Originally developed in East Bloc countries, plyometric exercises are used to translate the increased strength from resistance training into increased speed and power. Although plyometrics are designed for intermediate and advanced athletes, they may be able to help you improve your game.
Beginners in fitness need to go slowly to learn proper exercise technique. Improper exercise technique increases the risk of injury. Since the fitness level of each participant is unknown and there is less supervision, there is an increased risk of injury, especially if the participant has pre-existing injuries. Therefore, the risk of use in general fitness classes are too great when related to the benefits. Coaches in athletic events can gauge whether the athlete is ready for plyometrics and closely watch their technique to avoid injury.
In athletics, as well as general fitness training, there are five stages of development. The first stage is neuromuscular facilitation, also called kinesthetic awareness. This stage involves learning to control how the body moves. The second stage is developing muscular endurance, which allows a person to be able to complete the workout routine without undue fatigue. The third and fourth stages (increased muscle mass and increased strength [the ability to exert increased force]) occur at about the same time. The fifth and final stage is development of power, which is strength with speed. The fifth stage is where plyometrics is used most effectively and requires prior development of the other four athletic qualities.
Initially, resistance training, stretching, sprints and sports drills should be sufficient to improve speed and power. The rule of thumb the Soviets used for commencing lower body plyometrics was the athlete should be capable of squatting 150 percent of bodyweight. Until that time, speed can be improved significantly with strength training and sports training techniques. The athlete’s joints and muscles need to be sturdy enough to withstand the high forces generated by plyometrics. The connective tissue doesn’t increase in strength as fast as the muscles because they have less blood supply. The initial strength change produced by resistance training is via neurological adaptation; i.e., increased motor unit recruitment and muscle fiber contraction synchronicity. Soon, there is an increase in contractile proteins in the muscle fibers, also known as muscle growth. Over time the tendons, ligaments and joint capsule increase in thickness and structural integrity. Once the athlete has become strong enough, plyometric training can begin.
Plyometric training is most applicable to sports requiring speed or power as a primary requisite for victory. The sports most clearly in this category include track and field events such as high jump, long jump, pole vault, high hurdles, shot-put, discus, javelin and the hammer-throw. Other sports in this category include boxing, martial arts, ice hockey, sprint distances in running and swimming, Olympic weightlifting and football. Sports where power and speed play a less decisive role are those where strategy, endurance or raw strength are more important. These sports include, among others, basketball, baseball, badminton, wrestling, table tennis, tennis, arm wrestling, gymnastics, ski jump, downhill skiing, water skiing and surfing.
In running, jumping and many other athletic events, the athletes’ foot or hand is in contact with the ground, ball or opponent only for a fraction of a second before the next contraction occurs. The pre-stretch that occurs when running or jumping helps the next contraction be more rapid and forceful. The body has a neurological inhibition that prevents the muscles from contracting so powerfully that it damages the tendon, or the attached bone. This inhibitory mechanism is actually set too conservatively. Utilizing training methods that use the pre-stretch contraction partly reduces this inhibition, allowing a more rapid and powerful contraction than before.
To be continued…