Confession: I hate stretching, and I haven’t been able to touch my toes in years. For a while, I shrugged off my lack of flexibility as a minor problem in the grand scheme of my overall fitness.

If you've been waking up stiff, struggling with achy joints or feeling like your body just doesn't move the way it used to, you're not alone. But here's the feel-good news: A new study reveals that ...