Do you jump right into a workout without warming up? Do you “jerk” the weights when strength training? Do you overstretch in Yoga class because you don’t want to look like a noob? Editors from Fitness Magazine offer some tips in this article, but I’d like to go past the obvious and get to the real story about poor fitness habits. The worst habit of all is working out purely for cosmetic reasons. You know what I mean: pumping weights just to look good instead of developing core strength. Or hanging out in yoga class just to show off how limber your pelvis is.