A Definition of Isometric Exercise

Article by David Nordmark

There is a lot of confusion out there as to just what constitutes an isometric exercise. Many people believe that Charles Atlas built his great physique using isometric exercise. This is not the case. Charles Atlas taught a series of moving self-resistance exercises that he called “dynamic tension” combined with bodyweight exercises like pushups. The key thing about an isometric exercise is that it involves no movement at all. Let’s say that you press your two palms together as hard as you can. Obviously you can really work your muscles (especially your chest muscles) with this kind of exercise. However when you do this there is no movement at all. This is called an isometric contraction. When done correctly neither the joint angle or muscle length changes.

Why does this form of exercise work? Essentially what isometric exercises allow you to do is to trick the body into using as many of the muscle fibers as possible all at once. This is called the “Synapse Effect” and this is how it works.

Every muscle in your body is made up of hundreds of individual muscle fibers of varying length and abilities. When you go to perform any action your mind activates the bare number of muscle fibers required to accomplish the task. So if you pick up a coffee cup your mind will only activate those muscle fibers that are absolutely needed. If you pick up a heavy weight it will activate that much more, but always the bare minimum.

Now lets say you engage in an isometric exercise which utilizes and isometric contraction. The example above of pressing your palms together is a good one. When you do so your mind is trying to move both of your arms at the same time. It has no idea that they are opposed to one another so it assumes that the object you are trying to move is very heavy. Therefore it continually recruits more and more muscle fibers in a vain attempt to move your arms. This is why it’s possible to exhaust ALL of your muscle fibers with isometrics within 12 seconds, whereas it takes 3 sets of 12 (for example) using conventional weight lifting.

Isometrics Exercises have several advantages over more conventional exercise methods. Among these are:

They are extremely safe – There’s no fear of lifting too much weight or twisting a limb in an awkward direction.Isometrics will save you a lot of time – There’s no need to go to a gym and it’s remember there’s only one movement vs 3 sets of 12.They are amazing for building strength – Many old time strongmen, such as Alexander Zass, only used isometrics. They never touched weights.They are great at sculpting the body – They make it possible to achieve a fitness / bodybuilder look without spending hours upon hours in a gym.Isometric exercises can be done anywhere – At home, in the office, in hotels when traveling. There’s no excuse not to get your workout in!

At any rate there you have it. To sum up isometric exercise is a form of physical activity in which the muscle length and joint angle do not change. Although they have fallen out of favor somewhat in recent years they remain an incredibly effective exercise system. You may want to give them a try yourself!