There are two popular general equations for calculating target heart rates: Age
Adjusted and Karvonen. In addition,
two alternative equations are presented here, Heart Zones and Inbar. Age is the key factor in each of the heart rate equations. Typically, age is subtracted from a fixed number to determine your maximum
heart rate. Choose the method you are
most comfortable with. The following
is a brief description of each equation presented on this page:
Age Adjusted = (220-Age) * % of Max
You’ll notice that this equation is very simple and can be easily memorized. Unfortunately, it can also have large
prediction errors, oftentimes greater than 10 bpm.
Karvonen = ((220 - Age - Avg. Morning
Resting Heart Rate) * % of Max) + Avg. Morning Resting Heart Rate
The heart rate calculated in the Karvonen method is a more personalized figure closely
tied to your fitness level. It follows
that your resting heart rate is unique to your body and essential to determining
your maximum heart rate. Find your
average morning resting heart rate by measuring your pulse in the morning before
you get out of bed.Do this for several
mornings in a row and determine your average.Every few weeks or so, reacquire your average resting heart rate as it will
change with your training efforts.
(The Karvonen method is named after Dr. M. J. Karvonen who did research in the concept
of heart rate reserve and published the results in 1957.)
Heart Zones® (Male) = ((210 - (0.5 *
Age) - (0.1 * Body Weight)) + 4) * % of Max
Heart Zones® (Female) = ((210 - (0.5
* Age) - (0.1 * Body Weight)) + 0) * % of Max
The Heart Zone® method was developed by Sally Edwards, exercise physiologist and
founder of Heart Zones® Training System.
Sally Edwards is also a professional athlete and former Master's World Record holder
in the Ironman Triathlon. The Heart
Zones® equation takes into account an individual’s body weight and gender. The equation factors in a slight decrease in heart rate for every unit increase
in body weight. In addition, a slight adjustment is made to account for the differences between male and female body composition.
Inbar = (205.8 - 0.685 * Age) * % of Max
Based on the results of study by Robergs, the general equation for maximum heart
rate proposed by Inbar is the most accurate.
Or, as Robergs says, the least inaccurate.
Through extensive research into the details of 43 different maximum heart rate equations,
Robergs concludes that all methods, including Age Adjusted and Karvonen (Heart Zones®
was not studied), have error margins that are unacceptably large. However, he points
out that the margin or error using the Inbar equation
is the lowest at +-6.4bpm.
Gulati = (206 - 88% of Age)* % of Max
This peak heart rate formula was published in the journal, Circulation, in 2010. Martha
Gulati, M.D., studied the heart rate response to exercise stress tests among over 5,000 women. Gulati determined
that the basic Age-Adjusted formula resulted in peak heart rates that were too high for women. The Gulati
formula corrects for the female gender as well as age.
Heart Rate Monitoring
Heart rate monitoring is essential for maximizing the effectiveness of your training. Your heart rate gives you a gauge to
quantify how much effort your body is putting into a workout. Too many factors can interfere with your mind’s ability to subjectively measure
The easiest way to begin heart rate training is to purchase a heart rate monitor
(HRM) from your local or online sporting goods retailer. Read the instructions and strap the monitor on before your next workout. The more you use the HRM the more you
will develop a sense of how your heart beats throughout various stages of your workout.
You should know your maximum heart rate to establish boundaries during training. Most recommendations suggest targeting
a heart rate between 55% and 85% of your maximum heart rate for a period of time,
say 30 minutes, to build your aerobic base.
50% - 60% = Beginner or Recovery Zone.
Maintaining a heart rate in this zone is ideal for comfortable exercise to improve
overall health. Start here if you are new to exercise or are in need of a recovery
day between intense workouts. It is also a good zone for overweight people to begin
burning fat. The effort level is low and allows time for the muscles and joints to wake
up and prepare for a more active life.
60%-70% = Heart Health and Weight Loss Zone.
If you get “winded” walking up a single
flight of stairs, start training in this zone. With your heart beating between 60%
and 70% of your max you are conditioning it to pump more blood. Better circulation
efficiency is the key to delivering more oxygen to your muscles. Stored body fat
is the primary fuel in this zone. Your long, slow, distance workouts are in this
level – with emphasis on slow.
70%-80% = Aerobic Zone.
If you can’t run the soccer field like you used to, it is probably because you are not spending
enough time in this zone. Training in the aerobic zone will improve cardiovascular fitness. Your body will more effectively transport oxygen-rich blood to your muscles.
Your 30-mile road ride will begin to take less time. Your 10k’s will improve, etc.
80%-90% = Anaerobic Threshold Zone.
When your heart is beating in this range, your body is producing lactic acid at
levels it cannot effectively remove.
Sprint workouts are designed to push your anaerobic threshold. Training in this zone conditions your body to tolerate lactic acid for longer
periods of time. This will lead to
muscle growth and significant improvements in athletic performance.
90%-100% = VO2 Max Zone
VO2 Max is your body’s maximum oxygen
consumption level. It is measured in volume/time units. You may reach this zone only for very short bursts of time. When you go into oxygen debt by racing
your buddy to the finish line you have reached your VO2 max. Your lungs can’t keep up your body’s demand for oxygen and lactic acid floods
into your muscles. Training in this zone increases enzymes in your muscles responsible for anaerobic metabolism.
Edwards, Sally. Heart Zone Training System, www.heartzones.com.
Inbar, O. Oten, A., Scheinowitz, M., Rotstein, A., Dlin, R. and Casaburi, R. Normal cardiopulmonary responses during incremental exercise in 20-70-yr-old men. Med Sci Sport Exerc 1994;26(5):538-546.
Karvonen, M.J., Kentala, E. and Mustala, O. The effects of training on heart rate: a longitudinal study. Ann Med Exper Fenn 1957;35(3):307-315.
Robergs, Robert A., and Landwehr, R. The Surprising History of the “HRmax=220-age” Equation. Journal of Exercise Physiology 2002:Vol 5, Number 2.
Gulati, Martha, et al., Heart Rate Response to Exercise Stress Testing in Asymptomatic Women. The St. James Women Take Heart Project, Circulation, 2010