The jack knives exercise works out the core muscles of your abdominals. It's an exercise that works great for your abdominal muscles. This is definetley an exercise that can and will tighten up those ab muscles.

This exercise will develop the entire core muscles of your abdominals if done correctly and properly.




Here are some tips to understand and implement as well as a description of how to do the exercise:

Tips:

• Contract your muscle during every repetition.
  
• Keep your kneck straight and do not pull your kneck forward.
  
• Contract your muscles until your elbows touches your knees.
• Complete your repetition without losing your balance or control.
  

• Begin this exercise by lying on a bench with your lower body not on the bench.
  
• Do complete crunch and bring our shoulders and our knees together.
  
• Contract all the way until your elbows touches your knees.
  
• Then repeat the process as needed.

Return to the top of the jack knives exercise page. Return to Abdominal Exercises