An isometric exerciser is any piece of fitness equipment that aids in performing strengthening exercises. Also called static exercise or contraction, an isometric exercise tightens a muscle or group of muscles without movement. This is performed by working against a stationary force where the muscles involved do not move joints through normal range of motion.
Exercises with an isometric exerciser have the ability to increase strength at specific, fixed joint positions. A joint is a connection point that attaches different bones together to allow for body movement. During a regular exercise routine, consisting of specific movements, an isotonic contraction of the muscles occurs. This is where the force or tension applied to the muscle remains the same through changes in muscle length.
When performing dynamic exercises, changes in the position of the body part results in two different types of contractions or muscle tightening. A concentric contraction is where the muscle shortens in response to an external force as is seen with bicep curls when the lower arm bends up towards the shoulder. When the muscle lengthens, an eccentric contraction occurs.
In isometric exercises the length of the muscle and the position of the joint remain unchanged but the amount of force applied to the muscles may change. This can increase the strength of the muscle in a specific position. The use of an isometric exerciser can aid in changing the force being put on the muscles without having to alter positioning.
Static or isometric exercise is beneficial in initial physical rehabilitation to build or maintain strength after an injury or surgical procedure where pain inhibits movement. Isometrics are also advantageous during physical activities requiring increased muscle power during certain positions. For example, push-ups can aid in boosting upper arm and chest strength. Increasing the number of repetitions results in enhancing endurance, not strength. Holding up the body in a push-up position with arms extended, an example of an isometric exercise, increases strength.
By adding an isometric exerciser, strength can be improved by alternating the amount of tension working against the tightened muscles. An isometric exerciser can also decrease the amount of adaptability of the muscles. In other words, while holding the push-up position can boost arm and chest strength, done over time, the body becomes accustom to the amount of force being applied to the arms and chest by the weight of the body. By confusing the muscles and adding a isometric chest exerciser, the arms and the chest muscles have to work harder, thus enhancing overall strength to these areas.
