arc. Focus on using your abs, not pulling with your arms.
• Pause / squeeze at the bottom.
• Inhale, slowly return (extend) your torso back to near start (not fully upright with arch). Resist, don’t let the cables yank you back.
• Repeat for the prescribed reps.

• Don’t let arms “steal” the motion. Elbows should stay relatively fixed - the hands don’t pull.
• Avoid excessive range, don’t bend too far or hyperflex.
• Control the return. Don’t let the weight slam you back.
• Keep your core braced, don’t let lower back “give up.”
• Keep hips stable, don’t rock or shift.

• Standing cable crunch: Same principle, but you stand instead of kneel. Adds balance component, though you may not be able to load as heavily.
• Kneeling oblique cable crunch: Crunch toward one knee (elbow to knee) to target side/oblique fibers.
• Tempo cable crunch: Slow down both the crunch and return (3–5 seconds each way) to amplify time under tension.
• Resistance band cable crunch: If no cable machine, anchor a band overhead and simulate the same motion. (Less smooth tension, but workable.)

There are several forms of leg raises. I'll walk from easiest to hardest.

• Lie flat on your back on a mat. Hands can be placed under your glutes for lumbar support or by your sides.
• Engage your core; press your lower back lightly into the floor.
• Lift both legs up toward vertical (or as high as your flexibility allows), keeping them straight (or slightly bent if needed).
• Pause briefly at the top (squeeze core).
• Slowly lower legs back down, but stop a few inches above the ground, don’t let them slam down. Maintain tension.
• Repeat.

• Don’t let your lower back arch off the floor - that’s a cue you’re letting the back, not abs, take over.
• Go slow on the descent - the negative is really important.
• If straight leg raises are too tough, bend knees (knee raises) to reduce lever length.

• Use a captain’s chair vertical leg-raising station or parallel bars with back support.
• Forearms rest on pads, hands grip handles, back against support.
• Brace yourself, engage core.
• Lift knees/legs upward. Beginners raise knees; advanced do straight-leg.
• Squeeze at top.
• Lower under control.

• Knee raises (bend knees) - easier, less lever.
• Straight-leg raises - harder, more leverage.
• Weighted leg raises - hold ankle weights or add is resistance once bodyweight is easy.
• Twisting leg raises / oblique leg raises - add slight twist for obliques.

• Grip a pull-up bar (hands at shoulder width, overhand or neutral).
• Hang with core engaged (avoid full swing).
• Raise knees (bent) first, or straight legs if advanced.
• Bring legs up in front, ideally to parallel or higher.
• At the top, you can also tilt pelvis slightly (posterior pelvic tilt) to flex more. This is a subtle but powerful cue often emphasized by coaches.
• Lower slowly, resisting gravity.
• Repeat.

• Knee-up hanging raise (bend knees) good intro.
• Oblique hanging raise (twist at top) - for side core.
• Straight-leg + weight - for elite strength.

Because cable crunches and leg raises emphasize slightly different mechanics and parts of the abs, they go well together. Here’s a sample template:

• Start with bodyweight or lighter loads, prioritize form and control.
• Use tempo (slow eccentrics) to increase difficulty without dramatically increasing load.
• Gradually increase resistance on cable or add weight to leg raises.
• Mix oblique or twisting versions periodically to avoid adaptation.
• Allow recovery - strain from these exercises can linger; don’t crush abs every single day.

• You want to isolate the “ab crunch” movement with resistance.
• You want easier progressive loading.
• You want to reduce momentum cheating (if controlled).
• You find that floor or hanging leg raises aggravate your back (if cable gives more control).

• You want lower-abs / deep core / hip control emphasis.
• You prefer bodyweight movements or minimal equipment.
• You want a compound “lever challenge” rather than pure isolated crunch.
• You want to build functional strength that translates to other lifts / athletic movement.

In practice, combining both is often ideal.

• Lying bent-knee leg raises: 3 × 15 (slow)
• Cable crunch (light weight): 3 × 12;

• Hanging knee raises: 3 × 10
• Cable crunch (moderate): 3 × 12
• Cable oblique crunch (each side): 2 × 10

• Hanging straight-leg raises (or toes to bar): 3 × 8
• Heavy cable crunch: 3 × 8
• Weighted hanging or parallel bar leg raise (with ankle weights): 3 × 6
• Finish with slow tempo cable crunch (3s down, 1s squeeze, 3s up) × 8

Adjust sets/reps based on your recovery, fatigue, and program.

While we often obsess over form, sets, and reps, one thing people under-appreciate is hydration during workouts and cold recovery drinks. Here’s where the PROMIXX Pursuit Insulated shaker bottle becomes a compelling recommendation.

• Keeps your drink cold - the dual-wall vacuum-sealed stainless steel design helps maintain chilled temperature for hours. That’s refreshing during those heavy core sessions when you want cold recovery sips.
• Solid build & durability - stainless steel means less risk of cracking, warping, or flavor retention compared to plastic.
• Shaker functionality - good for mixing protein / recovery shakes cleanly (no clumps).
• Portability & everyday use - you can take it to the gym, carry it in your bag, and it’ll keep your liquids well insulated.

If you’re doing demanding core work, especially when breathing hard or sweating heavily, a cold, refreshing shake or electrolyte drink makes a difference in how you feel and recover. The PROMIXX Pursuit helps you keep that coolness, preventing your drink from warming up in your gym bag or studio.

Here’s a simple recipe to throw post-workout:

• 25-30 g whey (or plant) protein
• 1 scoop creatine (if you use it)
• 1 tablespoon natural peanut butter (or almond butter)
• 200 ml cold water + 100 ml milk (or milk alternative)
• A pinch of salt (for electrolytes)

1. Don’t overdo frequency - your abs need recovery. Two or three solid sessions per week is plenty.
2. Quality over quantity - better to do fewer reps with perfect control than many sloppy ones.
3. Mix it up - rotate variants, tempos, and grips so your core doesn’t adapt too soon.
4. Mind the rest of your program - strong abs help with posture, lifts, athletic performance, but they’re part of the system. Train your back, glutes, hips, etc.
5. Watch your breathing - exhale during the contraction (crunch) phase, inhale as you release.
6. Listen to your body - if a version causes lower-back pain, regress, adjust form, or reduce load.

Cable crunches and leg raises, used wisely, can bring a dimension to your core work many people skip. They’re not flashy, they don’t always get top-of-mind attention, but they work. And pairing them with good hydration (thank you, PROMIXX Pursuit) and recovery makes the whole process more sustainable.