Written by Linda Melone, ACSM Certified Personal TrainerSM
Back in the days of leg warmers and high-impact aerobics, instructors posted colorful heart rate charts for participants to monitor their exercise exertion. Bright columns of green, red and yellow “zones” indicated whether you were in the aerobic zone, the fat-burning zone or the (heaven forbid!) anaerobic zone. In more recent times, monitoring heart rate remains a hotly debated issue: How important is it to track your heart rate and how can doing so help you reach your fitness goals?
Have a Heart
First, know that maintaining a healthy heart is one of the most important reasons to exercise. And, since the heart is a muscle, regular exercise increases the heart’s capacity to deal with new tasks without strain — much like strengthening skeletal muscles. Your heart rate gives you a play-by-play account of your body’s responses to changes in your physical activity. It also determines whether you’re working hard enough to get the results you desire or if you’re not allowing enough recovery time after your last workout (your resting heart rate will be higher than normal).
In order to find the best “zone” for your goals and activity, you must first know how to calculate your maximum heart rate. The following formula offers a rough baseline: 220 – Age = maximum heart rate (MHR)
Pick a Number
For endurance training and general aerobic conditioning, calculate 50 to 65 percent of your maximum heart rate if you’re a beginner; 60 to 75 percent for intermediate level exercisers; and 70 to 85 percent for established aerobic exercisers. For example, if you’re a 45-year-old beginner with no known health issues, your maximum heart rate is approximately 175 beats a minute. Fifty to 65 percent of that maximum is 87 to 113 beats per minute; this is your starting point for cardiovascular activity.
For weight loss, use interval training to burn the most calories. Short bursts of high-intensity exercise (80 to 85 percent of your maximum heart rate) followed by lower-intensity recovery periods (50 to 65 percent of your maximum heart rate) burns more calories than exercising at a consistent level of exertion for the same amount of time. Richard Cotton, M.A., ACSM’s National Director of Certification Programs, cautions, “Speed or anaerobic training done above those ranges (85 percent and over) and is not recommended for beginners.”
Your heart rate can also help you keep tabs on your progress: measure your heart rate 15 to 60 minutes after exercising and compare these numbers over time as you get in better shape. The numbers decrease as your heart becomes stronger.
Heart Rate Monitors
Far superior to manually taking your pulse, a wireless heart rate monitor tells you your heart rate within seconds. However, not all coaches and trainers like to rely on them. Danny Stein, President of the South Coast Roadrunners, says he rarely uses heart rate monitors but instead coaches his runners to develop a “feel” for pace and threshold. Stein says, “I use heart rate monitors with beginning runners, mostly, because they tend to overdo it on recovery days. Using a monitor teaches them to know where they should be.”
Keeping track of your heart rate during exercise assures that you get the most bang for your exercise buck.
View the full winter 2009 issue of the ACSM Fit Society® Page online.