Isokinetic Muscle Testing

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It is not necessary for every weight trainee to perform maximum muscle testing. If you weight train to improve your body image or for general fitness, there is no reason for you to partake in muscle testing. However, if you want an objective method of determining muscle strength for a specific muscle group, you would benefit from performing isokinetic testing.


Isokinetic strength testing is one method of maximum testing. The term "isokinetic" refers to constant speed. Isokinetic testing requires a special machine that controls your speed of movement while you perform the exercise. As your torque changes while producing the movement, the machine will adjust its resistance to keep the speed of movement the same. The machines are synchronized with a computer that can graph the speed and torque produced throughout the movement.

Types of Movements

The premise is to test the strength of a single muscle group as it is acting around one joint. Isokinetic testing is most often performed to test knee flexion and extension strength. Many isokinetic machines do have attachments that enable other movements to be tested, such as elbow flexion and extension strength or hip abduction and adduction strength.


Testing for maximum strength in any lift can be dangerous without ensuring that you are trained enough to complete a maximum test. Maximum tests put a lot of stress on you, and if you are not trained highly enough to handle the stress and strain placed on your muscles and other tissues, you could become injured. You should be comfortable performing exercises on the machine before providing a maximum effort on it because isokinetic movements are restricted by the machine. According to a study by Brian Wallace published in 2010 in the "International Journal of Fitness," your results can be affected based on how familiar you are using the machine.


Make sure the isokinetic machine is sturdy and adjusted properly for you. With isokinetic testing, the position of the person in relation to the machine is also important to ensure the test's accuracy and the person's safety. You should only perform isokinetic tests with a person that is experienced in setting up the machine. No distractions that could cause you to lose your focus during the testing should be present.

Practical Uses

Isokinetic machines are mostly used in rehabilitation or research settings. They are used in rehabilitation because they can allow for maximum effort throughout the range of motion, according to Isokinetic testing is used in research because the nature of the testing is seen as reliable and consistent. For research purposes, five to 10 repetitions are typically performed, and the maximum torque produced in any of those repetitions is recorded. It is not practical to use isokinetic machines for day-to-day training because the movements are single-joint, when in real life most movements involve multiple joints. Additionally, isokinetic machines cost tens of thousands of dollars and take up a lot of space.