The exercise habit keeps our weight in check, our moods in check and the ups and downs of life easier to manage.

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"Like Rodgers and Hammerstein, I'm not afraid to deal with themes about the ups and downs of life, yet which are still entertaining, and you still feel these stories, " he says.

BBC: Harvey Weinstein stages Finding Neverland in Leicester

Resilience is not just about moving on from mistakes as they happen, but staying on track despite the inevitable ups and downs of work and life.

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Capital markets are imperfect, they observe, and households are unable to insure themselves against all of life's ups and downs.

ECONOMIST: Free exchange