Also known as isometric exercise, isometrics are one form of strength training used by professional athletes as well as amateur fitness enthusiasts. The exercises are completed in a static position, making sure that the angle of the joints and the length or stretch of the muscles do not change during the period of contraction. This is accomplished by either working against some immovable object such as a wall, or by using resistance to challenge the muscles.
There are essentially two classes of isometrics. The first is known as overcoming isometric exercise. An example of this approach would be using the muscles of the arms to push against a stationary object. During the routine, the joints remain in the same position while the pushing activity generates work for the muscle groups involved.
A second form of isometrics is known as yielding isometric exercises. In a work out of this type, the key to success is making use of resistance training. This often involves some sort of activity that involves pulling while holding the joints and muscles in a static position. Like overcoming isometrics, the yielding approach causes the muscles to work and thus helps to build muscle tone and strength.
Isometrics are different from isotonic exercises in that the isotonic work-out does not require that the angle of the joints remain constant. Both approaches are considered helpful in developing muscle mass and building endurance. It is not unusual for exercise routines to include both isometrics and isotonics as part of the same session.
Unlike some forms of exercise, isometrics do not require a lot of equipment. In some cases, no equipment is required at all. One example of a simple isometric exercise involves using the body’s own musculature as the immovable object. By raising the arms to shoulder length and bending the elbows to allow the palms of the hands to come together, it is possible to use the muscles of each arm to work against the other.
There are other simple isometrics that can be done in the home with ease. Pushing against a door frame is one example. It is also possible to make use of free weights in isometric workouts by holding the weight in a fixed position for a certain amount of time.