Heart Rate Training Part I

by Kevin Polansky

March 5, 1993

Taking and using your heart rate

For years, American swimmers and swimming coaches have been asking the questions "How much is enough?" and "How much is too much?" Even today's adult fitness swimmers are in search of optimal training methods that will deliver the greatest physical benefits. Likewise, endurance athletes in all sports have long been in search of a reliable monitoring system that would guide them to "smart" training.

Testing the blood for lactic acid concentration has proven to be the most reliable method for determining the effect of training on our bodies. This method, however, proves to be impractical for most adult swimmers simply because of the expense and the advanced equipment required.

Currently, the most practical method for measuring training effect is using a heart rate monitor (HRM). This device is capable of measuring your heart rate continually during the course of exercise. Following the exercise, your heart rate can be plotted on a graph using computer software to show levels of exertion. A typical HRM consists of a wrist monitor, a chest band, and a sensor/transmitter that straps around the chest. The most widely used water-proof monitor on the U.S. market that can be used for swim training is made by POLAR CIC, Inc.

HRMs can be beneficial for both the elite competitive swimmer and the recreational swimmer. Kieren Perkins of Australia, current world-record holder in the 800 meter and 1500 meter freestyles, uses a heart rate monitor in virtually all training sessions. For swimmers with heart conditions or those labeled "lap swimmer," the monitor keeps a close and accurate measurement of pulse during exercise. Author Sally Edwards, in The Heart Rate Monitor Book, says "being the best isn't as important as being your best, and heart rate monitors can help you get there."

So you might be asking yourself, why do I need to strap this equipment around my chest? Why can't I use a pace clock and count my own pulse at the end of a set or an interval? Unfortunately, this quick-check method for monitoring your heart rate is quite inaccurate. Research has shown that an athlete can be off by as many as 17 beats per minute using this method -- a huge discrepancy! Also, as you count for more than five seconds after you finish a swim, your heart rate will start to drop in proportion with your fitness level.

In the brief time that I have used a heart rate monitor, I have found that getting back into aerobic shape has taken on a new meaning in my training. With a heart rate monitor, I do little or no guessing in my workouts as I know specifically what type of effort I am putting forth. Training by the "hit or miss" method or by our own "feel" for what our coach thinks we need may be a thing of the past. It is highly likely that the use of a HRM will produce a more scientific training regimen for all levels of Masters swimmers.

So, you may ask, what does the HRM do to help enhance your training? Your heart is the "engine" of your body. Much like the tachometer in your car, the monitor tells you just how hard you are working. The HRM gives you hard-line biofeedback, concrete evidence that can cut through misleading feelings, thoughts, and perceptions.

Many heart rate trainers and coaches have stated the reason why a lot of athletes don't show greater improvement is because they do not effectively train the appropriate energy systems. As stated later in this article, the energy system used is determined by the heart rate sustained over a period of time. Maintaining a relatively low heart rate will train aerobic energy systems while maintaining a higher heart rate will train the anaerobic energy systems. The monitor can give immediate feedback as to which energy system is being used, and it gives the swimmer the opportunity to make an adjustment in training pace to meet workout objectives.

In order to begin applying this tool to benefit your training, you must first determine your resting heart rate (RHR). The RHR can vary by as many as 50-60 beats per minute between two people of the same weight, height, and age, though for trained athletes the difference is usually much smaller. RHR's also vary between sexes: on average, a female's resting heart rate is roughly five to seven beats per minute higher than a male's heart rate.

Take your RHR first thing after waking up in the morning. Feel your pulse at either your carotid (neck) or radial (wrist) artery for one minute over several days to obtain an average RHR. In general, the more efficient your heart, the lower your RHR will be. (Note: As you grow older, your RHR will generally increase slightly.)

The next step is to determine your maximum heart rate (MHR). Most physiologists believe that 226 beats/minute (female) and 220 beats/minute (male) are the closest approximations of MHR (before age adjustment). To calculate your age-adjusted MHR, take either 226 (females) or 220 (males) and subtract your age. This will give you a reasonably good idea of your MHR on land.

For swimmers, though, the MHR is usually an additional 10 to 13 beats per minute lower, mainly due to four factors:

1) Water allows our bodies to cool faster (water is cooler than our skin temperature);

2) In water, because we are in a non-weight bearing environment, less effort is required to train;

3) We are situated in a horizontal position, which allows our heart to work more effectively;

4) We are using our smaller upper body muscle groups more as opposed to "land" aerobic sports that primarily use the larger, lower body muscle groups.

Using this age-adjusted method for a male, age 30, the MHR would be calculated as: 220 - 30 = 190 - 10 = 180 beats/minute MHR.

Although this method of determining MHR is generally accurate, the most accurate method for finding your MHR is by taking a stress test. Unfortunately, this may cost anywhere from $100 to $500. A more economical way, as Sally Edwards suggests in her book, is after warming up, swim 50 yards aggressively (about 80% effort) using your favorite stroke. Rest two minutes. Using the time from your first 50 yards, add ten seconds to get your starting pace. Next, begin swimming a few 50s at this calculated pace. On each 50, try to decrease the lap time by about five seconds until you can no longer increase the speed. Stop for a few seconds after each 50 and check your heart rate monitor. Your highest value during the test is equal to your MHR.

Once you know your RHR and your MHR, you are ready to train more scientifically with your HRM. By using the monitor and making some small calculations, you can begin to gain a better understanding of how to train more effectively and efficiently. Now you are ready to calculate your five different training levels by using your own MHR. Those levels are:

Moderate to Easy swimming: 50% to 60% of your MHR
Weight Management swimming: 60% to 70% of Your MHR
General Aerobic swimming: 70% to 80% of your MHR
High Aerobic Threshold swimming: 80% to 90% of your MHR
Anaerobic or Red-Line swimming: over 90% of your MHR

In a future article, I discuss the different training levels, the purpose of each level, and a step- wise approach to training by using your HRM. This information can help anyone from lap swimmer to world champion to understand and use the HRM for better physical fitness. It can give you a scientific edge to help you fashion a training program that will be specific for you and your coach.