Not taking the elevator is a good way to sneak in a little extra exercise every day. And if you do get some of your exercise avoiding elevators, here's a burning question: do you burn more calories climbing stairs one at a time or bounding up them two at a time? To find out, researchers had subjects climb stairs reaching 46 feet high. Based on the subjects' heart rate measurements, the researchers estimated calories burned. They found that volunteers who took the stairs two at a time had a higher rate of energy expenditure over the 86 steps they climbed—but those who climbed one at a time burned more energy in total over the entire staircase. The study is in the journal PLOS One. It makes sense. Although the bounders had a more intense workout, the one-steppers take longer to get to the top. So even though they're burning fewer calories per minute than the bounders do, they work out enough longer to burn more total calories. And one step or two, there's never a wait for the stairs.