Your aching back or burning eyes may tell you that taking a break from your work is a good idea, but there’s very little research to suggest when, how often, or how long you should break for maximum benefit. To fill this gap in knowledge, two associate professors of management at Baylor University’s Hankamer School of Business set out to investigate what exactly constituted a “good” work break.  Emily Hunter and Cindy Wu surveyed 95 employees (ages 22 to 67) over a five-day week, and analyzed 959 break surveys. Their results were published in the Journal of Applied Psychology. “Everyone knows breaks are helpful, but there’s surprisingly little research on what makes the best break,” Hunter says.

Hunter and Wu defined breaks as “any period of time, formal or informal, during the workday in which work-relevant tasks are not required or expected, including but not limited to a break for lunch, coffee, personal email or socializing with co-workers, not including bathroom breaks.”

1. THE BEST TIME FOR A BREAK IS MID-MORNING. 

Hunter and Wu were surprised by the counterintuitive finding that afternoon is not the ideal time for a break. “We found that workers should take a break mid-morning, before lunch," Hunter tells mental_floss. "Morning breaks were the most effective at restoring resources of all breaks across the day.”

The research says that mental resources like energy, concentration, and motivation are highest in the first half of the day. Rather than waiting until lunch, when you’ve already burned through most of your brain fuel, take a short break mid-morning. Hunter and Wu found that this break brought employees back to their desks refreshed and energized, and with greater ability to endure the rest of the day.

“Your mental resources decline throughout the day,” Hunter says. “So when taking a mid-morning break you’re replenishing a small amount of lost resources better as opposed to afternoon, when it’s harder to get back to your pre-break state.”

2. EMPLOYEE AUTONOMY MAKES FOR BETTER BREAKS. 

Hunter and Wu’s results also turned up an important finding for managers. Structured breaks, or prescribed breaks—in which employees must follow someone else’s rules or expectations—are not as effective as breaks initiated by the employees themselves.

“We tested a number of assumptions, including going outside or doing something of low effort, not using a lot of physical effort, or doing something not work-related,” Hunter says. “None of those things mattered. The only two characteristics of break to replenish energy and reduce symptoms were taking break earlier in the day and doing something you prefer.” They found that the content of the break didn’t matter—whether it was exercise, eating, or simply walking away from one’s desk; what mattered was that it was “something you enjoy and choose to do.” They concluded that managers might see greater productivity and morale if they allowed their employees to take their own breaks. 

3. MORE BREAKS LEAD TO BETTER HEALTH AND INCREASED JOB SATISFACTION. 

The one finding that did not surprise either researcher was the confirmation that breaks are helpful. “They did replenish energy, concentration, and motivation. They decreased symptoms of headaches, eye strain, lower back pain and so on,” Hunter says. They determined that people who took these smaller breaks had higher job satisfaction, more citizenship behavior (helping others, going above and beyond in the workplace), and lower burnout—all important criteria for employers. Hunter feels this is crucial information for managers: “There hasn’t been a lot of research about the effects of breaks besides ergonomics that confirms the notion that they are effective.”

4. FREQUENT SHORT BREAKS ARE IDEAL. 

While a lunch break is always a good idea, and there is no magic rule for the perfect number of minutes, Hunter says they did find that “what matters is how many you’re taking.” The study pointed to more frequent short breaks as being most effective at reducing negative effects and boosting mental resources. They also found that those people who take an earlier mid-morning break are more likely to take more breaks in general.

Ultimately, the study suggests that managers institute more flexibility in scheduling breaks, and allow more autonomy to employees to listen to their own cues and break when they need to. For the employee, it might just mean that at the first sign of weariness in the morning, instead of reaching for that second cup of coffee, you just need to step away from your work.