This is a weekly series on the latest happiness research. Learn and be merry! 

Chief happiness officer – According to the 2013 Global Entrepreneurship Monitor U.S. Report, owners of established businesses are significantly happier than owners of new businesses and non-business owners. Women owners of established businesses are even happier.

Dive in – Regular swimming can increase your positivity by about a third in just a month, reported British Gas SwimBritain. It can also improve sleep, energy, and fitness levels.

Go all the way – According to a study published in Social Psychological and Personality Science, the psychological effects of casual sex may depend on your personality. People who are “sociosexually unrestricted,” or have a tendency for casual sex, may feel increased self-esteem and satisfaction and lower depression and anxiety after the experience. People who fit this description tend to be impulsive, extroverted, strong men.

Try, try again – Analysis of the famous Grant Study found that middle-aged people in unhappy marriages are unlikely to turn things around. In these cases, divorce is more likely to lead to happiness.

Photo by Flickr user  Singapore 2010 Youth Olympic Games