Maximum Heart Rate (220 − Age)

Maximal heart rate is estimated with the formula:

Maximum heart rate (Max HR) = 220 − Age

This estimated maximum is the reference point from which cardiorespiratory training intensities are derived. The ACSM intensity prescriptions express the target as a percentage of this maximum — 60% to 90% of maximal heart rate (Peterson & Bryant, 1995), or 55/65–90% of maximum heart rate in the ACSM 1998 position stand. To find a working target heart rate, the chosen percentage is applied to the Max HR value.

220 − Age (Fox et al., 1971) remains the most widely used estimate for its simplicity, but it carries a standard deviation of roughly 10-12 bpm around the true value -- a meaningful margin of individual error. Regression equations from larger, more rigorous samples -- most commonly Tanaka, Monahan & Seals (2001): Max HR = 208 − (0.7 × Age) -- are now generally considered more accurate on average, especially for older adults, where 220 − Age tends to underestimate true max HR. Either formula is an estimate; a direct graded exercise test is more precise when accuracy matters. See verification_note in this module's frontmatter.

• Max HR = 220 − Age (age in years).
• Used as the basis for percentage-of-max-HR intensity targets.
• Training intensity range expressed against this value: 60–90% (Peterson & Bryant) or 55/65–90% (ACSM 1998).
• 2026 update: 220 − Age has a ~10-12 bpm standard deviation of individual error; Tanaka et al. (2001) 208 − (0.7 × Age) is generally considered more accurate on average, especially for older adults (220 − Age tends to underestimate their true max HR). Neither replaces a direct graded exercise test.

• cardiorespiratory-guidelines — intensity prescribed as 60–90% of this value.
• acsm-exercise-recommendations — 55/65–90% of this value (and the VO2-reserve alternative).
• target-heart-rate — applies the percentage to Max HR to get a beats-per-minute target.
• beginner-hr-note — the source's "220 bpm – 192 bpm" beginner note.