Short answer - yes!
There are some studies that back this up, which I'll get to shortly. However, firstly I'd like to discuss why, in my opinion as a WHS Consultant, standing up at work increases productivity.
In my experience, most people have a sitting tolerance of between 30 - 60 minutes. After this time, restlessness, irritation or discomfort results in the individual "wanting" or "needing" to change position. Once this occurs, the individual is unlikely to be able to concentrate on the task at hand, because their central nervous system is telling them to MOVE!
The reason this occurs is commonly because the body does not like staying in the one position for prolonged periods. Unfortunately, this is the usual way of things in traditional office settings.
Now to the research....
A study published in the IIE Transactions on Occupational Ergonomics and Human Factors, found that employees who had the option to use a standing desk were a whopping 45% more productive than those who didn't. For this study, they analysed the number of calls taken by employees in a call centre.
Another study, published in Occupational and Environmental Medicine, found that periodically switching between sitting and standing reduced fatigue levels by at least 15% and up to 33%, as well as reducing musculoskeletal discomfort by 31%. Both of these factors are crucial to productivity as they are directly proportional to how long an individual can concentrate on a particular task.
Further, a study published in Preventing Chronic Disease found statistically significant improvements in fatigue levels, vigor, tension, depression, confusion, and overall mood, in employees who used standing desks peridoically throughout the day for a 7 week period. At the end of the study period, 87% said they felt more comfortable, 87% felt energised, 75% felt healthier, 71% felt more focused, 66% felt more productive, 62% felt happier and 33% felt less stressed.
So, the research and clinical experience tends to suggest that standing desks can improve employee productivity. I'd like to point out that I do not advocate standing all day, because most people can't do it - and this itself would qualifiy as a prolonged posture, which standing desks are aimed at eliminating. Standing periodically throghout the day, for about 50% of the working day, is the way to go.
For help in progressing to a standing desk, please visit the "How long should I stand" article here.
If you have any questions, please email firstname.lastname@example.org.