What Are Plyometrics?

By Bruce Cohn
Concord Journal, June, 2001
 
Most sports conditioning programs employ plyometric or jump training as a method to improve an athlete’s speed and explosive power. These series of exercises were developed and first used in the 1970s for Eastern European athletes. The term plyometrics literally means “measurable increases” and were widely credited as a key to these athletes’ growing dominance in Olympic track and field events. Their popularity has spread beyond track and field to applications in power development for many sports.

Plyometrics consist of jumping and throwing movements that are designed to enable a muscle to reach maximum strength in as short a time as possible. This is referred to as power. Plyometric exercises exploit a muscle’s inherent elastic quality known as the stretch-shortening cycle. The rapid lengthening of a muscle enables it to briefly store potential energy for a more powerful contraction. (We have all experienced this in the doctor’s office with the testing of the knee-jerk reflex.) By training the nervous system to react quickly to the lengthening of a muscle with a rapid shortening, the maximum force produced by the muscle can be increased.

There are many benefits to plyometric training when it is performed under proper supervision. These exercises develop explosiveness and speed and tend to be more sport-specific than traditional strength training. They generally do not require expensive equipment and are progressive in nature, with a range of low to high intensity for each exercise. There have also been studies supporting the role of jump training programs in decreasing the incidence of serious knee injuries in female athletes. Because of the need for correct technique, appropriate landing surface and requisite strength/flexibility base; plyometrics should be taught under the supervision of a trained and certified coach.

Bruce Cohn is the Strength and Conditioning Coach at the Middlesex School in Concord. He runs FIT-TO-GO Total Sports Conditioning and is a nationally certified Strength and Conditioning Specialist. Bruce can be reached at 781-316-0061 or brucegym@rcn.com.