Uphill running forces you to drive your arms harder than you do when running on flat ground, so you'll improve your upper body strength.

使您的上身有劲：跑坡道迫使您摆臂比跑平地时更加用力，因此，您的上身力量可以提高。

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Hills. If you run or bike or walk for cardio, you'll want to incorporate hills (after the first month or two of doing it at an easy pace on flat ground).

如果你通过跑步，骑车或者走路来锻炼心脏，那么结合斜坡，效果更好(通常在平地上锻炼一两个月以后进行。)

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Although its nesting habits are similar to those of gulls that nest on flat ground there are a number of important differences related to the cliff - nesting habit.

虽然它的筑巢习惯和那些在平地筑巢的海鸥很相似，但悬崖的筑巢习惯还有很多重要的不同。

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People driving during a tornado are told to find low ground and lay flat,facedown, with their hands covering their head.

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It sits flat on the ground with the bottom open to the earth.

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Men lay flat on the ground. They prayed for the shelling to stop.

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He resumed throwing Feb. 25 from flat ground and completed a long toss session from 130 feet on Thursday.

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The trip through the cities of Illinois, the flat ground of Indiana, and the northern part of Ohio was uneventful.

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We didn't clock our speeds, but the bike can supposedly top about 15 miles per hour on flat ground with the pedal-assist on, and that sounds about right to us.

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