It happens every day: Office workers find their eyes glazing over as they stare at their computer screens and head to the vending machines to get a soda or cup of coffee. They may want to reconsider and climb a few flights of stairs instead. It will do a better job of shaking out the cobwebs.

This was the finding of a study designed to mimic a typical office setting, where workers spend hours sitting and staring at computer screens and don't have time for a long bout of exercise during the day. On separate days researchers had participants either ingest capsules containing caffeine or a placebo, or spend 10 minutes walking up and down stairs — about 30 floors total — at a low-intensity pace.

Stair walking was associated with a small increase in motivation for work.

“We found, in both the caffeine and the placebo conditions, that there was not much change in how they felt,” researcher, Patrick J. O'Connor, said in a statement. “But with exercise they did feel more energetic and vigorous. It was a temporary feeling, felt immediately after the exercise,” but the boost they got was greater than that from caffeine.

Why stairs? “A lot of people working in office buildings have access to stairs, so it's an option to keep some fitness while taking a short break from work.” explained O'Connor. And they can be used even in bad weather, no showering necessary.

The subjects were female college students who described themselves as sleep deprived, getting less than 6½ hours per night. University of Georgia researchers had women in both the caffeine and exercise groups take verbal and computer-based tests to gauge how they felt and how well they performed certain cognitive tasks. Neither caffeine nor exercise resulted in large improvements in attention or memory, but stair walking increased motivation for work.

“You may not have time to go for a swim, but you might have 10 minutes to walk up and down the stairs." O'Connor added. “[E]ven a brief bout of stair walking can enhance feelings of energy without reducing cognitive function.”

The study is published in the journal Physiology & Behavior.