Jackknife Sit-Up

BeginnerBody onlyCompoundPullStrength
Jackknife Sit-Up — start position
Jackknife Sit-Up — end position

How to do it

  1. Lie flat on the floor (or exercise mat) on your back with your arms extended straight back behind your head and your legs extended also. This will be your starting position.
  2. As you exhale, bend at the waist while simultaneously raising your legs and arms to meet in a jackknife position. Tip: The legs should be extended and lifted at approximately a 35-45 degree angle from the floor and the arms should be extended and parallel to your legs. The upper torso should be off the floor.
  3. While inhaling, lower your arms and legs back to the starting position.
  4. Repeat for the recommended amount of repetitions.

Muscles worked

Primary:Abdominals

Programming this lift? The warm-up calculator builds your ramp, and the 1RM calculator sets your percentages.

More abdominals exercises

All abdominals exercises →

This is one card in your program builder

Trainers on AirFit drag movements like this into programs — demo media included — and clients follow them and log sets in AirFit on iOS, Android or the web. Lifters: AirFit Coach can program it for you, or find a human coach.