GymPlan AIJackknife Sit-Up
Jackknife Sit-Up is a beginner compound bodyweight exercise that mainly works your abs.
💪 Abs🏋️ Bodyweight📈 Beginner🔗 Compound🎯 3 sets of 8-15 reps
How to do the jackknife sit-up
- 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.
- 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.
- While inhaling, lower your arms and legs back to the starting position.
- Repeat for the recommended amount of repetitions.
Muscles worked
Primary: Abs
Sets and reps
Do 3 sets of 8-15 controlled reps, stopping 1-2 reps before failure. When you can do 15 easily, slow the tempo or add weight.
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What muscles does the jackknife sit-up work?
It mainly works your abs.
How many sets and reps of jackknife sit-up should I do?
Do 3 sets of 8-15 controlled reps, stopping 1-2 reps before failure. When you can do 15 easily, slow the tempo or add weight.
Is the jackknife sit-up good for beginners?
Yes. It is a beginner-friendly movement: start light and focus on the form steps above.