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You don't have to stand all day long to escape the dangers of too much sitting—a public health threat that's been dubbed “the new smoking.” In fact, a new suggests that being on your feet for about half of your work day (four hours, to be exact) may be the magic number. 

The statement, published this month in the British Journal of Sports Medicine, first rehashes what we already know: Prolonged sitting is associated with heightened risk of serious disease and premature death. (It also saps energy, slows metabolism, and helps us pack on pounds.) Then, the authors outline the world’s first scientific guidelines on this subject. 

You should be standing or doing light activity (like walking) for a minimum of two hours every day during working hours, they say, eventually progressing to a total of four hours. You should also avoid prolonged periods of sitting, and regularly break up sitting and standing periods with the use of sit/stand desks or workstations. 

But is two or even four hours of standing really enough for desk jockeys who are on their butts the rest of the day—and, most likely, a good portion of their evening, as well? True consensus on this topic is still evolving among the research community, says , a PhD candidate at the University of Toronto and co-author of another recent on the effects of sedentary behavior. But he says these recommendations are a good first step for people of all activity levels. 

“Two hours of standing a day serves as a good starting target for people to aim for,” says Biswas. “Progressing up from that is a good thing and will most likely lead to reducing prolonged sitting-associated risks.” 

Two-plus hours a day of standing may sound difficult, but you don’t have to do it all at once. “Break up continuous sitting—every 30 to 60 minutes—with a few minutes of standing and moving,” Biswas says. 

Even if you're active outside of your workday and you exercise regularly, these guidelines still apply. You're probably at lower risk for health problems than completely inactive people, says Biswas, but the dangers of prolonged sitting still apply to everyone. “The aim should be to complement your active lifestyle with less sitting throughout the day.”

Bottom line: Aim to be on your feet for at least two hours total—working your way up to four hours—during your workday. An adjustable-height desk may help you achieve that goal, or you could get creative: Take frequent standing or walking breaks, drink plenty of water so you'll have to make regular bathroom trips, or do non-computer tasks (like eating lunch or talking on the phone) while standing. Just don't think standing more during the day lets you slack off during your free time. “The benefits of sitting less can only truly be realized if we're also exercising regularly,”Biswas says.