Weight-Plate Jackknife Sit-Up
The Weight-Plate Jackknife Sit-Up is a compound exercise that mainly works the core. No equipment needed: it uses just your bodyweight.
Optional Equipment
Weight-Plate Jackknife Sit-Up Muscles Worked
Primary
Abdominals (rectus abdominis)
Secondary
Obliques; Hip Flexor (iliopsoas)
How to do the Weight-Plate Jackknife Sit-Up
Lie flat on your back on a mat holding a weight plate securely with both hands extended overhead.
Engage your core and simultaneously lift your straight arms and straight legs up toward each other.
Reach the weight plate toward your shins at the top of the movement while balancing on your tailbone.
Lower your arms and legs back down in a slow and controlled motion without touching the floor.
Inhale as you lower down and exhale forcefully as you crunch up into the jackknife position.
Weight-Plate Jackknife Sit-Up FAQs
What muscles does the Weight-Plate Jackknife Sit-Up work?
The Weight-Plate Jackknife Sit-Up mainly works the core. The main muscles are the rectus abdominis.
What equipment do you need for the Weight-Plate Jackknife Sit-Up?
None. The Weight-Plate Jackknife Sit-Up is a bodyweight exercise, so you can do it anywhere.
Is the Weight-Plate Jackknife Sit-Up 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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