每克蛋白质是4卡路里，所以这位54.5千克、每天需要大约54克蛋白质的跑步者每天有200到220千卡的能量来自蛋白质。

One gram of protein equals 4 calories, so our 120-pound runner, who needs approximately 54 grams of protein, should allow 200 to 220 calories for protein each day.

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就营养学而言，食物中的热量通常以千卡计，但简称为卡路里。

In terms of nutrition, values are often given for the number of kilocalories in a food but referred to simply as calories.

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