The Target Heart Rate for Swimmers

Swimming is an excellent cardiovascular exercise, particularly if you swim intensely enough to achieve your target heart rate. Exercising below your target heart rate has no effect on your heart or lungs, according to the textbook “An Invitation to Health” by Dianne Hales. Your target heart rate during exercise depends on your age. Most exercises require the same target heart rate, but swimming requires a lower target heart rate as the heart beats slower in water.

Exercise experts differ on what your target heart rate during exercise should be. The Merck Manual Home Health Handbook and “An Invitation to Health” recommend that it be 60 to 85 percent of your maximum heart rate -- 220 heartbeats per minute minus your age. Exercise expert Kenneth Cooper recommends a target heart rate of 65 to 80 percent of your maximum heart rate. The University of Maryland Medical Center and Chicago’s Rush University Medical Center recommend a target heart rate of 50 to 75 percent of your maximum heart rate. Exercising at or near your maximum heart rate is risky, says Hales.

Your target heart rate during exercise decreases as you get older. Hales determined target heart rates necessary to raise your heart rate to 60 to 85 percent of your maximum heart rate while you’re exercising. If you’re 20 years old, your target heart rate would be 120 to 170 heartbeats per minute. Your target heart rate in heartbeats per minute would decline to 114 to 162 at age 30, 108 to 153 at age 40, 102 to 145 at age 50, 96 to 136 at age 60, and 90 to 128 at age 70.

Your heart beats slower in water than on land because your lower body temperature in water slows your metabolism. Swimming slows your heart rate even more because the water supports your weight and your heart delivers oxygen to your body with less effort when your body is horizontal, according to “The Complete Guide to Walking for Health, Weight Loss and Fitness.” The University of Maryland Medical Center reports that swimmers’ target heart rates should be 12 beats per minute fewer than people who exercise on land. Your target heart rate in heartbeats per minute should be 108 to 158 if you’re a 20-year-old swimmer, 102 to 150 at age 30, 96 to 141 at age 40, 90 to 133 at age 50, 84 to 124 at age 60, and 78 to 116 at age 70.

The Merck Manual Home Health Handbook notes that swimming works the entire body without putting stress on joints and muscles. It is also promotes weight loss, muscle function and flexibility. Cooper wrote that swimming is a particularly good exercise for people who have arthritis or musculoskeletal problems. He recommends that beginners swim 300 yards daily four times per week.