How to do it: lie flat on your back with one arm outstretched perpendicular to your body.

如何做：仰面平躺，单臂平伸并与身体垂直。

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Rotational stretch. Lie flat on your back. Bring one leg up to a 90-degree angle and hold.

转动伸展。背部着地平躺，一条腿向上升呈90度，保持住。

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How it works: Lie flat on your back. Hold the book above your head and read until your arms are sore.

怎么做：平躺下，仰卧。把书举到头部上方看，直到胳膊酸痛。

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"Sometimes you see the world more clearly when you're flat on your back, " NBC Universal Chief Jeff Zucker admitted earlier this year.

FORBES: Magazine Article

Lying flat on your back, for instance, may be good for the lower back but can exacerbate digestive and breathing problems and snoring.

WSJ: Find the Perfect Sleep Position

Lie flat on your back on a blanket, lawn chair or sleeping bag and look up, taking in as much of the sky as possible.

MSN: How to see the supermoon �� and shooting stars, too