You do the exact same training program as your running partner—but finish the 5K 10 minutes behind her. After months of diligent forward bends, you still can’t even touch your toes. And while your totally toned co-worker swears by a strength-building DVD, you don’t see a single sculpted muscle for your efforts. Before you blame yourself or give up altogether, consider whether your obstacles have been written into your genome. Read the full article on Prevention.com.