Plyometrics - Core Strength

Plyometrics - Core Strength

Author: Lyneene Orsini


Core Muscles

Inner Core

  • Transverse Abdominis(TA)
  • Multifidus

Outer Core

  • Rectus Abdominis
  • Internal and External Obliques


A Healthy Back

·       Brain activates inner core muscles when low loads are placed on the spine. The brain is programmed to contract deep muscles to provide stiffness between individual segments of the spine to protect spine from stress or strain.

·       TA & Multifidus work at all times during body movement, and co-contract to help create a stable spine.

·       Muscles are small and deep they have low activation threshold.

·       Brain contracts outer core muscles later, when moderate to high loads are placed on the spine, thus controlling the whole spine in their region.

·       As more spine stability is required, specific muscles of the outer unit are activated for dynamic control; muscle activation is dependent on the direction of forces applied and the intensity or weight of the load.

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This exercise is like a floor crunch or sit up. The idea here is to flex at the spine rather than the hips, as you will see most commonly in the traditional sit up method.

Us you sit up, focus on pushing your hips up toward the sky, and your lower back in to the ball.  This will help eliminate hip flexion, and enhance spinal flexion.

  • Points to consider:
    • There is no need to sit all the way up, unless you need a rest at the top!


Oblique Crunch


This exercise is a variation to the crunch.  The twisting motion activates your oblique side muscles.

As you perform half a sit up on the ball, simultaneously twist your upper body to once side, return to starting position.  When you crunch up the second time, twist to the opposite side.  Keep alternating.



Including the jacknife in your balance ball fitness abs workout will also help to enhance some upper body strength.

Start in push up as illustrated in position 1.  Bring your knees to your chest and slowly return to the starting position.

Try not to let your hips 'dip' throughout the movement.  Keep your hips rigid and at or above the level of your body to ensure activation of the abdominal muscles.

Side Crunch


This exercise is best done with your feet against the wall to keep you from falling over! 

Place the top leg in front with your hands across your chest.  As you lift your upper body to position 2, try to visualize pushing your hips up in the same direction.  This will help get more ‘squeeze’ out of your side muscles.

  • Points to consider:

The further you hold your arms out, the harder the exercise.  You can progress to holding your hands on your temple, then having your arms out above/in front of your head.

Class Activity 1


Any fitness expert will tell you that for a good strong core (midsection), it is essential to include lower back exercises.  You can include any of the following exercises in your balance ball fitness abs workout routine.


Name the major muscles in the upper and lower back


Alternate Arm Raises

Alternate Arm Leg Raise


Slowly raise one arm and the opposite leg simultaneously.  Touch both to the floor, and alternate.  Raise arm/leg in line with your body and hold the position for a second at the top of the movement.

Hip Raises Video

Hip Extensions


Keep your hands by your side for balance, raise you hips of the floor to position number 2.  Pause for a second and return.

Straight leg Bridge



Keeping your hands by your side for balance, raise your hips off the floor so your upper body and thighs are in line. Return slowly to start position.

  • Points to consider:
    • Can also be used as part of your lower body/leg workout as bridges utilise quite a lot of the hamstrings
  • Variations:

Can be done with single leg to increase difficulty


Back Extensions


Start with arms across chest in position 1. Lift your upper body so your whole body comes in to line. No need to hyperextend.  Return to starting position.

  • Variations:
    • As a progression and to increase difficulty, you can put your hands on your head. The further out your hands are from the ball, the harder this exercise.  Therefore, holding your arms straight out will increase difficulty again. 

Advanced alternate arm leg raises

Alternate Arm/Leg Raises Advanced


Find balance point on ball as pictured in position one.  Slowly raise one arm and the opposing leg simultaneously until they are in line with your upper body.  Return to starting position, and alternate arm/leg.

  • Points to consider:
    • It may be worthwhile to practice this balance ball fitness abs workout exercise on a soft floor! 

Leg Curls


This one not only works your hamstrings, but it also strengthens your lower back and butt muscles, whilst at the same time working on your balance.  Using one leg at a time really increases the difficulty level, and so is a progression from the above exercise.

Begin with hips off the floor as shown in position 1.  Keep your hips still as you curl the ball in towards you.  It is important with this exercise that you return back to the starting position slowly to emphasize the use of you hamstring muscles (back of legs).

  • Variations:
    • As a progression from the standard leg curl (above) to the one legged curl you can progress to this exercise by curling the ball towards you with both legs, and returning back to the starting position with one leg (obviously alternating).

Laboratory Task 1


In groups of 4 work through the following questions in preparation for class discussion.

Question 1: What are the pros and cons of core exercises using only floor work?

Question 2: What are the pros and cons of using the fitball?

Question 3: How would you transfer the same exercise to the floor or ball?

Question 4: What is is the correct chin to chest angle?

Question 5: What are some safety issues when working with a fitball?

Question 6: What is bracing?