4 ms·

I'm neither a doctor nor an athlete, but these things cannot be good for your body.

• Locke1689 17y ago
  I wouldn't worry about it -- the human body is made for long distance running. As long as you keep your limits in mind I'm sure it's fine. That said, I've never really tried running more than 10 miles.
• fxdgear 17y ago
  They are perfectly fine. Sure the body takes a pounding, but it also recovers. The most importantthing to remember is that you have to keep your body chemistry as "normal" as possible. Ie, eat foods, drink water, replace electrolytes. All that will help maintain body mass and will keep you from getting pulled.