Isometric exercises are contractions of a particular muscle or group of muscles. During isometric exercises, the muscle doesn't noticeably change length and the affected joint doesn't move. Isometric exercises don't effectively build strength but can help maintain muscle strength — often in a rehabilitative setting.
Because isometric exercises are done in one position without movement, they'll improve strength in only one particular position. You'd have to do various isometric exercises through your limb's whole range of motion to improve muscle strength across the range. In addition, since isometric exercises are done in a static position, they won't help improve speed or athletic performance. They can be useful, however, in enhancing stabilization — maintaining the position of the affected area — since muscles often contract isometrically to aid in stabilization.
Isometric exercises may be helpful to someone who has been injured or has a condition such as arthritis, which could make movement painful or be aggravated by using muscles to move a joint through the full range of motion. For instance, if you injure your rotator cuff, your doctor or physical therapist might initially recommend isometric exercises involving the group of muscles that helps stabilize the shoulder to maintain shoulder strength during recovery.
A recent study has shown that isometric exercises may also help lower your blood pressure. However, if you have high blood pressure, exercise at a lower level of intensity. Exercising at a higher level of intensity can cause a dramatic increase in your blood pressure during the activity. Check with your doctor before beginning isometric exercises if you have high blood pressure or any heart problems. Avoid holding your breath and straining during any weight training exercise, as this may cause a dangerous rise in blood pressure.
Nov. 25, 2014
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