When you use your muscles beyond what they can handle, either through aerobic exercise or weight bearing exercise, it causes your body to build new muscle tissue.

当你用你的肌肉做些有难度的活动时，不论是有氧运动还是负重运动，都会让你的身体建立新的肌肉组织。

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Your self-control "muscle" is just like the other muscles in your body — when it doesn't get much exercise, it becomes weaker over time.

你的自我控制“肌肉”就像你身体的其他肌肉一样——当它没有得到大量锻炼的时候，它会随着时间变弱。

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Yet another great way of relaxing is an exercise where you tense each muscle in your body, one body part at a time, and then let the tensed muscle relax.

另一个很妙的放松方法就是锻炼。锻炼能拉紧你的每块肌肉，每次锻炼身体的一部分，然后让紧绷的肌肉放松。

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Not only are you healthier as a result, your comprehensive exercise program, which includes cardiovascular and weight-bearing exercise, is preventing further weight gain and allowing you to maintain muscle mass so your metabolism does not drop significantly as you get older.

CNN: I'm exercising; why can't I lose weight?

Before I answer your question, let me clarify that while metabolism does drop with age (about 3 percent per decade) due to muscle loss and hormonal changes, it does not drop with exercise, but rather increases due to direct calorie burning during your workouts and indirectly through an increase in muscle mass as a result of your workouts.

CNN: What's the best way to 'kick-start' my metabolism?