by Everett Johnson, DC, ART Replacing the office chair with an exercise ball. The exercise ball has been employed as a tool to help individuals work on core muscle strength and rehabilitation. Though it is used as a tool to help with these exercises, there seems to be little research evidence to support the claims. This does not imply using an exercise ball for exercise is a bad thing, it just has not received the research attention of some other methods. The use of the exercise ball has slowly transitioned to the workplace to replace the solid and static office chair. Seated computer work results in prolonged static loading, which has been associated with the development of musculoskeletal disorders 1. Again, we find little evidence in the literature and little research in this area, but the majority of the literature available is in favor of the exercise ball. Claims are made of activating postural muscles while sitting on an exercise ball, which makes us think that muscles are relaxed when sitting in a chair.
According to a study published in Clinical Biomechanics (2006) 2 , would have us believe that this is a false claim. This study looked at muscular activation, posture, spine compression and stability while sitting on an exercise ball versus sitting in a regular chair. They also looked at the pressure differences created at the seating surface for the two, to correlate any perceived comfort levels. The subjects sat on an exercise ball for thirty minutes, then a wooden stool for thirty minutes and readings for muscle activity, posture and compression were taken for both groups. What they found was there was no significant difference between muscle activation between sitting on a ball or on the chair. They also found that pressure distribution was greater on the ball due to an increase in contact area and created discomfort for the subjects. An updated study published in Applied Ergonomics, March 2009 1, examined the differences in stable and unstable sitting environments for female computer workers.
They measured posture, muscle activation, and spinal shrinkage in ten female office workers for a one-hour typing task. The women were sitting in regular office chairs with arm rests, or sitting on an exercise ball. The findings of the study showed an advantage for the exercise ball as the women had 33% more trunk motion and 66% more variation on lumbar EMG. An increase in motion is a good thing, especially when one has a sedentary job. Constantly changing position is important to promote flow of nutrition to the intervertebral disc 3. The subjects of the previous studies did not suffer any low back pain, so a good question to ask is “what is the effect on people with reported back pain after switching to an unstable sitting surface?” An article published in the Journal of Canadian Chiropractic Association, March 2007 of a case presentation of two patients with reported low back pain and their outcome after switching from a stable to and unstable seating surface shows some positive results.
Both patients in the report suffered from low back pain, and both improved when they began to consistently use the exercise ball to sit on 4. Another study from the European Journal of Applied Physiology, June 2008 looked at the difference in energy expenditure through the work day when sitting in an office chair, sitting on a exercise ball or standing. Not only did they perform their clerical duties in each of the three positions, they were told to pick one of the three to perform twenty minutes of extra work. The subjects in the study expended an extra 4.1 kcals/hour while sitting on the exercise ball than sitting in a regular office chair. Not only did they burn more calories through the day, at the end of the day when they got to choose a sitting surface for the extra work, the majority of them picked the exercise ball 5. An interesting article was published in the American Journal of Occupational Therapy, September 2003, looked at the effects of having children with ADHD sit on exercise balls in the classroom.
The study looked at the behavior and handwriting of the children while sitting in a regular classroom chair and then sitting on exercise balls. What they found was the children displayed better in-seat behavior and more legible handwriting when sitting on the exercise balls 6. It was found that the teachers and the students preferred the exercise balls. Most of these articles have focused on someone sitting on a ball for a determined period of time and some have added tasks, such as computer work. This layout of the research is to add an element of control to the project. If everyone in the group being tested were free to do as they wish on the ball, I believe some of these outcomes would have been different, which doesn’t make for good research but, would probably give us more insight as to the true nature of people sitting on exercise balls at work. If you decide to replace your old work chair with an exercise ball, then use it. Don’t just sit there, slouched over like you would in your office chair.
Take advantage of the choice you or your employer has made and exercise on the ball at work. Simply start by doing a posture check every fifteen minutes when you make the transition. Posture check means that every fifteen minutes you are going to remind yourself to sit up straight, shoulders back, and breathing through your abdomen. Slouched over, shoulders rounded forward and shallow breathing from the rib cage is a sympathetic position for your body to be in and can cause more stress to your body. As you progress, perform a posture check every thirty minutes, then every forty five minutes, until it just comes naturally. When you have mastered your posture start challenging yourself to do some very simple exercises through the day as you work. Start using it for what it is made for, helping you work your core. You don’t have to do crunches, reverse crunches or anything that would be awkward to do at work, do simple things. Gently rocking back and forth on your pelvis allows for low back and pelvic motion.
This activates one set of muscles and relaxes another. So you can activate or contract the abdomen to work it in this very simple move and at the same time relax your back muscles and give them a break. This simple rocking backward and forward motion also works the thighs, legs, and feet while stimulating the hip, knee and ankle joints. Activation of these structures will help tone and strengthen them, and as discussed earlier, joint motion helps to lubricate and nourish the joint. Your balance will also be taxed as you perform this movement by making you stay stable on the ball through the motion. Propioception is defined as your body’s ability to determine the position of muscles, tendons, ligaments, and joints. This input allows your body to make constant, graded changes in position of the body during our everyday tasks. Falls are a very common occurrence and are the number one reason people over the age of 45 visit the emergency room. According to the National Safety Council, approximately 30,000 Americans a week are injured by falling (most of those over age 65).
According to the Centers for Disease control 35 to 45% of older Americans fall at least once in a year. Not all reasons people fall are under our control, but doing some simple things can greatly reduce your risk. Exercises to improve strength, balance and coordination are one of the most important things we can do to help prevent falling injuries. An exercise ball is a great way to increase your stability. A study in 2002 found that with moderate instability, an exercise ball may permit some strength training 7. While maintaining your posture on the ball, simply straighten out one leg in front of you and balance yourself with the leg that remains on the floor. This action increases the sensory input from the joints still connected with the ground all the way to the spine to keep you from falling off of the ball. (Disclaimer: The first time you try this hold on to something so you do not fall off.) At the same time you are increasing the proprioceptive input from the leg on the ground, you are strengthening the leg you are holding in from of you.
I think the expression goes, “two birds, one stone!” There is not an overwhelming amount of research on using an exercise ball as a replacement for an office chair. But, what is available is more positive than negative. The exercises presented are just a few examples of activities that can be done at work if you decide to make the transition from office chair to exercise ball. Something to keep in mind, no matter what you are sitting on, is that motion is good. Get up and move through your work day if it is possible. Do some stretches on your way to your coffee break, take a walk at lunch. Remember, motion is life. 1.Kingma I, van Dieen JH. Static and dynamic postural loading during computer work in females: Sitting on an office chair versus sitting on an exercise ball. Appl Ergon 2009, Mar; 2. McGill SM, Kavic NS, Harvey E. Sitting on a chair or exercise ball: various perspectives to guide decision making. Clin Biomech 2006, May; 3. Wilke HJ, Neef P, Caimi M, Hoogland T, Claes LE.