New research suggests shared pain makes people stronger as a group.

A recent study showed despite its unpleasantness pain can have positive social consequences and act as "social glue," the Association for Psychological Science reported.

"Our findings show that pain is a particularly powerful ingredient in producing bonding and cooperation between those who share painful experiences," said psychological scientist and lead researcher Brock Bastian of the University of New South Wales in Australia. "The findings shed light on why camaraderie may develop between soldiers or others who share difficult and painful experiences."

The researchers randomly assigned 54 students to perform either a painful or painless task in small groups. The students were asked to retrieve metal balls from a bucket and place them in a small underwater container; for some the water was painfully cold while for others it was room temperature.

In a second task the participants were asked to either perform a painful upright wall squat or to balance on one leg with the option of switching legs or using balance aids.

After the experiment the students were asked to measure their feelings towards their group. The students who performed the painful tasks and those who performed the painless ones showed no difference in positive or negative emotion. Students who performed the painful tasks reported a greater degree of group bonding than those who did not.

In another experiment students were asked to play a game choosing numbers between one and seven. If everyone in the group chose the number seven they would get the highest payoff but if they chose different numbers those who chose the lowest would get the higher payoff. The researchers found the students who had performed painful tasks as a group tended to pick higher numbers than those who had not, indicating more group cooperation.

"This finding puts the 'pain as social glue' hypothesis to a rigorous test, highlighting that people not only feel closer to others, but are willing to risk their own outcomes to benefit the group," Bastian said.

The study could help shed light on a number of social and religious practices around the world involving pain, but could also provide insight into our everyday practices.

"These kinds of painful experiences may be relatively common," notes Bastian. "Our findings therefore may have implications for understanding social processes apparent in settings such as boot camp-style physical training programs, team sports, executive challenges, and other physically challenging experiences shared with others. Sharing a spicy meal with friends may even have positive social consequences!"

The findings were published in a recent edition of the journal Psychological Science.