This is a series on arm and hand pain causes. If you missed the beginning, go back to the Checklist.

Local overuse for prolonged periods of time is what is known as Repetitive Stress or Repetitive Strain. Muscles that are given more work to do than they have energy or nutrient reserves to accomplish, will become sore, or worse, injured and painful. These conditions concern me greatly. I treat them weekly in my Neuromuscular Therapy center near Boston.

In our computer generation, local overuse of the muscles of the arm and hand is like an epidemic. Work deadlines that require many hours of overtime or working under stress are common in this competitive environment. Social networking that encourages texting is another source. How many people do you know who use their thumbs for hours on end this way. Computer games are a common source of overuse. When people get caught up in a game they can get lost so absorbed that they’re not aware of their bodies. Same for those who get lost in the cloud, spending hours in their heads with their hands on the computer keyboard without regard or care for how their bodies feel. Musicians practicing for hours on end to excel are candidates for injury. There’s even a branch of medicine know as “Performing Arts Medicine” that addresses these issues.

The muscles of the arm and hand are not meant to do heavy work. They aren’t large, like the thighs or the upper arms. Because they don’t have bulk to push through extra work, the existing fibers get overworked. When they get injured, there isn’t any more muscle to take over the load, so injured muscles must continue to work under duress without reserves. Like running out of gas in the tank, the muscles run out of fuel, or like running out of oil in the engine, they get “hot” and seize up.

To prevent injury, muscles need frequent breaks to recruit “food” molecules, change in the way they are used to get a little rest and cool down, stretching to reduce tension and open space for nourishing and lubricating fluids to flow, cardio exercise to increase general blood flow and get the “feel-good” chemicals pumping. All of these measures give muscles enough energy, nutrients and oxygen to do the work you give them, and time and space to clear away the waste products they produce that can damage the tissue and cause pain.