There are numerous methods by which to gauge the effort of a run and potentially alter your pace accordingly. Here I’ll discuss the positives and negatives of using your heart rate.

 

Why measure heart rate?

The rate at which your heart is beating is a non-invasive and simple way to see improvements in fitness as your body adapts to the demands you place upon it through training. When not running, you can check your resting heart rate at a number of sites using nothing more than a stopwatch and your index and middle finger. Alternatively, nearly all modern running watches have an in-built heart rate monitor which will tell you your resting heart rate (RHR).

 

Why measure heart rate during a run?

When training for a specific event, we need to target various heart rate zones in different sessions to optimise our hard work and improve cardiovascular fitness. We use fat, carbohydrate and protein in different ratios depending on the body’s exertion level, which relates to heart rate. By tracking our heart rate, we can get an idea of and then control the ratio of fuels we use which can be an advantage for weight loss or sports performance.

Tracking your heart rate can also be used as a method to control your exertion during longer runs and races such as the marathon. If your heart rate gets too high too soon, you’ll be in a world of muscle soreness that’s almost certain to derail your race.

 

External factors

Dehydration, heat, wind and humidity all influence your body’s temperature in one way or another, which in turn can increase or decrease your heart rate. Without knowing how to account for these, heart rate becomes far less useful as a pacing tool.

 

Accuracy problems

Depending on the type of monitor used, you could end up with some serious differences in your actual heart rate and the reading given by the monitor you’re using. Several times my heart has felt like it was about to burst out of my chest at the end of a 4-minute-long, nearly maximal effort interval, only for my wrist-mounted heart rate monitor to say my heart rate is 140bpm. If you’re not familiar with heart rates, this is what I would expect if I were running significantly slower than my marathon pace.

Chest straps are another option and by all accounts, are slightly a more accurate. They can be very restrictive though, and for the extra little bit of accuracy I feel it puts me off more than anything.

Aside from the hardware issues, the calculations and algorithms used to estimate your target heart rate zones aren’t all that accurate either. (Check out my blog on the topic entitled “Why your heart rate zones are probably wrong”).

 

I know people who love monitoring their heart rate and have had success with it, but equally know people like myself who don’t find it offers them much value. It’s your choice and worth experimenting with if you can borrow a monitor from somebody before investing in one first. As always, test, monitor, evaluate, adjust, then start again.

Written by Kyle Brooks, Running Coach based in Norwich, Norfolk