Instead of passively sitting, you'll be actively balancing. Over time you'll burn more calories, improve your posture and increase your core strength. It sounded easy. Could something that simple really work?
One of the first published studies that replaced chairs with exercise balls was done in 1992 on school children. The aim of the study was simply to "determine the value of a new type of seating accommodation – a large plastic ball." In one school year 162 children used the ball and a similar group of 148 children used normal chairs. At the conclusion of the study the researchers said:
"The results suggest a possible effect of the new seating accommodation on the back and abdominal muscles, but on the whole we found little improvement due to the ball alone."
The ball didn't really seem to be better than a chair, so interest dried up.
Fast forward to the year 2006, suddenly exercise balls are everywhere. Personal trainers use them to target abdominal muscles, yoga and pilates instructors use them to build core strength and gyms started setting up dedicated areas where they can be used. Exercise balls were hot and the companies that made them wanted to sell more. So in an effort to expand their sales, they started marketing them as healthy chair replacements. Clinical researchers disagreed.
In a study carried out in 2006 at the Department of Kinesiology, University of Waterloo in Ontario, Canada they concluded:
"The results of this study suggest that prolonged sitting on a dynamic, unstable seat surface does not significantly affect the magnitudes of muscle activation, spine posture, spine loads or overall spine stability. Sitting on a ball appears to spread out the contact area possibly resulting in uncomfortable soft tissue compression..."
In other words, your muscles didn't get bigger, your spine didn't get more stable and sitting on an exercise ball made your butt hurt.
In June of 2008 the School of Medicine and Biomedical Sciences at the State University of New York looked into how many calories someone would burn while word processing and either
a) sitting in an office chair,
b) sitting on a therapy (exercise) ball, or
c) standing.
Adults ranked their comfort, fatigue and liking of each posture over a 20 minute test.
The good news is people who sat on an exercise ball or stood up burned an average of 4.1 calories more than the people sitting in a traditional office chair. The bad news is 4.1 calories is the equivalent of three Tic Tacs.
More bad news was delivered in early 2009 from the Faculty of Human Movement Sciences at VU University in Amsterdam. They "monitored posture, muscle activation and spinal shrinkage in 10 females performing a 1-hour typing task, while sitting on an office chair with armrests and while sitting on an exercise ball."
The subjects who sat on the exercise ball had 33% more trunk motion (that's good) but they also experienced more spinal shrinkage (that's bad). In the end they concluded, "the advantages with respect to physical loading of sitting on an exercise ball may not outweigh the disadvantages."
The Bottom Line
Exercise balls are a great tool when used for stability or core strength building exercises. Unfortunately they're not a good replacement for your traditional office chair. If you really want to burn more calories, set an alarm to get up and walk for 10 minutes every two hours. You'll burn more than 50 calories each time and get back to your desk feeling refreshed.
Despite the limited results, some people may still want to get a ball chair just so they can have a change. If you're just looking for something different, there are a few things you should keep in mind.
