Isometric muscle training has been around for thousands of years and is still seen today in yoga and pilates workouts. In resistance training, isometrics are still used as a method of improving strength and muscle size as well as a means of testing your strength.
Definition
The National Strength and Conditioning Association, or NSCA, defines isometrics as a muscle action in which the length of the muscle doesn't change. This is because the force generated within the muscle is equal to the resistive force. For example, when you push against a wall, your body is exerting a great amount of energy trying to move the wall but it doesn't budge. You can feel your muscles working even though the length does not change.
Testing Methods
Manual tests of isometric strength are popular in the area of injury rehabilitation. These are manual tests performed on you by a trained therapist. Basically, you push or pull with the injured body part against your therapist, who gauges your progress. It's good for comparison but is subjective. There are also devices such as a hand dynamometer, which can measure grip strength. Holding the device, you squeeze it as hard as you can and the dynamometer registers the force in pounds that you exert.
Significance
Testing isometric muscle contraction is useful in that specific activity. There isn't a strong correlation between isometric muscle strength and your performance in sports activities. They also are joint angle specific. For example, the force you can exert on a hand dynamometer is different depending on how open or closed your hand is. In a tight-fisted position, you're able to exert more force than if your hand were open wider.
Benefits
Isometric muscle testing is most beneficial as a way to determine recovery after an injury. As you go through your rehab program, your therapist can re-test you and record your progress. This determines whether your current program is improving the strength of your injured muscle or limb, or if changes must be made. As a method of resistance training, isometrics is beneficial in increasing muscle strength and size.
Warning
In a rehab setting, isometrics are not usually too intense because you're dealing with injured people. However, people who have high blood pressure should not perform isometric tests on an object where they can exert maximal force, or as a way of improving strength. Isometrics can increase blood pressure and heart rate because it restricts blood flow due to muscle contraction. And if you hold your breath, this increases your heart rate and blood pressure.
Member Comments