Uphill running forces you to drive your arms harder than you do when running on flatground, 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 flatground).
This is, of course, assuming they don't suffocate, say, if you dropped them from 40,000 feet, and that they land on relatively flatground (nothing pointy or the like).