When trying to figure out the intensity of your workout, measuring one’s heart rate is one of the easier methods.  Measuring lactate levels in your blood isn’t typically a DIY activity.  We utilize smart watches, heart rate monitors, and fitness bands to easily display and track our heart rate during our workouts.  Your erg monitor can even display what your heart rate is right on the screen.  It is a fantastic way to determine if you are taking your workout to the intensity level that you want by referencing your current heart rate compared to your theoretical max heart rate.  
 
Recently described in an article by Life Hacker, some of these electronic heart rate monitors have a fatal flaw; specifically, the devices use an erroneous max heart rate formula of 220 beats per minute minus your age.  

The article referenced a New York Times interview with an exercise physiologist at the University of North Carolina.  The physiologist placed a heart rate monitor on a member of the US Rowing team, and as most rowers could guess, when this rower completed a 6 minute erg test, he held a pulse of 200bpm for almost the entirety of the test.  The rower, who was in his mid 20’s, should have had a max heart rate below 200bmp.  The traditional theory that it was impossible to reach your max heart rate and hold it for an extended period of time was just blown out of the water.

Determining your personal max heart rate turns out to be slightly more complicated than once thought.  There are now formulas that are slightly more accurate based on your sex and a percentage of your age.  To get the most accurate reading however, you are going to have to put in a little sweat equity and measure your heart rate when you push yourself to your max.  Next time you sit down on the erg for winter training, don’t always trust that the true max heart rate according to your heart rate monitor is correct.  

 
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• Age-Predicted Maximal Heart Rate