Cable Reverse Crunch
A floor reverse crunch with ankle straps attached to a low pulley, so the abs fight a constant pull instead of only gravity. You lie with knees bent at 90 degrees and roll the pelvis toward your ribs, lifting the hips a few centimetres — the cable keeps tension on at the bottom, where a bodyweight reverse crunch goes slack.
Own the movement
Set up first, then execute. Every cue below is something you can check on your next set.
Before the first rep
- Ankle strap on the lowest pulley. Put a mat down before you attach anything or you will end up crawling for it later.
- Sit with your feet toward the tower, buckle both ankles, then lie back and shuffle away until the stack is already lifted.
- Bend the knees to a fixed 90 degrees and hold that angle for the whole set — the knee joint does not move in this exercise.
- Check the cable runs in a straight line with your shins. If it angles up or down, move the pulley a notch, not your body.
- Hands behind your head or flat beside your hips, whichever stops you pulling with your arms.
Every rep
Breathing & tempo — Exhale hard as the hips lift — a forced exhale helps the pelvis tilt. Inhale on the way down. One second up, one second held, three seconds down.
Sets, reps & load
Where to start, and what to change when it stops being hard.
Start at the lightest plate on the stack, usually 5 kg. The abs are working against a long lever here, so honest loads stay low for a long time. Good looks like a one-second pause at the top with the hips genuinely off the mat. Add weight only when you can hold that pause on the final rep of the final set; before that, add a second to the lowering phase instead.
What goes wrong
The errors that show up most often, and the cue that fixes each one.
Stop the rep the moment your hips leave the floor and hold there. Range beyond that comes from the hip flexors, not the abs — measure the rep in centimetres of hip lift, not in knee travel.
Shuffle further from the tower at setup so the stack is lifted even in the reset position. If the plates touch down at the bottom, you are 15 centimetres too close.
Keep the pelvis tucked and finish the descent early — stop when the ribs want to flare. If your back still arches, halve the weight and shorten the lowering range.
Put your palms flat on the floor beside your hips instead. If you cannot complete reps without hauling on your neck, the load is set too high.
Why bother
A bodyweight reverse crunch loses all resistance once your knees pass over your hips — gravity stops helping and the bottom of the movement is free. Running an ankle strap to a low pulley keeps the abs loaded through the whole range, including the reset position, which is exactly where most people rest without noticing.
The range is smaller than it looks. Useful travel is the pelvis tilting backwards and the hips lifting perhaps five to ten centimetres off the mat. Everything beyond that is your knees swinging toward your face on hip-flexor power, and it adds nothing to the abs.
Where it fits
Late in a session, two or three times a week, once the machine is free — this is a setup-heavy movement and not worth queueing for. Pair it with a top-down flexion movement like a cable crunch: this one loads the lower fibres from the pelvis end, that one from the ribcage end.
If this one isn't it
No kit, too hard, or too easy — here's where to go instead.
Same job, different kit
Start here instead
Asked and answered
Does this hit the lower abs specifically?
Partly. The rectus abdominis is one sheet and contracts along its length, so you cannot isolate a bottom half. What you can do is bias which end moves: the pelvis moving toward a fixed ribcage does load the lower fibres somewhat harder than a standard crunch. Treat it as a bias, not a separate muscle.
The setup is a hassle. Is it worth it over a hanging leg raise?
If you can hang, the hanging leg raise is the better exercise — longer range, no strap fiddling, and grip work for free. The cable version wins when your grip fails before your abs, when you want a load you can dial in by 5 kg increments, or when you cannot control the swing while hanging.
Why do I feel this in my hip flexors instead of my abs?
Because you are moving the legs rather than the pelvis. The hip flexors run from the femur to the lumbar spine and will happily do the whole job if you let the range get long. Cut the rep short: pelvis tilts, hips lift a hand's width, stop. If it still goes to the hips, drop the weight and start each rep with a hard exhale.
My gym has no ankle straps. What can I use instead?
Thread a nylon lifting strap or a short resistance band through the carabiner and loop it over both shins. It works, but the load now sits above the ankle joint, which shortens the lever and makes the same stack weight feel easier — expect to add a plate. The cleaner substitute is a decline reverse crunch with a light dumbbell squeezed between your feet: constant tension at the bottom, no strap hunt, and nothing digging into your ankle bones.