Sit-ups

• Upper abs
• Intermediate
• Reps — 12 reps per set

The sit-up curls the whole trunk off the floor, vertebra by vertebra, from lying flat to sitting tall — a bigger range than the crunch.

The longer range recruits the hip flexors alongside the abs, which is fine when the abs lead the movement. Roll up smoothly instead of jerking; anchor discomfort in the neck or lower back means the abs quit and something else took over.

How to do it

1. Lie on your back with knees bent and feet anchored.
2. Curl your whole torso up until your chest meets your thighs.
3. Lower back down slowly to the start.

Breathing: Exhale on the way up.

Common mistakes

• Hauling against the anchored feet so the legs drag the torso upright.
• Twisting one shoulder toward the opposite knee once the reps get hard.
• Unclasping the hands and throwing the arms forward to reach the top.

Form tips

• Let the hands only cradle the head; the elbows must not drag the chin toward the chest.
• Peel the back off the floor one segment at a time rather than throwing the torso up.
• Lower all the way down under control instead of bouncing off the floor into the next rep.

Muscles worked

Alternatives with the same focus

• Frog Crunches
• Reach-Up Crunches
• 3/4 Sit-Ups

Where it appears in the 30-day plan

Programs in the app that schedule this movement:

• Core & Abs
• Upper Abs