Maximum heart rate

Maximum heart rate is the highest heart rate a client reaches as exercise workload increases.^{1Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 442.} The NSCA text says finding the true maximum requires a graded exercise test that continues until heart rate no longer rises with workload.^{1Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 442.} Trainers usually estimate max heart rate as 220 minus age, but that can be off by 10 to 15 beats per minute either way: a 20-year-old predicted at 200 could be anywhere from 185 to 215.^{1Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 442.}

Other equations include 208 minus 0.7 times age for healthy adults, and 206 minus 0.88 times age, developed in middle-aged women.^{2Ozemek et al., ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed., p. 347.} Maximum heart rate doesn’t usually change with aerobic training.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 38.} Individuals can sit far from any formula: Daniels tested one runner whose maximum was 148 at age 30 and 146 at 55, and another who reached 192 at age 50.^{4Daniels, Daniels’ Running Formula, 4th ed., p. 76.}

In practice

• The NSCA text considers the age formula close enough for submaximal program design because clients shouldn’t reach their maximum in normal aerobic training.^{1Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 442.}
• For clients on medications such as beta blockers that blunt the heart-rate response, set intensity with a method that isn’t based on heart rate.^{1Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 442.}
• Use a maximum measured in a graded test instead of an estimate.^{5Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 445.}
• For runners, Daniels finds the maximum with repeated hard 2-minute uphill runs, stopping once heart rate no longer climbs from one run to the next.^{4Daniels, Daniels’ Running Formula, 4th ed., p. 76.}
• Zones based on an estimated maximum say nothing about the intensity at a client’s lactate threshold.^{6Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 579.}