Oh, form, how you slay us all.
Fiance will tell you that I regularly comment on poor running form. For at least a year he's been trying to get me to get certified as a track and field coach legit style. Its hard for me, when I see women hunched over (your boobs are not supported for the love of God) or men running with their arms swinging from straight to bent (you are going to pop one of those elbows). But running form can mean the difference between an efficient workout and one that tears ligaments.
Friends who regularly attend my spinning class openly call me the posture Nazi. They are not kidding. I probably cue posture more than I scream the word sprint. Head up, long back, arms straight but not locked out...the list goes on.
I know, I know, lay off every one's case, they're doing their best. Its true, they probably are. The reason I'm vocal about this isn't because I like to correct people (although I occasionally enjoy correcting people in those idiotic Lance Armstrong outfits at indoor cycling classes). The reason I'm vocal is because I have two bad knees, one worse than the other, a cervical spine that is a total disaster and popping ankles. I even have one toe that is so busted that it pops when I just simply bend it. And yes, I still work out like a fiend. You can too! Because its all in the form. Better form means a more efficient workout means more calories burned means more muscles fatigued (in the safest way) leading to more bacon and cake eating . . . or something.