3-4 Sit-up

How to do the 3-4 Sit-up

1. 1Lie on your back on the floor or a mat with your knees bent and feet flat, roughly hip-width apart.
2. 2Cross your arms over your chest or rest your fingertips lightly at the sides of your head without pulling on your neck.
3. 3Brace your core and press your lower back gently into the floor to remove any slack.
4. 4Curl your torso up smoothly, leading with your chest and lifting through your abs rather than yanking your head forward.
5. 5Rise to roughly three-quarters of a full sit-up, until your torso is at about a 45–60° angle and your abs are fully contracted.
6. 6Pause briefly at the top and squeeze your abdominals without letting your lower back round excessively.
7. 7Lower under control back toward the floor, stopping just before your shoulder blades fully relax to keep tension on the abs.
8. 8Complete your reps, then rest your back flat on the floor.

Form tips

• Move slowly on the way down — the lowering phase is where much of the ab tension is built.
• Keep your chin a fist's width from your chest so your neck stays neutral and your abs do the work.
• Exhale as you curl up and inhale as you lower to help brace the core.
• Keep your feet flat and stable; if they lift, tuck them under a stable object rather than swinging your legs.
• Stop the rep at three-quarters rather than sitting all the way up to keep load on the abs instead of the hip flexors.

Common mistakes

• Pulling on the back of your head or neck to lift, which strains the cervical spine and shifts work away from the abs.
• Using momentum to swing up, which removes tension from the rectus abdominis and reduces the training effect.
• Sitting all the way upright every rep, which hands much of the work to the hip flexors instead of the abs.
• Letting the lower back arch off the floor on the way down, which loses core bracing and can stress the spine.

Frequently asked questions