When people say, “You can’t outrun a bad diet,” I smile and nod. It’s perfectly true, in a holistic sense. Exercise and diet are two different things, with separate effects on your health and performance. You can’t automatically compensate for deficiencies in one area by being extra good at the other, any more than donating to charity makes it OK to embezzle at work.
Still, there’s a little voice in my head that asks: “Well, how far were you planning to run?” It may be true that you’d have to jog three or four miles to burn the calories in a single McDonald’s Happy Meal, but some people run a lot farther than four miles. The question of how many calories a person can burn in a given day is an interesting scientific one, with some researchers arguing that our ability to get food through the digestive tract is actually the fundamental limitation on feats of sustained human endurance.
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