Preventing and Recovering from RSI
Why Breaks Are So Important
By now, most computer users have heard that they need to take regular breaks to help prevent repetitive strain injury (RSI). There are many reasons why regular breaks are important; here are just a few.
OVERUSE LEADS TO MICROTRAUMA IN THE SOFT TISSUES
Sustained repetitive computer work fatigues the tiny muscles of the hand and forearm. Overuse can lead to micro-tears in the soft tissues, which can become swollen and painful. Swelling, in turn, can lead to pressure on the nerves, and conditions such as carpal tunnel syndrome.
Breaks and rest allow the body to repair itself; continued work perpetuates the damage. The longer the activity continues, the longer the recovery period is required and the greater the risk of chronic disorder.***
TENDON SHEATH INFLAMMATION
Repetitive movements can also damage tendons. When muscles and/or tendons are frequently tense, inflammation can result. Further strain can lead to tears in the tendons. If adequate rest is not taken, the tendon fibers cannot heal, and may be permanently weakened.***
Tendons glide within sheaths lubricated by synovial fluid. If this fluid is diminished or thickened from overuse or prolonged static postures, friction between the tendon and sheath can result. The sheath becomes swollen and inflamed, leading to pain. Repeated forced movement may cause the inflammation of additional tissues, which can lead to permanently swollen tendon sheaths.**
CIRCULATION IS IMPAIRED BY PROLONGED SITTING
When you sit in static postures, circulation can be impeded. When the blood flow to an active muscle is impaired, waste products accumulate and the oxygen supply is diminished, which can over time impair muscle function. The development of fatigue is probably related to the adequacy of blood supply.*
This tendency can be offset by getting up and walking around regularly during breaks.
COMPUTER WORK DISTORTS AWARENESS OF TIME
Most people do not take breaks frequently enough, nor do they have an accurate idea of how much time has passed since they began working. They need timed reminders to be sure they take regular breaks.
For people with RSI, taking breaks before symptoms appear is especially critical. If you wait until you're in pain, it's too late, because the cycle of pain, inflammation and injury has already resumed.
* "Physiologic and Biomechanical Factors for Understanding Repetitive Motions Injuries," David M. Kiser, Ph.D., Seminars in Occupational Medicine, March 1987
** "Avoiding Cumulative Trauma Disorders in Shops and Offices," K.H.E. Kroemer, American Industrial Hygiene Association Journal, September 1992
*** "The Application of Ergonomics to the Office Environment," Robens Institute, University of Surrey, UK