“We tend to think," says Marc Schulz, "that once we establish friendships and intimate relationships, they will take care of themselves. But like muscles, neglected relationships atrophy.” Today, Marc shares the fitness regimen to keep your relationships fit and trim.

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• Marc is a professor of psychology at Bryn Mawr College and the associate director of the Harvard Study of Adult Development. He’ll be with us all week to discuss his new book, “The Good Life: Lessons from the World's Longest Scientific Study of Happiness.”

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