Temperatures are rising, and for people who exercise outside, that might mean it’s time to switch from jogging on blacktop pavement and, instead, opt to do their cardio at the local pool. Don’t be fooled just because you can’t feel the sweat you work up when you’re submerged in cool water. A good lap session has the potential to torch calories, work your muscles, and potentially rival the quality of the workout you get from running.
The Centers for Disease Control and Prevention classifies both running and swimming as vigorous physical activities, meaning that your heart rate increases significantly when you do them. If you’re pushing yourself the way you should, you’ll be breathing too hard and too fast to have a conversation. This kind of vigorous exercise is the kind the U.S. Department of Health and Human Services recommends you do for at least 75 minutes per week (or you could do 150 minutes weekly of moderate activity like walking, playing tennis, or going for a leisurely bike ride).
When it comes to calorie burning, running does have a slight edge: A 154-pound person can expect to burn about 590 calories when running at a pace of five miles per hour, or they can burn 510 calories when swimming slow freestyle laps. Harvard Medical Center states that swimming a certain distance burns as many calories as running four times that distance; in other words, if you swim 1 mile (33 laps in a 25-yard pool), you’ll burn the same number of calories as you would if you ran 4 miles.
And according to a 2018 review published in the journal Sports Medicine, which looked at 29 studies on swimming and running as exercise options, swimming increases VO2 max—that is, the amount of oxygen the body can use during exercise, considered a measure of a person’s aerobic endurance—and reduces body fat just as much as running or cycling.
Swimming even has a few benefits that running doesn’t have. The U.S. Public Health Service Commissioned Corps recommends swimming as a way of staying in shape because it’s a full-body workout, meaning it works every muscle in the body. As your arms and legs work against the density of the water, you build strength and tone your muscles.
While weight-bearing exercises like running are great for developing strong bones, the buoyancy of water make swimming an easy workout for individuals who can’t bear weight, such as those with arthritis, those recovering from injury, or those who are overweight. According to the Cleveland Clinic, this is one of the reasons swimming sees far fewer injuries than running.
Finally, don’t think that the benefits of swimming are limited to doing intensely paced laps. You can still reap the benefits of water resistance by doing water aerobics, playing water polo, doing water jogging, or simply treading water.
As the American Council on Exercise observes, running can be effective for improving health and losing weight, but it isn’t the only option out there, particularly for the many people who find running to be an uncomfortable form of exercise. If running is uncomfortable—and that includes if the weather is too hot—then other forms of exercise like swimming will still fulfill your need for physical activity. Other options include cycling, rowing, jumping rope, dancing, and hiking.
So, if you’re looking to switch up your workout routine as the summer heat gets more intense, try stashing your running shoes in the back of the closet and busting out the goggles instead. You’ll get just as many cardiovascular benefits with less of the sweat.