How many calories are burned swimming an hour of breakstroke?

The answer to this question depends on how much you weigh and how hard you stroke ;-). The more you weigh, the more mass you have to pull through the water and the more calories you burn/min. Obviously the harder you work, the more calories you burn. There are lots of places on the web where you can get the answer to this question.

For example 1 150 pound person swimming breaststroke for 60 minutes, burns 714 calories.