Muscular power

Muscular power is force multiplied by velocity.^{1Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 45.} Powerlifting involves high forces at low speeds and produces less mechanical power than Olympic weightlifting, despite its name.^{1Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 45.} Time limits the force a client can apply: a countermovement jump’s concentric phase may last only about 235 milliseconds, and no more force can be applied once the feet leave the ground.^{2Hoffman, NSCA’s Guide to Program Design, p. 116.}

Power declines faster than any other element of muscle fitness as people age.^{3Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 443.} It’s also a main predictor of muscle function and independence in old age.^{4Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 353.}

In practice

• Build strength first in weaker clients.^{5Hoffman, NSCA’s Guide to Program Design, p. 119.},^{6Hoffman, NSCA’s Guide to Program Design, p. 133.} Heavy training raises maximal power in untrained and moderately trained people, but the gains are much smaller in strong, experienced clients.^{5Hoffman, NSCA’s Guide to Program Design, p. 119.},^{6Hoffman, NSCA’s Guide to Program Design, p. 133.}
• Power gains are load-specific, improving most at and around the load used in training.^{7Hoffman, NSCA’s Guide to Program Design, p. 132.}
• For lifts such as the clean and snatch, the NSCA assigns 80 to 90% of one-repetition maximum (1RM) for 1 or 2 reps in single-effort events, or 75 to 85% for 3 to 5 reps in repeated efforts.^{8Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 474.} Those loads are lighter than the rep counts imply, so every rep can be fast.^{8Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 474.}
• ACSM recommends power training such as medicine ball throws for older clients; sets of 4 reps or fewer maintain power output better.^{3Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 443.}