Side Jackknifes

BodyweightIntermediateIsolationEach side
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Quick answer

Side Jackknifes is an intermediate isolation bodyweight exercise that mainly works the obliques, with the abs and quads assisting.

Written by the GymStreak coaching team

Muscles worked

Front
Back

Primary

Secondary

How to do Side Jackknifes

  1. 1

    Lie down on the floor on your left side with your legs lying on top of each other with your knees bent.

  2. 2

    Lightly place your right hand behind your head and your other arm on your abs. This is your starting position.

  3. 3

    Begin the movement by crunching up as you would in a normal crunch but focus on contracting your oblique muscles. Lift your right leg as you do this.

  4. 4

    Crunch as high as you can then after a brief pause, return to the starting position.

  5. 5

    Repeat the movement on the left side.

Form cues

  • Variation: you can use ankle weights to increase difficulty.
  • Don’t pull on your neck with your hands.
  • Perform the reps very slowly, don't rush it!.

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