JackKnife
Expert Advice
Control the movement both on the way up and down to maximize muscle engagement and prevent momentum from taking over.
How-to-do Steps
- Lie flat on your back with your arms extended behind your head and legs straight.
- Simultaneously lift your arms and legs up, reaching towards each other in a 'V' shape.
- Try to touch your toes with your fingertips at the top of the movement.
- Slowly lower your arms and legs back to the starting position without letting them touch the floor.
- Repeat for the desired number of repetitions.
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Muscles Worked
JackKnife primarily targets the Quads, Abs, Hamstrings, Calves, Glutes, Chest, Lats, with Stretching mechanics using Body Weight. Understanding muscle activation patterns helps you focus on proper engagement and maximize training effectiveness.
Primary
Quads14%
Abs14%
Hamstrings14%
Calves14%
Glutes14%
Chest15%
Lats15%
Equipment
Body Weight
Exercise Type
Stretching
Sets & Reps Guidance
Beginner3 x 20s
Intermediate3 x 30s
Advanced4 x 45s
Frequently Asked Questions
What muscles does JackKnife work?
JackKnife primarily targets the Quads, Abs, Hamstrings, Calves, Glutes, Chest, Lats. It is classified as a Stretching exercise performed with Body Weight.
How many sets and reps should I do for JackKnife?
For beginners, start with 3 sets of 20s. Intermediate lifters can do 3 sets of 30s. Advanced athletes can push to 4 sets of 45s. Adjust based on your goals and recovery capacity.
Is JackKnife suitable for beginners?
JackKnife is rated as an advanced exercise and is best suited for experienced lifters. Beginners should build foundational strength with simpler movements first before attempting this exercise.
