Forget them... run for it!

 The most annoying thing in the world, other than fad diets that do more harm than good, and all the women who refuse to lift sufficient weight because they thing they'll look like a beast overnight, is listening to all the hype about how bad running is. The terrible part about this commotion, is that the people who make these bogus claims are people who have no idea what they're talking about, who make assumptions based on correlating but non-causative events.

Several people tell me about their friend's uncle who had both of his knees replaced because he's been running all of his life. In reality, that uncle had his knees replaced because either A. lack of proper training or B. didn't listen to his body while running or resting like he should have. In Anatomy 301 in college, I wasn't even a runner yet. I didn't yet have that understanding about the wonders running does for you body. If someone even made such a comment with "wonders" and "running" in the same sentence to me, I would have thought they were crazy. However, I will always remember my professor explaining Wolff's Law: "Every change in the function of a bone is followed by certain definite changes in its internal architecture and and its external conformation." In Lehman's terms, Wolff's Law explains that a bone strengthens and deposits mass in response to the stress placed upon it. Running, with proper form, is actually great for you. It builds your bone mass better than any other aerobic activity. I say better only because you can withstand running for a longer period of time than plyometrics or other high intensity activities. For proper running form, check out Chi Running by Danny Dreyer. Pretty awesome stuff. I have not suffered any major injuries since I started following his Chi Running guidelines, and I actually run much faster and more efficiently.

Check out this article posted on Runner's World. Maybe you'll be inspired to go for a run :) 
10 Reasons Why Running is GOOD for You

I also get chastised by cyclists for running so much. They argue that running is hard on the body whereas cycling is so much more gentle and efficient. Again, I cite to them Wolff's Law. On a bike, you have no weight bearing pounding to signal your body to increase your bone density. Thus, over time you can actually decrease your bone mass by cycling and not doing any type of running or weight lifting exercises, due to the simple fact that bone mass decreases as you age naturally. Check out this article which explains my understanding.
Why Running is Better than Cycling