Is Running Outside Harder than Treadmill Running?
Reader Tara is doing the Run Your First 5K program and just tried running outdoors, after a few weeks on the treadmill. She writes: "I found it very hard to run outside, and got intense cramps in my lower side! Is that normal?"
...Source: http://running.about.com/b/2011/06/02/is-running-outside-harder-than-treadmill-running.htm
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