Bodybuilding.com Information Motivation Supplementation
in:
Login or Create an account to set your gender preference.

Jackknife Sit-Up

Also Known As:

Exercise Data

Type: Strength
Main Muscle Worked: Abdominals
Equipment: Body Only
Mechanics Type: Compound
Level: Beginner
Sport: No
Force: Pull
Your Rating: 


8.7

Out of 10

Excellent

Exercise Rating Read Jackknife Sit-Up Reviews
SHARE Bookmark and Share


Jackknife Sit-Up Images

Jackknife Sit-Up
Click to enlarge
Jackknife Sit-Up
Click to enlarge




Jackknife Sit-Up Guide

Main Muscle: Abdominals

  1. Lie flat on the floor (or exercise mat) on your back with your arms extended straight back behind your head and your legs extended also. This will be your starting position.
  2. As you exhale, bend at the waist while simultaneously raising your legs and arms to meet in a jackknife position. Tip: The legs should be extended and lifted at approximately a 35-45 degree angle from the floor and the arms should be extended and parallel to your legs. The upper torso should be off the floor.
  3. While inhaling, lower your arms and legs back to the starting position.
  4. Repeat for the recommended amount of repetitions.

Variation: If you are really advanced you could use a medicine ball for added resistance.



Alternative Exercises For Jackknife Sit-Up

9.0

Out of 10

8.8

Out of 10

Butt-Ups

Muscle Targeted: Abdominals

8.5

Out of 10

Tips and Reviews - Login to rate

 





 
  • Reviews & Tips
  • Reviews
  • Tips

of people found this tip helpful

Tip: Jackknife Sit-Up

Exercise Rating
10/10

Jan 12, 2014 8:53 AM: It feels that work with the lower back. It can be difficult realize this exercise in the first days, but then your body will get accustom. I recommend you that work in your rest day stretching and flexibility routine. This will enhance your performance in this exercise and on another.



comment
Please login to rate this tip.

of people found this tip helpful

Tip: Jackknife Sit-Up

Exercise Rating
9/10

Oct 9, 2013 7:51 AM: This is an exercise worth doing. The combination of balance and strength actually work quite well for such a difficult exercise. Easy to perform, but still tough to do for a long time, it is a good alternative to a normal sit up.



comment
Please login to rate this tip.

of people found this review helpful

Review: Jackknife Sit-Up

Exercise Rating
10/10

Aug 8, 2013 11:18 PM: Excellent.



comment
Please login to rate this review.

of people found this review helpful

Review: Jackknife Sit-Up

Exercise Rating
10/10

Nov 18, 2012 4:51 PM: The pulse ups really get your abs burning



comment
Please login to rate this review.

of people found this review helpful

Review: Jackknife Sit-Up

Exercise Rating
10/10

Oct 7, 2012 11:27 PM: Do these with a medicine ball, amazing workout



comment
Please login to rate this review.

of people found this review helpful

Review: Jackknife Sit-Up

Exercise Rating
1/10

Jun 1, 2012 6:54 PM: Seriously, are people trying to destroy their low backs?



comment
Please login to rate this review.

of people found this review helpful

Review: Jackknife Sit-Up

Exercise Rating
N/A

Dec 14, 2011 8:40 PM: one of the most brutal ab exercises ever



comment
Please login to rate this review.

of people found this review helpful

Review: Jackknife Sit-Up

Exercise Rating
N/A

Dec 5, 2011 8:17 AM: This one burns like hell but I still love it



comment
Please login to rate this review.

of people found this review helpful

Review: Jackknife Sit-Up

Exercise Rating
10/10

Oct 28, 2011 5:35 PM: love it



comment
Please login to rate this review.

of people found this review helpful

Review: Jackknife Sit-Up

Exercise Rating
10/10

Aug 26, 2011 7:30 PM: great workout really tough on the abs. btw does work upper abs as well or its more towards just lower?



comment
Please login to rate this review.

Give Us Feedback:
Report A Problem
Site Feedback
Follow Us:
Twitter
Facebook
RSS Feeds
Bodybuilding.com Newsletter

Receive exciting features,
news & special offers from Bodybuilding.com