The ABC’s of Pliometric Physiology

Track and field, basketball, football, baseball, gymnastics, volleyball, and even golf are some of the sports that can benefit from pliometrics. Athletes who participate in sports, which require strength, speed and explosive power, should incorporate pliometrics into a year-round program.

There are a number of reasons why athletes decide to train with Pliometrics.

These are all valid reasons to begin to train using pliometrics.

In order to begin to implement the workouts, you must first begin to understand how the body works. First of all, pliometrics does not train muscles! Pliometrics trains the nervous system. Muscles derive their information from the central nervous system (brain). This information travels through the spinal cord out into the peripheral nervous system, which extends out from the spinal cord between the vertebrae and ultimately to every muscle in the body.

The information received and processed by the central nervous system pertains to muscle length (at any given point), rate, and force of contraction necessary to execute the movement pattern that is being attempted. Many other messages are sent and received in milliseconds or even faster depending on the coding pattern and firing sequence of the neuron-transmitters involved.

What is sending this information to the brain? Sensors (proprioceptors) play the role of presetting muscle tension and relaying sensory input related to rapid muscle stretching for activation of the “stretch-reflex”. The stretch, or myotactic reflex, responds to the rate at which a muscle is stretched and is among the fastest in the human body. The reason for this is the direct connection from sensory receptors in the muscle to cells in the spinal cord and back to the muscle fibers responsible for contraction. Any other type of reflex is slower than the stretch reflex because signals must be transmitted through several different channels and to the central nervous system before a reaction is elicited.

What is the significance of a faster contraction? Muscle undergoes a contraction faster during a stretch shortening cycle than during any other method of contraction. A thought-out response to muscle stretch would be too slow and thus make the athlete too late for the action necessary to perform.

Response time and response strength are both considerations when determining how plyometrics relates and applies to sport performance. In some cases the response time may remain the same even after normal strength training, because traditional forms of training does not change the speed of the response in terms of muscle contraction.

The bottom line is that pliometric training creates a more rapid muscular concentric contraction, which will lead to a greater concentric force production and shorter response time. The result is a more forceful movement for overcoming the inertia of an object, whether it is the individual’s own body weight or the weight of an object.