3/4 Sit-Up
The 3/4 sit-up is a standard sit-up with the bottom quarter removed: you come up to vertical, then lower only three quarters of the way before starting the next rep. Stopping short keeps constant tension on the abs and takes the hip flexors and lower back out of the equation, which is exactly why it is worth doing over a full sit-up.
Own the movement
Set up first, then execute. Every cue below is something you can check on your next set.
Before the first rep
- Lie on your back with knees bent at roughly 90 degrees and feet flat on the floor.
- Secure your feet under something solid, or have a partner hold them, so you are not fighting to stay anchored.
- Place your hands lightly at the sides of your head — fingertips by your ears, not laced behind your skull.
- Flatten your lower back into the floor and take the slack out of your abs before the first rep.
Every rep
Breathing & tempo — Exhale as you curl up, inhale on the way down. Two seconds up, two seconds down, no pause at the bottom because there is no bottom.
Before you load it
- If you have a history of lower-back problems, an anti-extension exercise like a plank or a dead bug is usually a better choice than any loaded spinal flexion.
Sets, reps & load
Where to start, and what to change when it stops being hard.
Bodyweight is the starting point. When 20 controlled reps stop being challenging, hold a 5-10 kg plate across your chest rather than pushing the rep count into the thirties — the abs respond to load like any other muscle.
What goes wrong
The errors that show up most often, and the cue that fixes each one.
Rest your fingertips by your ears and keep your elbows in your peripheral vision. If your neck is sore afterwards, your arms did the work.
Stop when your shoulder blades are about to touch. The whole point of the movement is the quarter you leave out.
Curl the spine segment by segment. Slow the tempo to two seconds up and two down — if you cannot, the tempo was hiding a lack of control.
Once you can clear 20 clean reps, add load — hold a plate on your chest — or slow the tempo rather than adding more reps.
Why bother
In a normal sit-up the hardest part is peeling your shoulders off the floor, and that portion is driven heavily by the hip flexors rather than the abs. Resting your back flat at the bottom also gives the abs a moment off on every rep.
Cutting the last quarter of the descent removes both problems. The abs never fully release, the hip flexors contribute less, and a set that used to be about rep count becomes about time under tension. Most people find their honest rep count drops by a third the first time they try it properly.
Where it fits
End of a session, as accessory work — two or three sets. This is a trunk flexion movement, so pair it with an anti-extension hold like a plank and something rotational rather than doing three variations of the same crunch.
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
When this gets easy
Asked and answered
Why not just do a full sit-up?
A full sit-up rests the abs at the bottom of every rep and leans harder on the hip flexors to start the next one. The 3/4 version keeps tension constant and keeps the work in the abs. Same movement, better stimulus per rep.
Will this give me visible abs?
It will build them; whether you can see them is a body-fat question, not a training one. No amount of sit-ups burns fat off your midsection specifically. Train the abs for strength, and handle definition through your overall calorie balance.
My neck hurts. What am I doing wrong?
Almost certainly pulling on your head with your hands. Move your fingertips to the sides of your head so they cannot pull, keep a fist of space under your chin, and drop the rep count until your abs can do the work unaided.
How many should I be doing?
Three sets of 10-20 clean, slow reps is plenty as accessory work. If you are hitting 30 easily, the movement has become endurance work — add a plate to your chest instead.