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Jackknife Sit-Up

Jackknife Sit-Up

Target Muscle Groups
abs muscle group imageMain

Abs

upper_legs muscle group image

Upper Legs

Equipment
body equipment exampleMain

Body Weight

Difficulty

intermediate

Exercise Type

strength

Log Type

reps

Instructions

The Jackknife Sit-Up is an effective exercise that targets the core, including the rectus abdominis and obliques, as well as engaging the hip flexors. This exercise combines elements of both a sit-up and a leg raise, providing a challenging and comprehensive core workout. Here’s how to perform the movement correctly: Starting Position: Lie flat on your back on an exercise mat. Extend your arms straight back behind your head, keeping them close to your ears. Extend your legs straight out in front of you, keeping them close together. Execution: Tighten your core muscles to prepare for the movement. Lift your arms and legs simultaneously, bringing them towards each other. Aim to touch your hands to your feet or shins at the top of the movement. Exhale as you lift your arms and legs. Top Position: At the peak of the movement, your body should form a "V" shape, with your arms reaching towards your feet and your legs lifted off the ground. Hold this position briefly, ensuring your core is fully engaged. Returning to Start: Slowly lower your arms and legs back to the starting position, maintaining control throughout the movement. Inhale as you lower your arms and legs.

Explore by Muscle

abs group image

Abs

back group image

Back

biceps group image

Biceps

cardio group image

Cardio

chest group image

Chest

forearms group image

Forearms

glutes group image

Glutes

shoulders group image

Shoulders

triceps group image

Triceps

upper_legs group image

Upper Legs

lower_legs group image

Lower Legs

Explore by Equipment

body group image

Body Weight

bands group image

Bands

barbell group image

Barbell

bench group image

Bench

dumbbell group image

Dumbbell

exercise_ball group image

Exercise Ball

ez_curl_bar group image

EZ Curl Bar

foam_roll group image

Foam Roll

kettlebell group image

Kettlebell

machine_cardio group image

Cardio Machine

machine_strength group image

Strength Machine

pullup_bar group image

Pullup Bar

weight_plate group image

Weight Plate

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Crunch with Hands Overheadbanner

Crunch with Hands Overhead

Seated Leg Tuckbanner

Seated Leg Tuck

Cable Upward Chopbanner

Cable Upward Chop

Abdominal Pendulumbanner

Abdominal Pendulum

Side Bridgebanner

Side Bridge

Bench Crunchbanner

Bench Crunch

Machine Ab Crunchbanner

Machine Ab Crunch

Alternating Heel Touchbanner

Alternating Heel Touch

Dragon Flagbanner

Dragon Flag

Side Plankbanner

Side Plank

Stability Ball Hamstring Stretchbanner

Stability Ball Hamstring Stretch

Sun Salutationbanner

Sun Salutation

Hanging Knee Raisebanner

Hanging Knee Raise

Stability Ball Incline Ab Crunchbanner

Stability Ball Incline Ab Crunch

Sage Twist 1banner

Sage Twist 1

Standing Opposition Reachbanner

Standing Opposition Reach

Downward Facing Dog Single-Legbanner

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Cable Reverse Wood Chopbanner

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Medicine Ball Two-Arm Overhead Throwbanner

Medicine Ball Two-Arm Overhead Throw

Side Plank Crunchbanner

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Straight Arm Plankbanner

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Crow Posebanner

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Kettlebell Bent Pressbanner

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Weight Plate Russian Twistbanner

Weight Plate Russian Twist

Table Posebanner

Table Pose

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Decline Bench Leg Raise with Hip Thrust

Bench Jackknife Sit-Up banner

Bench Jackknife Sit-Up

Reach and Catchbanner

Reach and Catch

Rollingbanner

Rolling

Bow Posebanner

Bow Pose

Wide Leg Stretchbanner

Wide Leg Stretch

Bench Leg Raise (Supine)banner

Bench Leg Raise (Supine)

Stability Ball Single-Leg Bridgebanner

Stability Ball Single-Leg Bridge

Cross Body Crunchbanner

Cross Body Crunch

Cable Upward Chopbanner

Cable Upward Chop

Mountain Climberbanner

Mountain Climber

Cable Knee Raise (Supine)banner

Cable Knee Raise (Supine)