The central theme is it just shouldn't be a mystery why, if you gain weight, you get metabolic disease.

核心主题不应该是一个谜，如果你体重增加，你就会出现代谢性疾病。

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If you're carrying twins or triplets, you might need to gain more weight.

如果你打算怀双胞胎或者三胞胎你要增加更多的重量。

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If you want to lose weight or gain muscle, you need to train hard for weeks on end to see results.

如果你希望减轻体重或者增长肌肉，你需要去刻苦地训练几周然后才能看到结果。

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If you eat more calories than you burn, usually you will gain weight as the body stores the excess.

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If you gain fat easily, stay on the lower end of the range, and if you find it very difficult to gain weight in general, aim for the higher end of the range.

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And if you eat and drink more calories than you burn off, you'll gain weight.

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