Best and Worst Health Trends of 2013

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Best: Fun runs

Whether it involves running through foam-covered obstacles or getting splattered with colored powder, fun runs have it right: Fun is the ultimate motivator, according to Edward L. Deci, PhD, a motivational researcher and professor of psychology at the University of Rochester. People who work out for the pure joy of working out rather than for a result (think: lose those last five pounds) actually stick with workouts longer and reap better results, he says. So grab your girlfriends and sign up!

Next: Best: Going vegan