Isometric exercises, or isometrics, are a type of strength training where the angle of the joint and the length of the muscle do not change during the contraction. No visible movement is seen during these contractions. These types of exercises are thousands of years old and bodybuilders use them frequently in their training.
Isometric exercises are done by using the effort of the body against some form of resistance that will strengthen and tone the muscles, but the muscle length does not change. This resistance can be the body’s own weight, a structural item such as pressing against a wall or a door frame, free weights or weight machines.
Submaximal and Maximal Muscle Actions
Isometric exercises can be broken down into two different categories: submaximal muscle action and a maximal muscle action.
- A submaximal muscle action will involve the use of a movable object. This could be something such as using free weights and holding them out to the side. Submaximal muscle actions are used for rehabilitation.
- A maximal muscle action involves immovable objects. This can include a wall or a door frame that can be pushed against. Maximal muscle actions are used for strength and conditioning.
A full body isometric exercise that can be done is the Plank Bridge. To do this exercise, lay on your stomach with your elbows and forearms on the ground underneath your chest. Push yourself up so your body will form the shape of a bridge with your toes and forearms. Keep your back straight and your body tight. Hold this position for 30 seconds. Repeat 2 or 3 more times.
A Side Bridge is another isometric exercise that works the entire body. Lie on your side and bend your arm at your elbow. Press your body up on your arm and keep your body straight. Hold this position for 30 seconds. Repeat this exercise 2 to 3 times.
A standard push-up can be done as an isometric exercise. Starting from the traditional push-up position, lower yourself halfway down and hold in that position for 30 seconds. Complete the push-up by going down then back to the starting position. Repeat 2 to 3 times.
A squat can be done as an isometric exercise. Use a wall to guide and support you. Place your back against the wall and slide down as if you’re going to sit in a chair. When your legs are parallel to the ground, hold that position for 30 seconds. Repeat 2 to 3 times.
Guidelines for Isometric Exercises
Doing isometric exercises will cause your blood pressure to raise for the entire time you’re performing them, sometimes significantly. Blood pressure will return to a resting level, but the long duration of elevation can be harmful to anyone who has hypertension or any cardiovascular disease. Be sure you are breathing during the entire exercise. Holding your breath can cause your blood pressure to rise even more. Keep your abdominal muscles contracted. This will help keep your posture straight and to strengthen those muscles. Being aware of what your body is doing and what it should be doing will help you to get the most out of isometric exercises.