Monitoring Cardiovascular Exercise Intensity

Written by

June 24, 2014

A fantastic way to ensure you are getting the greatest benefit from your cardio exercise is to use a heart rate monitor. If you are still working on building exercise into your life and developing a consistent routine, you most likely need not worry about cardio intensity. But for those exercisers who are focused on taking aerobic fitness to the next level, or who love feedback and reinforcement, read on! 

Wearable biofeedback is now all the rage. Back in the day, heart rates were monitored by radial or carotid pulse count – remember checking your pulse in the middle of dance or step aerobics? Well those days are long over! There are now an abundance of gadgets and devices to choose from.

Some of the most popular brands on the market include Polar, Nike, Garmin, Wahoo Fitness, Addidas, Timex, Suunto, Mio and TomTom, and can be purchased at a variety of fitness retailers or online. Most monitors involve both a watch (receiver) and chest band (transmitter) but more and more are now watch only devices. There are even Smartphone apps where you can monitor directly from your phone! 

A new line of devices including Jawbone, Body Media and Fitbit monitor daily activity, sleep, caloric intake and caloric output among a variety of other data. As an alternative to heart rate monitoring most of these devices offer summaries of “vigorous” vs. “moderate” exercise activity. These devices have a cool “tech” look to them and are usually worn as a bracelet or armband.

My advice…

Comparative shop:

  • Price points range from $50 to $300 dollars for most devices so its helpful to have an idea of your budget in advance.
  • Determine exactly what you need and want in features to avoid getting overwhelmed.
  • Find out which companies have the best track record and which devices are the most reliable. Consumer Reports has a great listing!

Remember the old stand-bys:

  • If a monitoring device seems overwhelming, or if you are taking a Beta Blocker (which slows down the heart rate rendering it an unreliable measure of exercise intensity), use Rating of Perceived Exertion (RPE). Just ask yourself 0-10 “How hard am I working?” (equivalents are listed below) or use the Borg Scale (
  • You can also use radial or carotid pulse checks – start your count with a “zero” for accuracy.

My personal favorite:

  • I prefer monitors with fewer bells and whistles. The simpler they are, the more likely you will use it!
  • For years I have recommended the Polar Monitor Series. I use the FT4 both personally and for clients undergoing a Clinical Fitness Assessment.

Determining Your Target Heart Rate:

Step One – calculate your estimated Maximum Heart Rate

207 – (0.7 x age)

Step Two – determine desired level of aerobic intensity

*RPE equivalent 0-10 scale

50-70% light intensity 5-7 out of 10

70-80% moderate intensity 7-8 out of 10

75-90% high intensity 7.5-9 out of 10

85-95% very high intensity 8.5-9.5 out of 10

Step Three – multiply your estimated Max HR by the desired intensity

Example – 50-year-old individual seeking target heart rate zone for moderate intensity exercise

207 – 35 = 172

172 x .7 = 120 beats/minute

172 x .8 = 138 beats/minute

Target Training Heart Rate Zone = 120-138 beats/minute

**It is extremely important that you consult with your doctor and/or a fitness professional to help you determine the optimal intensity necessary for your individual needs and medical status**.

For individual questions you may contact Jody Miller at [email protected], or (301) 299-6586