I have been running and competing in triathlon since 2009 and in the first few years I used a chest HRM but found it unreliable and mainly used to only look at the data after a run or ride and not monitor during, after that I ran to feel – it was only in the last few years that I re-found the love for heart rate training. 

Recently HRM’s (Heart Rate Monitors) appear to be much more reliable and with the rise in smart watches they have become a daily monitoring system for many more people, with most smart watches having an optical HRM built in. Optical HRM’s are great for monitoring sleep, and daily use but if you want to monitor heart rate in real time whilst running or cycling then a chest HRM is the way to go, these are much more accurate and generally show actual HR rather than jumps in HR that the Optical sensors can.  

So why not just run to feel ? I have found that a comfortable run speed and even cycle speed was generally in the Zone 3 heart rate zone – Zone 3 is neither a high/hard effort or an endurance based effort therefore its somewhere in between, working in this zone doesn’t make huge improvements, but does feel comfortable. To work on endurance heart rate needs to be lower and generally in Zone 2, this increases fat burning capabilities and less reliance on carbs for fuelling, it builds aerobic base capabilities and allows you to be active for longer without “blowing up”. Working in Zone 4 works the body hard and helps to increase speed endurance and improve your lactic threshold, this coupled with Zone 5 work can improve overall speed but should only be done for limited periods.  

If you want to improve to be faster or run longer then you need to improve the engine and your heart is where it starts, get the heart working in the right zone and reap the rewards, generally look at working in Zone2 for at least 80% of the time then leave the hard work in Zone 4/5 for less than 20% - staying away from the comfortable Zone 3.  

The majority of my runs are kept under 75% max HR as is my bike, what this means is that I have to slow down on inclines to keep the HR down, on days where I complete intervals or “efforts” these are generally minimum but are hard efforts above 85% max HR for the duration of the interval, with recovery back to below 75% - This is very similar to the MAF (Maffetone method) where you use a simple calculation to work out what your MAF heart rate should be and work to that. MAF is more than just a calculation it is a lifestyle change, moving away from fueling with carbohydrates and working on fueling with fat – this is kinder to the gut and means less stomach issues when you race hard.  

More about MAF to come