07/13/2011 05:14 pm ET Updated Sep 12, 2011

Why Your Mom Was Right About Slouching

Your mom always told you to stop slouching, and now science is on her side.

A new study in the Journal of Experimental Social Psychology shows that having a "dominant" posture, versus a submissive one, decreases sensitivity to pain.

That's likely because people feel more powerful and in control when they are standing up straight, said researchers from business schools at the University of Southern California and the University of Toronto.

In the study, 89 people were told to either maintain a dominant stance, consisting of sitting or standing up straight and puffing out their chests, or a submissive stance, consisting of slouching with their arms and legs crossed, LiveScience reported.

Blood pressure cuffs were then put on the study participants, who were told to say "stop" when it became painful or uncomfortable. The people who had the dominant stances were able withstand more pain than people with the submissive stances, according to LiveScience.

"A dominant posture can trick the brain into feeling in control," study researcher Vanessa Bohns, Ph.D., a post-doctoral fellow at the University of Toronto, told Men's Health. "But a submissive posture can activate stress reactions that can make the pain worse."

The finding adds to previous research that shows that having a dominant posture increases the production of testosterone and decreases levels of the stress hormone cortisol, the Daily Mail reported.

But sitting up straight can do more than help with the way you deal with pain -- it also reduces back pain and fatigue. Research also shows that people who sit with their heads jutted out have worse headaches than people who sit properly.