Personal trainers: Do you recommend that your clients wear heart rate monitors? Why or why not? IDEA asked several trainers for their opinions.John Platero, director of education for the National Council for Certified Personal Trainers, Newbury Park, California, requires each of his clients to purchase a heart rate monitor and wear it when they train together. Here are some reasons why.
“My client and I wear a Polar F series model so I can monitor heart rate without having to take the client’s pulse, grab his wrist or stop him from exercising,” says Platero. “The heart monitor also shows the client his average heart rate, maximum heart rate, calories expended and percentage of those calories that came from fat. This information educates the client as to what activities or positions burn the most calories, the concept of anaerobic threshold (AT), how it feels to train at or above the AT and how to determine rest periods between sets. In addition, the monitor helps me make better choices in program design. I can tell when a client has adapted to a particular mode or intensity and when it's time to change it up. The monitor also presents a clearer picture of the relationship between volume and intensity. As intensity increases, volume will decrease. As the client’s fitness improves, I slowly add back volume while maintaining intensity.”
Mary Miriani, an ACSM health/fitness instructor at Reality Fitness, Naperville, Illinois, recommends that her post-cardiac-rehab clients and diabetic clients use a good heart rate monitor during cardio workouts as a constant reminder of fluctuations in heart rate. “I also tell these clients not to get too attached to the numbers, and I teach them to use RPE (rating of perceived exertion) along with heart rate. It is important in these populations to use both methods, given the higher risk of cardiac events and the effects of medication on heart rate.”
For other clients, Miriani does not rely on monitors as the best means of assessing intensity. “The reason I do not want my clients measuring exercise intensity solely with heart rate monitors (especially ones built into cardio machines) is that they can be inaccurate and improperly used,” she says. “Heart rate monitors often measure pulse rate for 5- to 15-second intervals and correct to the pulse rate for a minute. This method creates a small margin of error. Some people have undiagnosed dysrhythmias, such as premature ventricular contractions, and a monitor will fail to count them and give an inaccurately low number. Some people will then mistakenly increase intensity to stay at the target heart rate with dangerous results. Also, some medications alter heart rate, and I do not want clients to increase intensity inappropriately.”
When Miriani feels heart rate is important to keep track of, she also teaches RPE and common sense. “I tell my clients that even if the monitor is telling them that their heart rate is too low, they should not increase intensity if they feel their exertion is high on the RPE scale. To be at the right intensity, they should be able to say a phrase but not carry on a conversation. I use palpation for 30 seconds rather than relying on a monitor (even if my client is wearing one) during exercise testing. This method has enabled me on at least two occasions to detect possible dysrhythmias. I was able to suggest that my clients see their doctors before a cardiac event could occur. Needless to say, my clients were grateful when their conditions were caught in time.”
For perspectives from other personal trainers, please see “Tricks of the Trade” in the May issue of IDEA Fitness Journal or read the column online in the IDEA Library.