The Surprising Benefits of Having Fun at Work Since you have to be there all day anyway, make enjoying it one of the things you get done daily.

Today we celebrate National Fun at Work Day. This unofficial holiday is known by some to always be celebrated on January 28, but some prefer to celebrate it on the last Friday in January.

And who doesn't love to have fun? However, if you ask an adult, "What do you want to do today?" what are the chances that you'll get the response: "Let's play!"? Maybe that's why so many people in our society are so stressed, uptight and unhappy. Most of us have lost our spontaneity.

Physician and author Oliver Wendell Holmes once said, "We don't quit playing because we grow older; we grow older because we quit playing." I agree. In the workplace, play is a tool smart entrepreneurs use to bring out the best in people and strengthen relationships between employees.

Here are some ways you can incorporate play into your workplace and have fun all throughout the year.

Have fun with photos.

Set up a studio in an empty office, hallway, or conference room. Hire a photographer or use the best photographer on staff to take group and individual shots. Then post them to your company Facebook page, Instagram or your company blog or website.

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Get physical.

Establish a series of contests for staff members trying to get in shape. Set up an hour-long health conference to establish guidelines and share a healthy lunch. Participants can then track key metrics —number of steps taken, floors climbed, distance traveled, calories burned -- on their wearable devices. The group can meet weekly or monthly to share their data, fitness tips, and healthy recipes.

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Organize games and activities.

Companies including Dropbox offer recreational equipment including ping-pong tables and a music studio as perks, while Eventbrite takes its employees on team outings to the trampoline park. Keller Williams uses a cornhole (beanbag toss) game to determine who gets to use the single dedicated parking space each month, and Google offers volleyball courts, a heated swimming pool and an indoor slide at its company headquarters. You don't have to be a big corporation to have fun. Organize softball, tennis, soccer, or bowling tournaments and other team challenges.

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Bring comedy into the office.

A U.K. study of 700 participants by the Social Market Foundation and the University of Warwick's Centre for Competitive Advantage in the Global Economy showed that productivity increased by an average of 12 percent and as high as 20 percent after viewing a comedy clip and enjoying snacks and drinks. Dr. Daniel Sgroi, the report's author suggests showing a short film or some crazy commercials. Incorporate humorous videos into your PowerPoint presentations. Everyone will leave with a smile on their faces.

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Break out the tunes.

Bring in your own soundtrack or use one of the online music streaming services like Spotify, Pandora or iHeartRadio to set a fun tone around the office during dedicated "happy" hours (no alcoholic beverages necessary).

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Eat, drink and be merry.

Take off early one day and invite your coworkers out to a local restaurant or bar for happy hour. There's no reason you can't take the happy outside of the office. Authors Dave Hemseth and Leslie Yerkes of 301 Ways to Have Fun at Work state that, "Organizations that integrate fun into work have lower levels of absenteeism, greater job satisfaction, increased productivity and less downtime."

Having fun at work is proven to have substantial effects on workplace productivity. Use your imagination and make play a common and useful occurrence in your workplace.