Remember when you bought that fancy GPS watch and it came with this strange little strap much too large for your wrist? You may have just chucked it back in the box. Wait, that was just me??? Kidding – sorta.
A heart rate monitor (HRM) can be a useful tool in your running arsenal if you learn how to use it to your benefit. By tracking your heart rate through use of a HRM, you can determine how hard your heart is working – or not working. Knowing your optimal training zones can help prevent over-training and also training too easily.
When training using a HRM, your aim is to train within various “zones” depending on the type of workout. Many of us work too hard during our “easy” runs which can result in injury and symptoms of over-training. By learning your specific target zones, you can better monitor your response to your training runs. Training within the proper zone is also felt to teach the body to run more efficiently by using fat for fuel versus carbohydrates. If you continuously push yourself too hard in training, your body resorts to using quick carbohydrate reserves rather than fat for fuel.
The zone in which you will train is determined by the goal of the workout.
- Zone 1 (60-70% of your heart rate reserve) is used for very comfortable paced runs, such as warm up or cool down, or long, slow runs.
- Zone 2 (70-80%) is where the majority of your runs will fall and is considered the “aerobic zone” and your target heart rate zone. You can carry on a conversation in this zone and training in this zone is most effective in improving your cardiovascular system.
- Zone 3 (80-90%). This effort is “comfortably hard” and you won’t be able to talk for more than a few phrases or sentences. You have entered the anaerobic zone in which your body can no longer remove lactic acid as quickly as it is produced. Training in this zone improves your lactate threshold and overall performance.
- Zone 4 (90-100%). Most similar to your 5k effort and not exactly a “training” zone for most mortals. Unless you are very fit, you should not work in this zone for very long. This is hard and you can sustain it for only 20 seconds or so at a time. You can only speak in single words or very short phrases. The benefit to training here is to improve the efficiency of your fast twitch muscles which can increase your speed. (source, source)
In order to train using heart rate, you will need to determine your maximum heart rate and your resting heart rate. Maximum heart rate can be determined in a couple different ways. You can use the formula 220 minus your age but this isn’t accurate for many people. Using heart rate reserve is another way to determine your maximum heart rate. For this, you will need to do a 2-mile time trial (after at least a 1-mile warm up) while wearing your HRM. You’ll take the highest recorded heart rate during your 2-mile run at about your 5k effort. Your heart rate reserve (HRR) is this max number minus your resting heart rate (your pulse at your neck or wrist as soon as you wake up and before you get out of bed in the morning). The training zones you should aim for are determined by multiplying the percentage for a given zone by your HRR and then add back in your resting heart rate. Runners World Magazine has an excellent example on how to calculate these number here.
Just like your training plan, goal paces, hill work, strength- and cross-training, and long slow runs, use of heart rate training is one more technique to help you get the most out of your running. It can help you train at the correct intensity and may prevent over-training and injuries. Have you used your HRM lately?