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Benefits of Isolation Exercise


What are the benefits to isolation exercise (iso squats, planks side planks)? On a recent training course by Michol Dalcourt, he brought up the question of how to prevent neck problems while doing ab exercises. It would be great to know any tips for prevention as many of my clients suffer from this. Thank you!


Isolation and isometric exercises have been very popular, given that most who engage in an exercise program do so under the context of working "muscles." This, of course, is very different than the way the body works. The body knows nothing of muscles, only movement (Bobath, 1980). If we operate under the assumption that we are working muscles, then we would naturally choose focused (or isolated) exercises. Side planks and iso squats would be the exercises that we would first choose!

However, and it is a big however, the body is designed far differently than this. Since we only know movement, then movement should be where we START. Remember, muscles are bio-pumps (they pump fluids around the body through their rhythmical contraction). Movement, therefore, is the key to a healthy body. Sustaining body positions does not teach the body to load and unload in three planes. To load means that you stretch the muscle (load), taking advantage of the proprioceptive and myotactic reflexes (stretch reflex) of the body. The unload is the product or result of the stretch - a contraction. This most efficient form of movement teaches the body to effectively disperse forces, increasing movement ability. Isometric exercises (which the body can do but prefers not to) increases localized forces and ischemia. Think about this: we load one area of the body too much and then rob that area of vital oxygen (ischemia). Does that sound effective? Much more strength is needed for these particular isometric exercises. It is no wonder that the body burns and starts to shift when doing isometric work. It is telling us to MOVE. So, if anything, these isometric/isolated exercises should be placed in a more advanced category. Moreover, isometric exercises (which require selective contraction) are far less biomechanically efficient compared to rhythmical exercises.

When doing isolated ab exercises, the neck muscles have to hold an isometric contraction. As such, more often than not they fatigue much more quickly than the abdominal complex (especially when a head forward posture is observed). If the neck is held statically too long, ischemia (lack of oxygen) results, and the body lets us know. It will burn and fatigue quickly. If the goal is to isolate the abs for aesthetic purposes, you could try a rope crunch.

So, do isolation exercises have any benefit?? Only if the individual needs isometric strength for a particular activity... AND THAT'S IT! Remember, these exercises should be PROGRESSED to as opposed to begun with.

I hope this sheds some light on our preferred way to move. Have fun!