Recently for Zone 1-2 post I got a comment: “I would like to know how you and her managed this. My runs are almost always in zones 3,4 and 5 even allowing for heat and other factors”. As a coach, I am ask this question many times. First is to understand how your heart rate zones 1-5 are created. Did you do FTP test on the bike or Lactate Threshold field test on treadmill or use the new Kavoren formula or max heart rate formula? This is critical in determine how your heart rate zones are created. The most accurate way are the FTP test and Lactate Threshold field test on treadmill. The least accurate is max heart rate which is 220 – your age very generic. Many sport watches do that and some do the Kavoren formula adding your resting hear rate. Sarah and I did the FTP test on the bike then add 10 for each zone for the run. I tried the new Kavoren formula for Sarah but she was always higher. Where the FTP test is based on her current physiology and more accurate for her. Now you need to understand how your perceived exertion relates for each heart rate zone is critical too. I created a chart for my athletes using Borg Rate of Perceived Exertion (RPE), and feeling through breathing. Example of Zone 1 is hardly noticeable of the breathing. Example of Zone 2 is slightly noticeable of the breathing. When you run in the heat and/or up a hill your breathing will be harder and heart rate will be higher. Also, your running paces will be different for each zone. Sometimes just walking a bit or walk a hill on easy day will lower your heart rate. I hope this answered the question. If you have any question please reply to the blog. As a coach, I want to make you better athletes. Be safe and healthy!