By Bonnie Stein, M.Ed.
There is more than one way to know when you are walking or race walking in that optimal aerobic range called the target heart rate (THR) zone. Ideally, for maximum fitness benefits, we want to exercise in our own THR zone since this is the range in which exercise is safe and effective. Some methods are scientific and some are simple. All should help the walker keep the heart rate between 60 and 85% of the walker’s maximum heart rate (60-75% for beginners).
TALK WHILE YOU WALK
One method, called the "Talk Test" is the least scientific. It prevents you from exceeding your safe zone; however, there is no assurance that you will attain at least 60% of maximum. That means that if you rely only on the talk test, you may be exercising too gently to achieve the maximum benefits of your fitness program.
As the name indicates, the Talk Test means that during exercise, one should be able to carry on a conversation with some labored breathing, but never get out of breath. If you are huffing and puffing and can't keep talking to your exercise partner, assuming you have an exercise partner, you are going too fast.
The second way to determine whether one is walking or race walking within the THR zone is by a method called Perceived Exertion. A person exercising within the THR zone interprets his exercise as feeling "somewhat hard" in the level of exertion. If it feels very hard, he is probably exercising above his THR; if it feels easy, he is probably exercising below his THR. Perceived Exertion studies have proven to be quite accurate in the past with cardiac re-hab patients as well as athletes. Athletes especially are sensitive to determining their correct THR zone by employing this method. Given a sub-maximal stress test, using perceived exertion, I was able to guess when I reached my THR zone by utilizing the feeling of "somewhat hard." When the examiner took my pulse, sure enough it was at 75 % of my MHR.
TAKE YOUR PULSE, AND DO A LITTLE MATH
Another way of deciding when exercise is the most beneficial is by taking one's pulse. If you do a little preliminary math using the Karvonen formula for figuring out your THR, you can predetermine where your pulse should be when you are exercising aerobically. Start with 220, subtract your age, subtract your resting heart rate, multiply by 60-85%, then, add back in your resting heart rate.
This may sound somewhat complicated if your favorite subject is not math. Yet, the Karvonen formula is more accurate than the old formula which left out the individual's resting heart rate. The negative features about this method are that some people have a difficult time finding their pulse, you must stop to get a pulse, heart rate slows rapidly after stopping exercise so you get an inaccurate reading if you wait too long, and by the time you take your pulse your exercise bout is usually over for that day which means that you can no longer alter the intensity of that exercise. Also, some people don't like the math computation that is necessary.
Remember that the heart rate charts on the wall in aerobic dance studios and exercise facilities are based on the older method which did not take into account the individual differences of resting heart rate. Covert Bailey, the author of the popular FIT OR FAT series, says that method is accurate for only about 60% of the population. That means that 40% of us need a more accurate manner of heart rate determination.
THE BEST WAY
The most accurate way to measure intensity of exercise is by continuous measurement with a heart monitor. When I started racewalking in 1984 a wireless heart monitor was not in the affordability range for most of us. Precise heart rate monitors were only found in hospitals or exercise physiology labs and the cost could exceed thousands of dollars. Wireless heart monitors for exercisers have become available and affordable. The best types are those which have a chest band with a sensor/transmitter attached and a wrist monitor. Be wary of the type that have a device which attaches to the ear or to the fingertip. They have not proven to be as accurate as the chest band monitors.
I recommend those made by Polar. Polar monitors are as accurate as an EKG reading (not true of many heart rate monitors.) You can program in the upper and lower limits of your own target heart rate zone. The monitor beeps when you're above or below your range, telling you when to work harder or when to ease up.
The Polar monitors are available locally and on the Internet. The retail cost starts around $50 for a very basic model and goes up to a few hundred dollars. All have the same chest band and sensor/transmitter. The high end Polars can communicate with your computer. They won't wake you up in the morning to get you out to racewalk, but they'll do most anything else.
Racewalking for fitness can be a fine cardiovascular workout for most people provided that you learn how to racewalk in your personal target heart rate zone. Any of the methods above will help you accomplish your fitness goals. Pick an exercise you like or experiment with a few different exercises. Remember, running is not better than cycling, racewalking is not better than swimming. The exercise that is best for you is one which you will stick with, one in which you will not get injured, and one that you will do at least 3-5 days a week. Most importantly, one in which you stay within your target heart rate zone. See you there!