If a man wants to bring a rival down a peg or two, he simply has to hold the door open for him.
While the gesture of goodwill might be seen as gentlemanly when it is done for a woman, psychologists claim it is likely to diminish a man’s self esteem.
Since it is unusual for men to hold open the door for men, it could be taken to imply that the recipient looks needy and vulnerable.
The act is likely to clash with their masculine identity and leave them deflated, Professor Janice Kelly and Megan McCarty, of Purdue University in Indiana, suggested.
Their study, published in the journal Social Influence, found no evidence that women were affected in a similar way when men held doors open for them.
“These results demonstrate negative consequences of seemingly innocuous… helping behaviour that violates gender norms,” the researchers said.