Cardiovascular fitness has a huge impact on your speed as a runner ... and on how long you’ll live and how much you’ll enjoy later life. Logically, heart rate is an excellent indicator of cardiovascular fitness, and any heart rate monitor measures heart rate.
So how do you choose?
The important thing in choosing an HR monitor is knowing what you want to do with heart rate data, and whether a particular HR monitor provides it to you in the form you need. The various uses for heart rate, and a list of HR monitors that support each use, are shown in a link.
Yeah, okay, price is important too, but you're on your own to find the best price for a watch that supports what you want to do. Just type the name and model into a search engine and you'll be swarmed with price listings. How easy an HR monitor is to use is important as well. My take is that no advanced HR monitor is easy to configure and use if you’re limited to the array of buttons on the watch itself. Look for and use the configuration software that lets you set up everything on your computer screen and transfer settings to the watch.
This post assumes that you already know or can learn about using heart rate zones from the manual of the heart rate monitor you buy or from this, the best summary I’ve found on heart rate zones. You'll also need to know how to measure or calculate maximum heart rate.
Heart rate at rest (Click for List). Resting heart rate may seem unexciting, but it's one of the most useful functions and any HR monitor can do it. I’ve even worn my chest strap and HR monitor to bed in order to get a truly accurate take on my heart rate at rest (you should measure when you first wake up and before you move from horizontal to vertical).
Once you have a benchmark reading of your resting rate, try to check it every morning. Over time, it should gradually decrease. Lance Armstrong’s is 32 to 34. An average male of the same age has a resting rate of 70. That means Lance’s heart pumps approximately twice as much blood per beat as an average male’s heart. Mine gets into the low 40s when I’m in peak condition. Use something (a paper running diary, a PC-based program that might come with your HR monitor, or an online running diary like those provided by dailymile.com or mapmyrun.com) to record your resting rate along with how you feel before and after a run.
Watch for a rise in resting rate the morning after hard workouts, or on days when you feel tired. If a resting rate spike persists more than a few days, you are probably overtraining and might want to take a day or two off or do a higher percentage of easy miles.
Pacing your runs (Click for List). A watch that simply displays your current heart rate could be used to pace your runs. I suppose you could also try to hold two fingers to your wrist and catch the number of beats while you simultaneously count to ten while running. To make run pacing practical, a watch needs to beep “too high” and “too low” warnings when you’ve passed out of your target zone. No need for different tones. Believe me, you’ll know when your watch beeps whether you’re going too fast or too slow. The beep plus a little bit of guilt is great inducement to quicken or slow your pace.
Tempo or threshold running to improve performance (Click for List).The most effective technique I know for improving marathon performance is tempo or threshold-pace runs. While you don't necessarily need a heart-rate monitor to find the right pace (see this post for more info), a heart rate monitor is the most fool-proof method.
Average heart rate for total run (Click for List). While average can be misleading, particularly if you had many waits at cross roads or other reasons to stop, your average HR for a run is a good rough guide to how hard you worked your cardiovascular system. Put another way, it’s a better indicator of how hard you ran than your time, which can be impacted by hills, wind, temperature, and your current conditioning.
With a measured distance and the stop watch function of all HR monitors, you can record the average heart rate as part of a log of run name or location, distance, and time and you’ll see how your heart rate compares as you run across the same terrain and distance a number of times.
Average heart rate
for a split (Click for List). An HR monitor with a
split function is a great way to see how you’re doing during a race that has
mile markers. A lap function (available only from heart-rate monitors that also measure distance run) eliminates the need to run a marked course and click at each marker. Beyond knowing that you’ve
hit a particular pace for the last split or lap (say, a mile), your heart rate indicates something
about your fatigue. For example, if you go out too fast you’ll see your heart
rate climbing from mile to mile even though you're merely holding a steady per-mile pace. Eventually, your heart rate will go into the
unsustainable anaerobic zone where you’re building oxygen debt and will soon
have to slow down.
You can also tell something about what’s slowing you down at the end of a race. I’ve had joint discomfort in a few marathons before I discovered glucosamine/chondroitin where I was pained enough to be unable to keep my pace and heart rate high, thus finished with a disappointing time. In contrast, after hitting the wall before I discovered the secret to carbo loading, I had my heart rate climb near maximum while my pace slowed to a very tired jog.
