Jack Knife abs are a great exercise that combines stimulation of the abdominal muscles with light aerobic effort.
Steps
Part 1 of 4: The Starting Position

Step 1. Lie on your back with your legs extended

Step 2. Stretch your arms behind your head
Part 2 of 4: Execution

Step 1. As you exhale, raise your arms and legs, keeping them straight
If you perform the movement correctly, you should balance on your lower back with your legs raised and stretched to form an angle of 35 ° -45 ° with the ground and your arms parallel to your legs.

Step 2. Breathing in, return to the starting position

Step 3. Repeat
Part 3 of 4: Increase the Difficulty

Step 1. Try using a medicine ball:
Lean with your stomach on the ball. Move your hands forward in small steps until the ball is under your ankles

Step 2. Bend your knees and bring the ball back towards your chest
You don't have to lower your hips or arch your back. Flex your abs to maintain balance.

Step 3. Return to the starting position by extending your legs
Part 4 of 4: Frequency

Step 1. 2 or 3 sets of 10-12 reps are a good start

Step 2. Be consistent
You should see results after 2-3 sets a day for four days a week for a couple of months. If you are impatient, increase your workload (do it carefully).
Advice
- This exercise is used to increase both strength and flexibility in the abdominals.
- If you want to lighten the exercise, keep your legs a little bent.
- Do not touch your feet with your hands, the limbs must be parallel.
- Training too much is harmful and does not bring results.