When you think “exercise”, you probably imagine some sort of movement. And, in most cases, you’d be spot on. Isometric exercises however are a special case, where you exercise without actually moving.

Do not for a second imagine that this makes them any easier to perform.

Exercises involving movement tend to offer different resistances during the movement. If you take a dumbbell curl, for instance, the greatest resistance is created about half-way through, when the dumbbell is furthest from your body and the leverage is greatest. In this kind of exercise, you only stay at the point of maximum resistance for a fraction of a second.

The idea behind isometrics is that you place your body under a constant stress, or exert a force against an immovable object (pushing or pulling), maintaining it for a few seconds at a time. The duration varies from exercise to exercise.

Building strength

In general, isometrics do not promote muscle growth, as the eccentric-concentric movement is missing, but they help increase strength. Bear in mind though that this increase is usually limited to the position exercised.

For example, if you do isometric arm exercises with your arms at 45 degrees, then you will get better at dealing with situations where your arms are at 45 degrees, but there will be no significant improvement at 30 or 60 degrees.

However, isometrics can be used to get you out of sticking points in other exercises – if you notice that you have a problem with a particular position in an exercise, it is easy to make an isometric exercise to strengthen that position.

You can easily repeat the exercises at different positions to round them out.

Make it last

Since these exercises do not involve movement, they are more usually measured by time.

In exercises where you actively exert force, like pushing at a wall or a door frame, you should be exerting maximum force. Most of these exercises only last for a few seconds – 10 seconds are enough in most cases. If you want to go for endurance, you can dial down to about half the effort, and do 30 seconds to a minute.

In exercises where you are holding a position, like a plank, you can go as long as you like.

Once you get beyond a couple of minutes, it really becomes a question of willpower – your body can only improve so much through one session. However, you don’t need to worry about overdoing it. Without eccentric and concentric movement, you are less likely to experience delayed-onset muscle soreness from them.

Some examples

Our favourite isometric exercise is the abdominal plank. This is an excellent exercise to strengthen the abdominals. Done to failure, 30 seconds to one minute is good going.

Another good isometric exercise for the legs is the Chinese chair – just “sit” on the air with your back to a wall. It burns!

In reality, anything can be made into an isometric exercise. Pause halfway down a push up or halfway up a pull up and stay there. Lift a barbell until your elbows are at 90 degrees and stay there. All of these are examples of isometric exercises!

Isometrics are easy to learn, can be extremely useful and require very little or no equipment. They’re an excellent addition to any training toolkit.

Header image: “Who said you couldn’t move mountains?” by Christine Majul (CC BY 2.0)