Isometric Exercises - Some Common Questions Answered

Isometric Exercises are a form of training in which the muscles attempt to contract and move but are prevented from doing so. So, curling a dumbell is not an isometric movement. However, trying to push against an immovable object like a house is an isometric contraction.

Often, this form of exercise is called self-resistance as one limb is often pitted against another. Isometrics have been around for thousands of years and are a major part of disciplines like Yoga and the Martial Arts. They were a major part of the physical culture movement in both North America and Europe, but have died off somewhat during the second half of the last century. It is not my intention in this article to go into why this happened. Rather, I want to answer some common questions you might have about isometric exercises:

What is the concept of the isometric contraction and why is it so effective?

The whole point of performing an isometric contraction is to get to the last rep first!  Let me explain. Let's say you are performing some barbell curls. The whole point of weight lifting is to continue the movement until you cannot lift it anymore. You are trying to train to the point of failure by exhausting all of the muscle fibers in your arm. When your perform an isometric exercise, you are attempting to do the same thing. Here's how it works.

Every muscle in your body is made up off different fibers that have varying levels of strength, explosiveness, and stamina. When you perform a fast motion like throwing a ball, you are utilizing the fast twitch muscles in your arm. When you push against a heavy object, you are utilizing the slower twitch fibers. When you perform an isometric contraction, you are forcing ALL of the fibers to become engaged.

Mother nature is very efficient. She always uses the exact minimum number of muscle fibers she has to for any movement. If she can get away with using two muscles to throw a ball, that's all she uses. However, with isometrics, you are constantly straining, but NEVER moving. This forces your body to use every muscle fiber RIGHT away. This is the secret of isometric contractions, and why they allow you to "get to the last rep, first".

Can I get a complete workout using isometric exercises alone?

There are many components to fitness and being healthy. They are strength, flexibility, endurance (both muscular and cardio wise) balance, coordination, reaction time and aesthetics. Isometrics are very good at building strength and aesthetics. It can also prepare you for other physical activities that will improve the other components I just mentioned. However, it will not dramatically improve them by itself.

Still, as a form of exercise that can be done quickly and will also improve your look and strength, they really can't be beat.

How long do I need to hold an isometric contraction to get the full effect?

This really depends on your and what you want to achieve. The more intense the contraction, the shorter it should be held for. An isometric contraction of 80% of your maximum should not be held longer than 12 seconds. This is used for building maximum strength. However, if you want to build muscle size, you will want to hold the contraction at 35% of your max for 2 to 3 minutes. Of course, if you want to build size, you need to watch your diet as well.

Do isometric exercises pose the same risk of injury as other forms of strength training?

When performed correctly with proper breathing procedures, isometric training is probably the safest form of strength training that there is. There is no worries about lifting weights in an awkward fashion or straining yourself. The key is to slowly build up the tension while breathing in for 4 seconds, holding the contraction for 7 seconds while your breathe out, then letting the tension dissipate while your breathe in again for 4 seconds. Remember, isometrics were used to rehabilitate injured soldiers after WWII.

David Nordmark is a Vancouver based fitness consultant as well as the owner and operator of animal-kingdom-workouts.com/index.html Animal-Kingdom-Workouts.com, a fitness site with a unique twist. For more information on body weight workouts, isometric exercises and other fitness issues, also check out his bodyweight-exercises.animal-kingdom-workouts.com bodyweight exercises blog.