If you came into the bathroom one day to find a colleague standing in front of the mirror, hands on hips, shoulders spread wide, doing her best impression of Wonder Woman about to save the world, your first thought would probably be to back out slowly.

But the truth, according to scientists, is that your silly-looking colleague may be on to something not silly at all. Practicing certain "power postures" can actually have outsized effect on mood and confidence and thus on the impression you make on others.

An in-depth post covering research on and advice around body language on the buffer blog recently highlighted a TED talk by Harvard Business School professor Amy Cuddy that explains the biology and impact of body language.

"Cuddy distinguishes between two different types of body postures. One are powerful poses, and their counter part are powerless ones," buffer's Leo Widrich writes, adding that the difference between the two "goes a lot further than to just change the positioning of your legs or arms. Cuddy explains that inside our bodies, actual changes are happening as our body language changes. These changes largely have to do with hormones."

Power poses, where we spread our bodies wide or lean back in a relaxed, open manner, actually raise testosterone, which it turns out, significantly changes your demeanor. How do we know? Cuddy not only measured hormone levels but also asked research subjects to perform power or powerless poses before interviewing for a job. Those that used power poses prior to the interview were consistently rated more favorably by recruiters asked to evaluate them.

What's the takeaway of all this? If you have a big meeting coming where you need to impress, it might be worth your while to spend a couple of minutes practicing power postures beforehand. OK, it'll probably feel pretty silly, but science says it will boost your confidence, so if you're interested in giving it a try, check out buffer for images of the postures.

And you don't have to take one blog's word for the effectiveness of changing your body language. It's a big theme of Facebook COO Sheryl Sandberg's book Lean In as well. In it she urges women especially to focus on using their body language to convey confidence and power.

Do you find how you stand affects your state of mind?