Proper Sitting Posture
By Allan O. Fiesta, PT, DPT
Proper Sitting Posture
Ergonomics can be generally defined as the study of people’s efficiency in their working environment as it pertains to improving body mechanics by modifying their work space to prevent further injury. Whether you are an elementary school teacher or electrical engineer, proper sitting posture is very important and should be observed and adjusted properly to accommodate each persons work station in order to prevent musculoskeletal injuries which can likely cause neck and/ or low back pain. Proper posture involves modifying your work station as well as re-training your body to sit, stand, and lie in the position where the least amount of strain and/ or stress is placed on the supporting skeletal structures, surrounding musculature, and ligaments.
In observing the correct sitting posture, shoulders should be down and back. Head should not be leaning forward but inline with the body, so that you are sitting as upright as possible with your bottom all the way to the back of the seat (roughly 90-120 degrees of hip flexion). When sitting at a desk, one should sit at a height where the elbows should be close to the body and at about the level of the keyboard or table top to avoid shrugging and stress to the shoulder complexes (elbows should be at about 90-120 degrees of flexion). One may adjust the back of the seat for good lumbar support by using a chair which has a contoured back rest or implementing the use of a small lumbar pillow. These simple modifications to one’s work chair can be used to accommodate the natural curvature of the spine as well as provide support to the lumbar spine when sitting for extended periods of time. If one’s chair has armrests, one may try to adjust these so that the armrest supports the arms in this neutral (90-120 degrees of elbow flexion). While sitting, if one’s feet do not reach the floor comfortably or there is pressure along the back of the legs, one may use a footrest to help off load the pressure behind the knees to avoid occluding blood vessels in the back of the knee.
When looking forward at the computer or tablet monitor, the top of the viewing area should sit either at or below one’s eye level. The distance from the monitor to one’s head should be roughly an arms length away from the screen to avoid excessive cervical flexion or extension when sitting in this neutral position. Next, locate the mouse next to the keyboard and make sure that both elbows are by the sides while work. One may use a mouse pad or another soft surface to pad edge of the desk which will aid in avoiding excess pressure on the hands or forearms against any sharp edges on desk.
With one’s elbows now comfortably resting on the desk top or keyboard level, the wrists should be straight or in a neutral position where they are able to gently rest in front of the keyboard or mouse. One may use a wrist rest if desired to achieve this optimal wrist position when using desk top accessories such as a mouse. However this is not always necessary.
Last but not least, when fine tuning the ergonomics of one’s desk space, it is important to take breaks from sitting every 30 minutes to ensure proper blood flow and reduce fatigue by increasing oxygen to the brain. Though we as a society have a tendency to get caught up in on the computer until the final hour, it is important to remember that subtle modifications to one’s work station and daily routine can go along way in reducing the risk for lower back or cervical injuries in the work place.
To read more about how computers can affect your low back visit: