Many coaches use a very wide array of confusing heart rate (HR) zones. You’ve seen them I’m sure: 1, 2, 3, 4, 5a, 5b, 6….etc. All of these ranges represent various intensities of training and are meant to elicit a certain physical response. What I find is that:
1) Any HR over anaerobic threshold is best used for track repeats, etc. and is very difficult to monitor and stay steady at. While running 5 or 6-minute miles around a track, the last thing you want to be doing is looking down at your watch trying to figure out if you are in the right HR range. You’ve got bigger problems like thinking about form, and how not to throw up. These areas are better trained without an HR monitor and instead with a focus on performance indicators such as speed, wattage, etc. The various intensity zones can be addressed with varying length intervals done at best sustainable effort. These should be chosen based on race distance and get more race specific as race day gets closer. Just get good and tired and the workout will be effective. The added focus on performance will drive progress.
2) HR rate ranges below TH are useful to help keep athletes capped at aerobic intensity zones. This method is much better than the pace or wattage method since as improvements occur, the body adapts to the workload by producing a lower HR at the same pace. Because of this, the pace is increased by the athlete to stay in the HR zone. This allows the workload or stress on the body to increase and continue to elicit a positive response from the training. With pace only, as the body adapts, the pace stays the same and therefore results in a reduced relative workload. The only way for this to work is very frequent testing to help keep the ranges up with the fitness of the athlete but still won’t be as real time as the HR method. The other issue with pace defined ranges versus HR defined ranges is that the athlete has no reason to focus on efficiency. If I tell a pace defined athlete to run his zone 1 8:00 m/m pace, that’s what he is going to do. He may have arms flailing around, etc. If I tell the same athlete to run at his zone 1 HR range of 140-150 bpm, he’ll do everything he can to go as fast as possible in that range. This includes relaxed breathing, loose shoulders, etc. These are all good things that promote efficiency.
3) The HR zones used below threshold don’t need to be overly complicated. In fact, 3 zones is all I typically recommend; one recovery, one base work, and one tempo. More than this and an athlete is more likely to get confused and not follow or drop the whole process. No matter what, consistency and compliance with the program is the most important piece of athletic progress. Anything that undermines these, even if totally scientific, should be avoided like the plague.
4) Most athletes don’t have accurate enough threshold data to make ranges in such minuet detail. In my experience getting athletes from other coaches, TH heart rates and therefore ranges can be extremely wrong depending on the frequency of testing, the type of test, and the person operating the test. Because the TH heart rate can be off by as much as 10 beats from these tests, it is crazy for these coaches to have six heart rate zones defined in 8 beat increments. The operator of the test is probably the most important aspect of proper heart rate zones. An experienced coach can get TH heart rate fairly close with almost any piece of data or test protocol assuming its accurately recorded. Also, the whole process of identifying an HR for threshold is indirect. They are not linked to one another as many think. All we try to do is find the HR we happen to be at when our body begins to use the glycolic system at a much larger percentage. This is convenient since HR is easy to monitor during exercise.