Chapter 18 of the Essentials of Strength Training and Conditioning covers all of the major steps involved in designing a plyometric training program. These steps are largely the same as those in resistance and aerobic training.

Program Design and Technique for Plyometric Training

• Plyometric exercises are those that enable a muscle to reach maximal force in the shortest time possible. They are used to increase power. Plyometric exercise is a quick, powerful movement using a pre-stretch, or countermovement, that involves the stretch shortening cycle.

Plyometric Mechanics and Physiology

• Power - the time rate of doing work or a measure of the ability to exert force at a higher speed.
• Series Elastic Component (SEC) - the relationship between tendon and bone. When tendons are stretched from bone by muscle, stored muscle energy is created. If the muscle contracts immediately then that energy is released and force production is increased. If not the energy dissipates as heat.
• Eccentric Phase - negative work performed on a muscle.
• Potentiation - a change in the strength of a nerve impulse caused by stretch. This can be short term like in the SSC or long term like in phase potentiation in the design of a program (the early phases of a program affecting the phases that follow).
• Stretch Reflex - an involuntary muscular contraction to an external stimulus that stretches muscle.
• Muscle Spindles - proprioceptive organs that run parallel to other muscle fibers and detect changes in muscle length.
• Stretch-Shortening Cycle (SSC) - a three phased muscle action that is manipulated in this chapter to create powerful movements. Phase I is eccentric and involves loading the SEC with stored energy via a stretch and muscle spindle activation. Phase II is a transitional pause phase called amortization. Phase III is a concentric muscle action that takes advantage of all of the stored energy.
• Concentric Phases - the time during the SSC that the agonist muscle is performing action.
• Amortization Phase - a transitional pause between the eccentric and concentric phases of the SSC. The shorter this phase is, the more powerful the contraction will be as the most energy will be released from the stored phase.

Program Design

• Throw - an upper body plyometric exercise.
• Plyometric training can benefit running and cycling performance for endurance athletes by allowing muscles to produce more force with less energy.
• Jumps in Place - vertical jumping and landing in the same spot without resting. The time between jumps is the SSC amortization phase.
• Standing Jumps - vertical or horizontal components. One maximal jump with rest between.
• Multiple Hops and Jumps - repeated jumps, may be in place or moving.
• Bounds-exaggerated movements that cover greater distances than other jumps.
• Box Drills - jumping onto, or off of boxes.
• Depth Jumps - gravity and the athlete's weight are used to increase the intensity of the jump. The athlete steps or jumps off of a box immediately into a jump. May involve one or both legs.
• Push-Ups - an upper body exercise. Some variations can be used plyometrically.
• It is difficult to provide frequency or recovery between session recommendations for plyometrics but, there are general suggested volumes of 80-90 foot contacts for beginners, 100-120 for intermediates with some experience and 120-140 for advanced athletes with considerable experience.
• Plyometric program design includes mode, intensity, frequency, recovery, volume, program length, progression and recovery.

Age Considerations

• Masters and young athletes can add plyometrics to their training with the right thought and consideration. High intensity is contraindicated for the youth as their growth plates likely have not closed.

Plyometrics and Other Forms of Exercise

• Since plyometrics are only a part of the athlete's training program, thought must be placed into how the other training will take priority.
• Complex Training - high intensity resistance training followed by plyometrics.
• A combined program can involve low intensity lower body plyometrics being performed on heavy upper body resistance training days and vice versa, complex training and combining resistance training exercises with plyometric exercises to further enhance gains in muscular power.
• Plyometrics should be performed before aerobic exercise as this may have a negative effect on power production.

Safety Considerations

• Plyometrics are not inherently riskier than other forms of exercise. Typically injury only occurs when there is a lack of a strength and conditioning base, an inadequate warm-up, an improper arrangement of lead up exercises, poor conditions, improper volume or intensity or a lack of skill.
• Technique is a major factor in the pretraining safety evaluation. Strength in the athlete's 1RM Back Squat should be at least 1.5 times her body weight.
• Balance - the ability to maintain a position without moving for a period of time.
• Athletes who weigh more than 220 pounds are exposed to greater compressive force that predispose them to injury. Depth jumps from heights greater than 18 inches should be avoided.