Heart rate and training zones
Athletes often ask how to use heart rates in training. I would like to write a simple article however I believe that heart rate zones are not always the best option and should be used in conjunction with other zone indicators.
Saying that, heart rates zones are not a bad guide to help you determine your pace for a training session designed to be in a certain “zone” for running and cycling. By maintaining your heart rate within certain parameters, you can target session goals and be reasonably confident you are on the mark.
For example an aerobic long run is normally at zone 2 or below. Maintaining your heart rate below the zone 2 limit indicates that you have met your goal for an aerobic session.
There are different methods for setting zones. Some people prefer the method of using % of maximum heart rate. Jack Daniels, running guru, suggests this as a method in his book The Running Formula.
Alternatively, Joe Friel’s method involves testing to obtain the lactate threshold heart rate then setting your heart rate zones based on percentage of HR lactate threshold.
Lactate threshold is the tipping point, where your body can still produce enough oxygen to use the lactate in your system, lactate being an alternative energy source for your body. At a higher heart rate you can no longer obtain enough oxygen to keep up with lactate production and in order to clear lactate from your body, you need to slow down or stop.
The limitation I find with using the heart rate zone method is that it can affect the quality of some training sessions. I’ll explain.
If you are running 4-5 threshold intervals at HR zone 4, then it is going to take some time to get your heart rate into the zone. You are likely to run extra hard in the first couple of intervals. The issue with this is that your first couple of intervals are going to be extra fast but the last 3 intervals are likely to suffer because you have spent all your energy going too hard, too early. Quality, therefore decreases as the session goes on.
My preferred approach is to use pace zones in conjunction with heart rate in running and rate of perceived effort (RPE) in conjunction with heart rate with cycling. Pace zones can also be calculated using the Joe Friel method, where FTP is the functional threshold pace.
You can read more about the Joe Friel Method on the training peaks site. More importantly, come and talk to one of your friendly club coaches!