Depending on how much effort you put into it and how much you weigh, swimming breaststroke for an hour will burn between 600 and 888 calories, according to Harvard Health Publishing.
How Breaststroke Stacks Up
Swimming breaststroke can burn roughly as many calories as taking a run, according to Harvard Health Publishing. A 125-pound person would burn about 600 calories while doing the breaststroke or running 6 miles per hour — equaling a pace of running a 10-minute mile. The breaststroke calories burnt jump to 744 for a 155-pound human and 888 for both activities for a person weighing 185 pounds.
Running at a faster pace, however, will burn more calories than swimming the breaststroke. Stepping it up on land to just 7.5 miles per hour will burn 750 calories for a 125-pound person or 1,110 calories per hour for a 185-pounder. If you can crank out a 10 mile per hour pace — running a mile in six minutes — you'll burn 990 to 1,466 calories.
But there are far less productive things you could be doing than counting your breaststroke calories burnt. Swimming backstroke, for example, delivers a calorie burn of only 480 calories per hour for a 125-pound person, the same as playing beach volleyball, snowshoeing, cross-country skiing or marathon wheelchair racing. Walking at 4.5 miles per hour burns 270 calories per hour, the same as leisurely swimming in general.
Increase the Burn
Although breaststroke sears through an average of 734 calories per hour for swimmers, according to the Just Swim Calorie Crunch Calculator at Swimming.org, there are a few ways to expend even more. The speed at which you swim, the distance you swim and your respiratory exchange rate — the ratio of your body's carbon dioxide production to its oxygen consumption — all affect how many calories your body consumes, according to Swimming Science.
Use a calories burned swimming calculator that takes all three factors into account to up your caloric consumption. For example, if you swim breaststroke at 0.59 meters per second — about 1.31 miles per hour — at a slow pace with a respiratory exchange ratio of 0.7, you'd burn about 9.6 calories for every 50-meter repetition according to Nanyang Technological University's calories burned swimming calculator.
Increase your pace and increase the burn. A respiratory exchange ratio of 1.0 associated with an intense pace ups the 50-meter calorie burn to 15.25 calories if you double your pace to swim at a rate of 1 meter per second or 2.2 miles per hour.
- Harvard Health Publishing: "Calories Burned in 30 Minutes for People of Three Different Weights"
- Swimming.org: "Calorie Crunch Calculator"
- American Council on Exercise: "Tools and Calculators"
- Nanyang Technological University: "Energy Expenditure in Swimming"
- Swimming Science: "How to Calculate How Many Calories You Burn When Swimming"
- Metric Conversions: "Meters Per Second to Miles Per Hour"
- ScienceDirect: "Respiratory Quotient"