Speaker 1: Welcome to brain Stuff from how stuff works dot com
Speaker 1: where smart Happens. Hi, I'm Marshall Brain. Have you ever
Speaker 1: been to the gym and used a piece of equipment
Speaker 1: that tells you the number of calories that you've burned?
Speaker 1: The New York Times ran a story this week explaining
Speaker 1: how bad these calorie estimates really are. Intuitively, we know
Speaker 1: that these estimates are often wrong. Here's how we know that.
Speaker 1: It's easy to jump on a ster machine and have
Speaker 1: it tell you that you've burned a thousand calories in
Speaker 1: half an hour. But here is the comparison you have
Speaker 1: to keep in mind. Imagine that you go out running
Speaker 1: and you run ten miles in one hour. That is
Speaker 1: ten six minute miles. Most people couldn't even do it.
Speaker 1: If you could do it, imagine how you would feel
Speaker 1: that ten mile run is, roughly speaking, when thousand calories burned.
Speaker 1: You would have to feel that bad to burn a
Speaker 1: thousand calories. And even that is a rough estimate because
Speaker 1: it changes wildly depending on how much you weigh, how
Speaker 1: old you are, and things like that. So you have
Speaker 1: three things that are corrupting the meters on most exercise equipment. First,
Speaker 1: people vary wildly in size, shape, and condition. Second, people
Speaker 1: can do things that make exercise easier. For example, they
Speaker 1: can hold onto the rails on a ste machine and
Speaker 1: cut the number of calories burned in half. Third, manufacturers
Speaker 1: seem to be overly optimistic because it makes their customers
Speaker 1: feel good. Add this all together and you can get
Speaker 1: some really bad calorie estimates. Be sure to check out
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Speaker 1: Stuff Work staff as we explore the most promising and
Speaker 1: perplexing possibilities of tomorrow the house Stuff Works. I Find
Speaker 1: app has a arry down at it today on iTunes