The first thing to know is that the applications of heart rate training are often dependent on your experience as a runner and your goals as a runner. I often interact with at least three levels of endurance runners:
- The first time or inexperienced marathon runner
- The advanced/experienced marathon runner
- Ultra marathon runners
My advice would be for runners #1 and possibly #3 above to keep it pretty simple. There are some pretty precise and valuable things that can be done when advanced marathon training, but those things should really be done by experienced runners with sound training plans and possibly even coaches.
There are multiple "systems" in your body that ultimately determine how you will perform on race day. These systems are both specific to you and to your goals. As endurance athletes, one of the primary systems that we rely on is our aerobic system. Our aerobic system is what provides us with the steady state energy and helps us maintain a relatively long and constant ability to exercise. Inexperienced marathoners in particular should do lots and lots of aerobic training, possibly even their entire training cycle. This kind of training will help your body learn to burn fat as a fuel source. Even experienced marathon runners and ultra marathon runners will do many weeks (often 8 - 10 weeks) of primarily base building before they begin hard training. Another benefit of base building is that sets the foundation for your body to reap the rewards of hard training.
Avoid over trainingOver training is a serious condition that usually results in a runner being worn out and unable to train properly. If you spend too much time training at high intensities you could go backwards in your training. Or you could wind up injured. All running requires at least some recovery, but high intensity runs in particular can take several days. Recovery time is dependent on the race length, your age, and other factors. In general, the less experience you have and the smaller base you have, the longer it takes you to recover from a hard workout. Most advanced training programs do not have more than two key/hard workouts in a week. For example, it is common for advanced runners to have a speed workout and a long run each week. That is two key workouts. Sometimes a third key workout is added during key weeks or peak weeks along the week. Using a HR monitor helps to ensure that you are actually going easy when you intend to. Reading your heart rate can also tell you if your body is over stressed.
Ensure proper physiological responses to trainingYou don't run every long run at race pace because that would not training your body properly. The purpose of the long run is to get used to running for a long time, learning to eat and drink on the run, and helping your body to learn to utilize fat (instead of sugar) as an energy source. Run too fast on your long runs and you are likely to neglect almost all of the benefits above. Your body will rely too much on glycogen (sugar) for energy and won't learn to burn fat as effectively. Once again, using a HR monitor to ensure that you are training within a proper zone is an advantage to knowing you aren't going too fast here. (Some advanced marathon plans have a couple of "quality" long runs that allow you to train near race pace for a few miles as a test/preparation, but no plan that I have seen has one every week.) Conversely, if you are doing a key workout, then having a heart rate monitor will help you to ensure you have achieved the targeted heart rate zones.
Proper recoveryRecovery from hard workouts is important. However, recovery is different for all runners. Some, like myself, prefer to take days off or x-train in between hard workouts. Other runners like to run almost everyday and choose "recovery" runs to fill in the gaps. In either case, the idea is to keep these days very low in intensity and allow your body to recover (re-hydrate, rebuild muscle, replenish glycogen) from other hard workouts.
Good race strategyA common mistake that first time marathoners and ultramarathoners make is going out too fast. They underestimate how hard of an effort they can maintain for the given length of race. This results in rapid depletion of their primary energy source (glycogen), inability to properly take in additional fuel, and too much strain on the body. This often results in a crash that is very painful, hard, and unpleasant. In extreme circumstances or really long races, it can results in dropping out of the race. If you are familiar with your HR, then you can use that data and feedback to develop a proper pacing plan to ensure you have the best possible chance of completing the distance without a crash.
Track your fitnessOver time you can see your fitness improvements through data. For example, new runners and runners early in training cycles should find that they become faster running in the same zones while they are base building.
Determining Your ZonesDetermining your heart rate zones is somewhat technical and may require a little bit of trial and error (see my point about "observation only" below). I will not give you much detail here because it is a lot of math! You can read any of the sources below or Google the topic to find tons of information. Most of the zones are derived using formulas that are based off of deciding your max heart rate, which is an imperfect exercise. This process is worthwhile and necessary if you intend to do advanced training. If you'd prefer to keep it simple, I recommend the methods of Maffetone and Mittleman.
If you are an experienced runner looking to take your running to another level, then I recommend Peter Pfitzinger's book Advanced Marathoning.
Below is the table of workout zones outlined by Pfitzinger using my estimated maximum HR of 195.
|HR Targets (% of max)||Maximum HR 195|
If you are a new runner, interested in building a bigger base, or just a runner runner that likes to keep things simple, then I recommend reading the work done by Philip Maffetone and later added on to by Stu Mittleman. Here are my zones based on Mittleman's book:
|Speedy Aerobic Pace (SAP)||155||174|
|Most Efficient Pace (MEP)||144||154|
|Mostly Aerobic Pace (MAP)||124||153|
How to Use It
For base building, I recommend using Maffetone's work and keeping things simple. Run at your MAP or MEP for most of your miles, possibly even all your miles if you are an inexperienced runner. If you are using Pfitzinger's zones, then base building will be primarily done using Long Run, GA/Easy, and Recovery zones.