02/25/2013 07:55 pm ET Updated Feb 26, 2013

Flexible Work Is Healthy , Studies Show

Marissa Mayer, CEO of Yahoo!, enacted a policy this week that requires previously remote workers to now spend their days in-office and bars employees from using flexible work hours.

"To become the absolute best place to work, communication and collaboration will be important, so we need to be working side-by-side ... That is why it is critical that we are all present in our offices," read the memo written by head of HR Jackie Reses and obtained by AllThingsD. “Speed and quality are often sacrificed when we work from home.”

Employees and the general public alike were dismayed by the news -- particularly as many companies move toward more flexible work hours, influenced by reports that a looser work schedule is healthy for workers -- and for the bottom line. Even the White House has compiled a comprehensive report, extolling the attributes to wellbeing of flexible work policies.

It should come as no surprise that Mayer, known for her hard-charging work ethic and two-week maternity leave, would prefer an all in-house staff. But are flex hours merely a luxurious refuge for the underperforming or, in the current work culture, a necessity for many in the workforce?

Research on employees who use flexible hours and work from home points toward the latter. Studies regularly show that employees who are given some choice as to their schedule and location of work report better self-care behaviors like increased exercise and regular doctors' visits, better sleep habits, less stress, less depression and less work-life conflict.

A 2010 Cochrane research review looked at the results of 10 studies evaluating more than 16,000 people. They found that self-scheduling work time improved a variety of health metrics, including reduced exhaustion, improved sleep (both duration and quality), lowered blood pressure, improved mental health and better self-rated health status. The distinction of self-scheduled, meaning the choice belongs to the employee, is important to note: As the authors wrote in their report, "In contrast, interventions that were motivated or dictated by organizational interests, such as fixed-term contract and involuntary part-time employment, found equivocal or negative health effects."

"Flexible working seems to be more beneficial for health and wellbeing where the individuals control their own work patterns, rather than where employers are in control," review author Clare Bambra, of the Wolfson Research Institute at Durham Univerisy in the UK, said in a statement. "Given the limited evidence base, we wouldn't want to make any hard and fast recommendations, but these findings certainly give employers and employees something to think about."

One well-known study looked deeper into the health impact of flexible work environment by following 608 white-collar workers at the headquarters of Best Buy before and after a flexible “Results Only Work Environment” policy was implemented. The researchers found that, on average, employees got one additional hour of sleep per work night after flex-hours were implemented and were more likely to exercise. They were more apt to go to the doctor when they needed to and were less likely to go into the office when contagious. From a mental health standpoint, the subjects reported that they felt "greater mastery" of their time, had fewer work-life conflicts and, as a result, felt increased energy, less stress and a self-reported sense of well-being.

"Flex time is a way to get control over work. We can't reduce the overload of tasks, but flexible schedules make it a bit more manageable," co-author of the Best Buy study, Phyllis Moen, Ph.D., McKnight Presidential Endowed Chair of Sociology at the University of Minnesota tells HuffPost. "We're expected to work smarter, do more with less and with fewer people. And what has enabled workers to continue to work with this level of intensity is often that they now arrange when they work."

"And yet I can't imagine [Mayer] will tamp down on the intensity of work," Moen adds. "What she's asking for isn't just a relocation shift -- she's ratching up time pressures when you want to be more flexible. Time pressure has a negative effect on people who are going to be expected to work long hours."

Further, many of the employees affected by Mayer's new policy are already accustomed to working on their own schedule and in their own environment. What will happen to the health of workers who have grown accustomed to flexible work hours and must now return to their office desks full time?

"We have no studies looking at what happens when you take it away, but the assumption would be that it would have negative effects," says Moen. "It will mean a lack of control -- and feeling a lack of control over one's life is associated with greater psychological stress."