Friendship and fitness! How do celebrities like Reese Witherspoon, Cameron Diaz, and Nicole Richie stay in shape? By assuming downward dogs, hitting the pavement, and shedding those pounds -- together! Click through to see more stars and their workout buddies.
Heidi Klum and Brooklyn Decker
Brooklyn runs the Bridge! Fellow models Decker and Klum ran across the famed Brooklyn Bridge together back in 2011, looking amazing and athletic.