My wife retweeted the article linked below the quite awhile back and thought I’d share. This is something I’ve always found to be personally true with my functioning. Your mileage may vary, but this article definitely speaks to me:
Worker Productivity: Sweet Spot Is 40 Hours a Week

Worker Productivity: Sweet Spot Is 40 Hours a Week http://t.co/ArKudYax
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Worker Productivity: Sweet Spot Is 40 Hours a Week http://t.co/QgW4q6y3
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