Reclined Jackknife Crunch
The Reclined Jackknife Crunch is a compound exercise that mainly works the core, with help from the hip adductors (inner thighs). No equipment needed: it uses just your bodyweight.
Optional Equipment
Reclined Jackknife Crunch Muscles Worked
Primary
Abdominals (rectus abdominis)
Secondary
Obliques; Hip Adductors
How to do the Reclined Jackknife Crunch
Setup
Begin seated on your exercise mat, leaning back slightly onto your forearms to support your upper body.
Keep one leg bent while the other remains extended straight in front of you.
Movement
Exhale and simultaneously bring the extended leg toward your chest while lifting the opposite arm to reach for your foot or shin.
Your upper body should crunch upward slightly as the arm and leg meet in a diagonal motion.
Slowly lower your arm and leg back to the starting position without letting them touch the floor completely if possible to maintain core tension.
Alternate legs after completing the desired number of repetitions for one side, or switch legs on each rep.
Reclined Jackknife Crunch FAQs
What muscles does the Reclined Jackknife Crunch work?
The Reclined Jackknife Crunch mainly works the core, with help from the hip adductors (inner thighs). The main muscles are the rectus abdominis.
What equipment do you need for the Reclined Jackknife Crunch?
None. The Reclined Jackknife Crunch is a bodyweight exercise, so you can do it anywhere.
Is the Reclined Jackknife Crunch a compound exercise?
Yes. It's a compound movement, meaning it trains several muscle groups at once rather than isolating one.
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