Age-Predicted Maximal Heart Rate Revisited
Hirofumi Tanaka, PHD, Kevin D. Monahan, MS, Douglas R. Seals, PHD
Boulder and Denver, Colorado
OBJECTIVES We sought to determine a generalized equation for predicting maximal heart rate (HRmax) in
healthy adults.
BACKGROUND The age-predicted HRmax equation (i.e., 220 2 age) is commonly used as a basis for
prescribing exercise programs, as a criterion for achieving maximal exertion and as a clinical
guide during diagnostic exercise testing. Despite its importance and widespread use, the
validity of the HRmax equation has never been established in a sample that included a
sufficient number of older adults.
METHODS First, a meta-analytic approach was used to collect group mean HRmax values from 351
studies involving 492 groups and 18,712 subjects. Subsequently, the new equation was
cross-validated in a well-controlled, laboratory-based study in which HRmax was measured in
514 healthy subjects.
RESULTS In the meta-analysis, HRmax was strongly related to age (r 5 20.90), using the equation of
208 2 0.7 3 age. The regression equation obtained in the laboratory-based study (209 2
0.7 3 age) was virtually identical to that obtained from the meta-analysis. The regression line
w
CONCLUSIONS 1) A regression equation to predict HRmax is 208 2 0.7 3 age in healthy adults. 2) HRmax
is predicted, to a large extent, by age alone and is independent of gender and habitual physical
activity status. Our findings suggest that the currently used equation underestimates HRmax
in older adults. This would have the effect of underestimating the true level of physical stress
imposed during exercise testing and the appropriate intensity of prescribed exercise programs.
(J Am Coll Cardiol 2001;37:153– 6) © 2001 by the American College of Cardiology
Maximal heart rate (HRmax) is one of the most commonly
used values in clinical medicine and physiology. For example,
a straight percentage of HRmax or a fixed percentage of
heart rate reserve (HRmax 2 heart rate at rest) is used as a
basis for prescribing exercise intensity in both rehabilitation
and disease prevention programs (1,2). Moreover, in some
clinical settings, exercise testing is terminated when subjects
reach an arbitrary percentage of their age-predicted maximal
heart rate (e.g., 85% of HRmax) (3). Maximal heart rate also
is widely used as a criterion for achieving peak exertion in
the determination of maximal aerobic capacity (1,4,5).
Because maximal exercise testing is not feasible in many
settings, HRmax is often estimated using the age-predicted
equation of 220 2 age. However, the validity of the
age-predicted HRmax equation has not been established,
particularly in a study sample that included an adequate
number of older adults (e.g., .60 years of age). The latter
limitation is crucial in that older adults demonstrate the
highest prevalence of cardiovascular and other chronic
diseases. As such, this is the most prevalent population
undergoing diagnostic exercise testing, representing a key
clinical target for exercise prescription. Importantly, older
adults are a population in which there is often a reluctance
or an inability to measure HRmax directly, owing to concerns
related to the physiologic stress imposed by strenuous
exercise. Thus, ironically, the 220 2 age HRmax prediction
equation is used in this population more than in any other.
Accordingly, the aim of the present study was to determine
an equation for predicting HRmax in healthy, nonmedicated
humans ranging widely in age. To address this
aim, we first used a meta-analytic approach in which group
mean HRmax values were obtained from the published data.
Subsequently, we cross-validated the newly derived equation
in a well-controlled, laboratory-based study. With each
approach, we attempted to establish the generalizability of
the equation by determining whether gender or habitual
physical activity status exerted a significant
. What happens if I am over or under some? Let's say my target is 130. What happens at 120? 140? What if I am at 120 one day and 140 the other?
