Plyometrics

Plyometrics are quick, powerful exercises that begin with a prestretch or countermovement and use the stretch-shortening cycle to increase muscular power.^{1Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 488.} Muscle and tendon store elastic energy during the stretch, while the stretch reflex also contributes to the movement that follows.^{1Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 488.} The push must follow immediately: a long pause or lowering phase lets that stored energy dissipate as heat.^{1Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 488.}

The NSCA distinguishes the exercise from the mechanism: plyometrics is what the client performs, while the stretch-shortening cycle describes what happens in the tissues.^{2National Strength and Conditioning Association, NSCA’s Basics of Strength and Conditioning Manual, p. 61.}

In practice

• Build an adequate strength base with conventional resistance training first.^{2National Strength and Conditioning Association, NSCA’s Basics of Strength and Conditioning Manual, p. 61.} Low-intensity hops and skips suit novices; drop jumps belong with advanced clients.^{2National Strength and Conditioning Association, NSCA’s Basics of Strength and Conditioning Manual, p. 61.}
• Count foot contacts to track training volume: suggested starting volumes are 80 to 100 per session for beginners, 100 to 120 for intermediate clients and 120 to 140 for advanced clients.^{3Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 493.}
• Allow full rest intervals: depth jumps may need 5 to 10 seconds between reps and 2 to 3 minutes between sets.^{3Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 493.} Avoid plyometric drills for the same body area on consecutive days.^{3Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 493.}
• Progress from lower- to higher-intensity drills, usually reducing volume as intensity rises.^{3Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 493.}