How to do the Swiss Ball Jackknife
Workout Guides Women

How to do the Swiss Ball Jackknife & Get a Flat Stomach & Toned Abs

Estimated Reading Time: 4 minutes

If you have been doing abs work for a while now you will, undoubtedly, be looking for some new exercises to keep your abdominal workouts spicy. Today I am going to show you how to do a Swiss Ball Jackknife – a very powerful exercises for working your lower and upper abs as well as your back and arms.

Preparing for the Swiss Ball Jackknife

Before you do any abdominal exercise you need to make sure you have covered a few areas. These include:

  • Ensuring you use the proper technique
    Make sure you always study the exercise well and learn how to do it with the perfect technique. If you perform any exercise incorrectly you run the risk of developing a long term injury that will haunt you for years.
  • Ensuring you warm up
    Make sure you do a warm up before you do any resistance exercise. Again, this helps to prevent injuries.
  • Ensuring you target the right muscles
    You would be surprised to know how many women do exercises that they think targets one muscle but, in fact, it targets something completely different. Before you do this exercise you need to know where your abdominal muscles are located and how they work.

Once you have these three things under control you will be ready to start the exercise. I cannot emphasize enough how important it is to perform every exercise with the perfect technique. It will prevent injuries and help you get that sexy body a lot quicker.

How to do the Swiss Ball Jackknife for Toned Abs

Now we can move on to the exciting part! This exercise is an amazing way to target your upper and lower abs in one exercise. It also hits your arms and shoulders, your back and even your butt and legs. Many women find this is a great exercise to toned the whole body as it requires strength from a lot of different areas to complete properly.

Engage your pelvic floor muscles
It is very important when performing abdominal exercises that you engage your core muscles correctly. If you don’t you run the risk of completely missing out on the work that your lower abs should be doing. They simply won’t engage. To turn on your core you need to engage your pelvic floor muscles (the ones that you tense when you are busting for the toilet). You also need to tense your major abs muscles by pulling your belly button in as far as you can. Hold this throughout the exercise.

STEP ONE – Position Yourself on the Swiss Ball

The first part of the jackknife is done by positioning your body on the Swiss ball in the correct posture. Without the correct posture your whole exercise will feel unbalanced and weak. To do this you need to:

  • Place your feet on the ball so they are balanced and stable. Close together is best but you can have a little space if you need it.
  • Place your hands shoulder width a part and lock your elbows so you can support your body weight.
  • Make sure that your shoulders are back by lengthening the distance between your ear and your shoulders
  • Make sure your back is perfectly straight; not curved upwards or downwards. This is vital.
  • Tense your abs and pelvic floor muscles.

Make sure you feel comfortable and secure. It will take some practice to get the balance correct but if you keep your posture as illustrated above you will find the stability comes quite naturally.

STEP TWO – The Actual Jackknife “Crunch” Movement

From the initial starting position you will now do the main jackknife or “crunch” part of the movement which is where the majority of the work is done. In order to do this correctly you need to:

  • Very slowly bring your knees toward your chest by crunching your abs and rolling the fitness ball forward
  • At the top of the motion you tense your abs again as you breathe out
  • Very slowly return your legs to the original position making sure your abs stay tensed and firm

Repeat the above sets until your abs are too tired to continue. This is called “failure”. You should fail after about 15 to 20 repetitions if your technique is correct. Make sure you do not continue if your execution starts to get sloppy as you will not be targeting the correct muscles and you might do yourself an injury.


The Swiss Ball jackknife is an amazing exercise for toning your abs and getting a flat stomach. It is quite advanced so build up slowly by performing a regular pilates abs crunch. When you feel like you are ready get your fitness ball and go for it! You will see results in just a few sessions.

How to do the Swiss Ball Jackknife & Get a Flat Stomach & Toned Abs
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