Warm-up

A warm-up is activity that raises body and muscle temperature to prepare a client for vigorous exercise.^{1Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 292.} Most benefits depend on the temperature rise, including increased muscle blood flow, faster nerve impulses, lower muscle viscosity and greater range of motion.^{1Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 292.} Its effect on injury risk is unclear, though the evidence suggests possible benefits.^{2Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 334.}

A warm-up usually has a general phase of light aerobic activity, such as a few minutes of jogging, skipping or cycling.^{2Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 334.} The specific phase rehearses the session’s movements, such as lighter bench press sets before the work weight, warming the same muscles while practicing the lift.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 294.}

In practice

• Allow about 5 to 15 minutes, or until the client breaks a light sweat; fitter clients may need a longer or harder warm-up.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 294.}
• Avoid fatigue and finish no more than 15 minutes before the main work, since benefits start to fade after that.^{2Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 334.}
• Static stretching alone barely raises core temperature, so stretch after the client starts to perspire rather than substituting it for a warm-up.^{4Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 293.}
• For lifting, Rippetoe and colleagues start each exercise with an empty bar, then add weight in even jumps over 3 to 5 sets.^{5Rippetoe et al., Practical Programming for Strength Training, 3rd ed., p. 136.} A final warm-up set too close to the work weight tires the client instead of preparing them.^{5Rippetoe et al., Practical Programming for Strength Training, 3rd ed., p. 136.}