Heart Rate

Our heart rate is like the tachometer of a car engine. How well it runs depends on the age of the car, the maintenance, and the quality of the fuel.

When training it is vital to monitor your heart rate. Are you idling, cruising or pushing the red-line?

Heart Rate Basics

There are 3 basic parameters you need to know for your own fitness: Resting Heart Rate (RHR), Maximum Heart Rate (HRmax) and Heart Rate Reserve (HRR).

Resting Heart Rate – RHR

Your resting heart rate can be measured after waking up in the morning but not when you’re active. The measurement of resting heart rate or pulse rate (the number of heart beats per minute) should be taken after a few minutes upon waking whilst still lying in bed. Give your body some time to adjust to the change from sleeping before taking your pulse (2-5 minutes). If you are not able to take a measurement first thing in the morning, make sure you lie down for at least 10 minutes before taking a measurement. Taking a radial or carotid pulse measurement (at the wrist or neck) is usually the easiest method.

Maximum Heart Rate – HRmax

  • Garmin calculates max heart rate by subtracting your age from 220 for males and 226 for females. (220-age) or (226-age)
  • Karvonen uses (220 – age) for maximum heart rate.
  • A study in 2001 with healthy adults found a more accurate formula of 208 0.7 x Age and no difference between male and female. See Tanaka, H., Monahan, K.D., & Seals, D.R. (2001). Age-predicted maximal heart rate revisited. J Am Coll Cardiol. Jan; 37(1):153-6.

We are going to use the latest method 208 – 0.7 * Age which is a bit more accurate for older people. So for example if you’re 40 years old:

HRmax = 208 - (0.7 * 40) = 208 - 28 = 180 beats per minute.

Heart Rate Reserve – HRR

Your heart rate reserve represents your full range of exercise levels. It is simply the difference between your max rate and your resting rate.

HRR = HRmax – RHR

This number is commonly used for calculating your target Karvonen heart rate for workouts. It’s a simple way to compute your target rates based on how long your plan to workout. However, for a complete training plan it is better to look at the zones and target your workout plan to emphasize time in each zone depending on your long term training goals.

Garmin Heart Rate Zones and Karvonen Training Zones

The first step towards understanding your heart rate and improving your fitness is to look at the following chart. Training ranges based on heart rate don’t take into account the individual’s anaerobic capacity, a trainable quality which shifts the anaerobic threshold higher.

Garmin uses the J.A. Zoladz method based on HRmax and Martti Karvonen method uses the Heart Rate Reserve for computing zones.

  • Karvonen calculation https://www.best-running-tips.com/heart-rate-monitor-training-karvonen.html
  • Garmin calc https://www.best-running-tips.com/heart-rate-monitor-training-zoladz.html
  • Also https://www.omnicalculator.com/sports/heart-rate-zone

Karvonen are percentages of heart rate reserve, not percentages of maximum heart rate.

Garmin HRmax%Karvonen HRR%Zone Name Dominate Energy SystemAbility to Speak
Zone 5
>90%ThresholdAnaerobic, PhosphateNo
Zone 4
>90%ThresholdAnaerobic, PhosphateDifficult
Zone 3
80%-90%Interval 1Anaerobic, AerobicStrained
Zone 2
75-80Interval 2AerobicShort Converse
Zone 2
70-75Utilization Training 1AerobicConverse
Zone 1
60-70Utilization Training 2AerobicRelaxed Converse
Table 1: Two methods used for categorizing heart rate workout levels

Measuring your maximum Heart Rate

Depending on your level of fitness, your heart rate zones could be much higher or lower than the formulas indicate. The gold standard for finding your maximal heart rate is a treadmill stress test in a lab, but you can simulate one on your own with a heart-rate monitor.

  1. At a track, do a warmup mile or two, followed by a mile at tempo pace
  2. Gradually increase your speed over 400 meters before running a final quarter all out.
  3. After every 100 meters during the last 400, look at your monitor and accelerate.
  4. The highest number on your monitor will be close to your maximum heart rate.