How can you tell if you're burning calories?

I always thought that if you were doing some exercise (i.e. running) that got your heart rate up and made you out of breath, you were burning calories. Is there a different way to tell?
Answer:
Burning calories smell like bacon.

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You're always burning calories! Exercise helps you burn them faster!

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Buy some keto-sticks. They let you know if you're burning fat or not.

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Any exersize burns calories
even sleeping burns them.

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If you are alive, you are burning calories.

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