They’re working longer days and clocking weekend hours, but nearly nine in 10 employees are still happy at work and motivated to rise in their organizations, according to a new report from Staples Advantage, the business-to-business arm of Staples, Inc.

The study was not all positive, however. Twenty percent of all workers surveyed and 25 percent of millennials said they expected to change jobs in the next year. Many said they feel chained to their desks during the workday, and 53 percent say they are feeling burnt out.

About half of employees polled said that they feel they can’t get up for a break at all, and just under half eat lunch at their desk.

Related: The One Quick Way to Boost Worker Productivity

“While many are still happy at work, we have to ask whether it’s because they’re truly inspired and motivated, or simply conditioned to the new reality?” Dan Schwabel, founder of WorkplaceTrends.com said in a statement. “Either way, employers need to adjust to win the war for talent and optimize productivity, engagement, and loyalty with employees.”

A quarter of employees say they are working after the standard workday has ended, and about 40 percent work at least one weekend per month. More than a third of workers say they put in those extra hours in order to finish work they didn’t have time to get to, and 22 percent say it’s because they want to get ahead for the next day.

The survey also looked at factors that erode employee productivity, with workers citing email overload and inefficient meetings as top factors. One if five workers said that they spend more than two hours per day in meetings.