How many calories can you burn swimming? Cardio, strength, and weight loss benefits

The number of calories you burn swimming depends on factors like time and intensity. For example, the longer and harder you swim, the more calories you burn.

If you’re not a triathlete or competitive swimmer, swimming laps may not be the first thing that comes to mind when you think of cardio. But jumping into a pool is definitely a worthwhile workout to mix up your routine. In fact, pulling yourself through the water can strengthen your entire body—and the calories burned swimming quickly add up.

‘Although swimming sometimes seems relatively hard and scary, it’s one of the best cardiovascular workouts anyone of any age can do,’ says Kris Gagne, a registered and certified swim coach with USA Swimming and the American Swimming Coaches Association. As you continually use just about every muscle to move your bod from one end of the pool to the other, ‘the aerobic work helps strengthen the heart muscle itself, making it more efficient at pumping blood throughout your body,’ he explains.

What’s more, swimming, which puts pretty much no pressure on your bones and joints, is a low-impact way to burn calories. ‘The water supports 90 percent of your body,’ Gagne explains.

Of course, just how many benefits you reap from taking your workouts into the water depends on a few key factors. Here’s what to know about how many calories you can burn swimming⁠.

Meet the expert: Kris Gagne is a registered and certified swim coach with USA Swimming and the American Swimming Coaches Association.

Benefits of swimming workouts

If you’re not sold on the idea of donning a pair of goggles, allow me to remind you of all of swimming’s pretty spectacular benefits.

1. It’s a great cardio exercise that helps prevent heart disease.

I said it once and I’ll say it again: Swimming is a great form of cardio, since you’re challenging your heart and lungs to pump oxygen-containing blood throughout your system to keep you moving. You’re basically always going to be out of breath after a good session.

In the long run, a swimming habit makes a major difference: ‘Studies with the American Heart Association have found that just 30 minutes of swimming a day can reduce coronary heart disease in women by 30 to 40 percent,’ says Gagne. Impressed.

2. Swimming tones your muscles and builds strength.

Because you have to overcome the resistance of the water when you swim, every stroke you take helps to build strength in your muscles, says Gagne. Specifically, moving your body through the water requires all of your major muscle groups—from your arms to your legs to your core—to get working, Gagne says.

3. You can get variety within your swimming workouts.

By incorporating different swimming strokes—like breaststroke, backstroke, butterfly, sidestroke, and freestyle—you can work all of your muscles in different ways within a single workout, Gagne adds.

How many calories do you burn swimming?

While swimming is generally a pretty darn impressive calorie-burner, just how many you torch depends on several factors, including your weight, intensity, and which stroke you’re doing.

Generally, Harvard Medical School estimates that in 30 minutes of recreational swimming:

• a 125-pound [57kg] woman will burn about 180 calories
• a 155-pound [70kg] woman will burn about 216 calories
• and a 185-pound [83kg] woman will burn about 252 calories

However, if you turn up the heat and vigorously swim laps for 30 minutes, your calorie-burn increases. In this case,

• a 125-pound [57kg] woman will burn about 300 calories
• a 155-pound [70kg] woman will burn about 372 calories
• and a 185-pound [83kg] woman will burn about 444 calories

The stroke you select also has a major impact on how many calories you torch. While a 155-pound [70kg] woman burns about 372 calories in 30 minutes of swimming breaststroke, for example, she’ll burn closer to 409 calories in 30 minutes of butterfly.

Do you burn more calories swimming than you do running or biking?

Fun fact for all of you swim skeptics out there: You can totally burn as many (if not more) calories in the pool than you can on the bike or tread, as long as you put in the effort.

If you run at a 10-minute mile pace, for example, you burn about as many calories in 30 minutes on the tread or pavement as you would in the pool, per Harvard Medical School. However, if your pace lands closer to 11-plus minutes per mile, you’ll burn more calories in the pool.

It’s a similar story when it comes to swimming and cycling. Spin those wheels at a moderate pace for 30 minutes on the stationary bike, and a 155-pound [70kg] woman burns about 260 calories. (That’s almost 100 fewer calories than 30 minutes of vigorous laps.) Kick up the spinning intensity to an all-out effort, though, and that same woman burns about 391 calories in 30 minutes, rivalling 30 minutes of butterfly in the pool (409 calories).

What affects how many calories you burn while swimming?

The four biggest factors that influence how many calories you burn in the pool are: your body weight, what swimming stroke you use, how hard you work (intensity), and how long you swim for (duration).

Of course, intensity and duration are pretty obvious. The longer and harder you swim for, the more calories you burn, Gagne says.

Prefer to keep your workouts on land? Try this 20-minute full-body sesh:

Body weight then factors in because the more weight you have, the more effort you’ll have to expend to move yourself through the water. Plus, a larger body size means you have more surface area in the water, which then means you’ll face greater resistance and need to work harder to continue moving.

Then comes the stroke you pick. Certain strokes are more technical and expend more energy than others, explains Gagne. Since butterfly involves sweeping both arms up out of the water and straight out in front of you at once (while performing a difficult dolphin kick), it’s much more exhausting than breaststroke, in which you can more leisurely frog kick and pull yourself through the water.

How to burn more calories swimming

Lucky for you, you don’t have to do lap after lap of butterfly (it’s hard!) to burn calories while swimming. Incorporate these three strategies the next time you dive in.

1. Create more resistance

‘The more resistance you have in the water—whether using equipment or your own body—the more calories you’ll burn,’ says Gagne. Steal a move from swimming pros and layer a slightly-loose swimsuit over your go-to Speedo (this is called a drag suit) or try out gear like hand paddles or fins.

2. Incorporate intervals

You know upping your swimming speed means more calories burned, but you don’t have to sprint for 30 minutes straight to see big benefits.

Whether you’re crunched for time or building up your stamina, Gagne suggests using interval training. For instance, swim as hard as you can for 30 seconds, then swim at a leisurely pace for 60 seconds, then repeat.

Just like HIIT on the tread, breaking up your pool workout this way allows you to maximise your effort and time while improving your performance and burning calories.

3. Swim IMs

In an IM (a.k.a. individual medley), you swim each of the four primary strokes back-to-back to switch up the stimulus on your bod and, ultimately, turn up your burn, suggests Gagne.

Try this: Swim one lap of butterfly, then a lap of backstroke, then a lap of breaststroke, and finally a lap of freestyle. Use the strokes that feel easiest to you as recovery, or do a few laps of leisurely breaststroke or backstroke after your IM to recover before repeating.