Heart rate in relation to instantaneous pace, elapsed time, and distance (List). To compare the moment-by-moment change in heart rate versus how fast you are running, you really need 2 things: the ability to upload data to a computer and a monitor that somehow measures the distance you’ve run.
There are two ways to measure distance and combine that data with heart rate data: 1) adding a GPS or 2) foot pod function to an HR monitor.
A GPS uses satellites to calculate changes in your position and can combine that movement data with heart rate data from a chest strap. This is the most accurate and easiest method.
A heart rate monitor that includes a foot pod sensor has some advantages and disadvantages over GPS. Such sensors calculate running speed, distance covered and even altitude change using an inertial system that sits on your shoe and senses foot movement. With a single calibration run, you’ll find a food pad’s accuracy rivals that of a treadmill or a GPS. Unlike a GPS, closely spaced tall buildings in big cities, a canopy of trees, or the walls of a canyon don’t keep a foot pod from working.
In comparison, a GPS tends to be even more accurate without calibration, can display your run on a map with the appropriate website connection (useful for sharing favorite runs with others easily), and can help you find your way home if you run on unfamiliar trails or in unfamiliar cities).
Interval Training (List). A few advanced HR monitors guide you through interval training. You don’t need a track to run intervals if your watch can take you through sets of sustained effort for a given amount of time at a target heart rate. An HR monitor that measures distance travelled can be set to take you through a set of mile repeats and tell you where your heart rate climbs to as you strive to hit target times for each mile you run. You can also use heart rate recovery as the trigger for setting off on the next interval. Some watches even include a countdown timer when it’s time to take off again, and put in a cool down interval. It’s almost like having a coach.
Gauging fitness with recovery rate (List). In my experience, few people who use HR monitors tap this great method of gauging fitness. While heart rate at a given level of exertion is an excellent indicator of fitness, you need to control a number of factors to know exertion level was really the same. Not so with the passage of time, and the fitter you are the faster your heart rate should fall when you come to rest after exertion. The usual metric is how far your heart rate falls in the first two minutes after peak exertion, and you’re looking for a drop of 25 or more to indicate excellent fitness.
While you can time and calculate recovery rate yourself, you’ll get a more accurate reading and do it more regularly if your HR monitor handles it for you automatically.
A number of HR monitors offer such automated fitness tests. For example, Polar units including the S625X, for example, estimate your maximum aerobic power and maximum heart rate as part of a Polar OwnIndexValue. While only laboratory tests can do an accurate VO2 Max (via a tube measuring your highest level of sucking wind during strenuous exercise on a treadmill), measures like this are a great way to track your cardiovascular fitness over time.
Other Features To Look For. This is by no means an exhaustive list, but while you're browsing the watches that handle the uses you want to put an HR monitor to, the deciding factor may be one of the following advanced features:
- Large memory. Most advanced devices can record data from more than one run or bike ride. If you rarely upload data for analysis, this might be useful. Another advantage of large memory is your have lots of room to record data more frequently. If you record heart rate and pace every 5 seconds as opposed to once a minute, you'll see the ups and downs and stops and starts that minute as opposed to an average heart rate and pace.
- Ease of upload. HR Monitors that use bluetooth to automatically upload data when you come within range of your computer have a certain appeal. In general, methods that use proprietary holders and serial ports or audio transmission of data tend to be more trouble than HR monitors that connect via a more modern USB cable.
- More complex analysis and reporting. Some HR monitors routinely record and report min and max heart rates, overall averages for a number of runs, and probably a whole lot of other things. Comment if you find something really useful that I've left out.
- Coded signals. I've run in a number of marathons with a variety of HR monitors without encountering interference, but maybe that's just because I've always owned devices with coded signals, which eliminate the problem.
- Biking options. A wheel sensor for rotations to measure distance and special handlebar mounts are a couple I remember that might matter to tri-athletes or others who train regularly on a bike
Bottom line: Heart-rate monitors are the geekiest running aid I know. You may find that a simple GPS running watch or an iPod with the Nike foot sensor are more to your liking (see my overview for choosing among the options). But if you're a serious runner who wishes to avoid under- or over-training and, ultimately, to run faster and longer at a lower heart rate (i.e., to get in better shape and verify that you have), one of the dozens of available heart monitors is going to be just the thing to keep you motivated and running.