Dick Van Dyke still tries to "hit the gym three times a week," even as he nears 100 years old. "I'm not a 'wake up and go back to bed' type just yet, unless it's cold and rainy," Van Dyke wrote in his book 100 Rules for Living to 100: An Optimist's Guide to a Happy Life, published on Tuesday, November 18. "If I miss too many gym days, I really can feel it - a stiffness creeping in here and there in my joints." Van Dyke wrote that he has to "dangle" a few "carrots" in front of himself when feeling "sluggish and reluctant" on a gym day.