The findings, published in the Journal of Personality and Social Psychology, suggest a plethora of options presented to modern consumers may zap stamina and lower productivity.

The results -- based on seven experiments involving 328 participants -- were field tested in a mall with 58 consumers.

"Maintaining one's focus while trying to solve problems or completing an unpleasant task was much harder for those who had made choices compared to those who had not," lead author Kathleen Vohs of the University of Minnesota said in a statement. "This pattern was found in the laboratory, classroom and shopping mall. Having to make the choice was the key. It did not matter if the researchers told them to make choices, or if it was a spontaneously made choice, or if making the choice had consequences or not."

In the laboratory experiments, participants were asked to make choices about products, courses or materials while others did not have to make decisions but simply consider the options put in front of them.