Gray Rollins is a featured writer for TheRunnersGuide.com. For more tips on staying motivated to run and for a marathon training guide, please visit the site.

• 音乐也可以很鼓舞.；如果你有困难的时候；如果你还是专注在你有选择不办；因为你觉得太无聊；随着你尝试引进一些音乐