MUSCLE OVERUSE
Muscle overuse or tendinitis occurs when you ask a muscle to do more than it is ready to do. I think of this as a personality problem. People who overuse make the activity they are doing more important than their body. It is a common problem. I see it alot in people who crochet, knit or garden for example. In these types of activities, people will put on blinders and just keep doing their activity regardless of what their body is telling them. When you feel discomfort or pain as you are contracting a muscle, it typically means you have done too much.
I have often heard from patients telling me “I have to” keep doing the activity that is causing the problem. Actually, the only “have to do” activities are to eat, drink, sleep, urinate, and move your bowels. Everything else is a choice. Let me clarify that I understand things need to be done, like feeding animals or your family. My recommendation is to ask for help to get these tasks done.
HOW A MUSCLE WORKS
A muscle that attaches to the skeleton is under voluntary command or needs a signal from the brain to work. Muscles that do not attach to the skeleton such as the heart or smooth muscles in vessels are automatic and work without needing a command. Skeletal muscles are made up of individuals fibers which are made of muscle cells. These fibers can be seen in shredded meats. Muscles attach to bones on each end through a white fibrous tendon made of collagen. The skeletal muscles have a nerve that gives a command and tells the muscle to contract or fire which shortens the muscle and makes it thicker in the middle. This pulls the two bones toward each other.
This photo shows a group of muscle fibers attaching through white tendons to two bones.
Muscle Fibers Intact
This photo shows a muscle that is contracted pulling the bones together.
Muscle Fibers Contracted
MICRO-TRAUMA
Each muscle has a certain number of energy tokens or times it can contract or fire. When that number is exceeded some of the small fibers can be popped letting go of the tendon. For example, if a muscle has the ability to contract 10 times a day and you contract it 12 times a day, a few fibers will pop. These micro-traumas are not typically a problem because as you rest the muscle such as sleeping, they repair.
This photo shows a few fibers popped away from the tendon.
Muscle Fibers Torn
If the muscle with a micro-trauma is continued to be used too much more fibers pop away from the tendon.
Muscle Fibers Greater Tear
MACRO-TRAUMA
When an overused muscle is continuing to be taxed, it eventually will completely tear and pull the muscle away from the tendon. This is called a rupture. A rupture can also occur with a large trauma or accident.
Muscle Fibers Ruptured
PREVENTING MUSCLE OVERUSE
Any skeletal muscle can be overused. By starting slowly and building gradually when increasing muscle use or strengthening, you can prevent overuse. If a muscle is able to contract 10 times in a day and you only fire it 8 times then you will not overuse it. When you are very weak and ready to progress an exercise program or an activity, I recommend starting with only five repetitions of an exercise or five minutes of activity. Every few days add a few more reps or another five minutes of activity.
If you are fairly well conditioned, it is OK to start with 10 repetitions or 30 minutes of activity. Regardless of where you start, you want to build slowly and gradually. Rest between exercise episodes and sleep well to repair any damage that occurred during the use of the muscle. When you take a break from exercise or activity for longer than 4 days, it is important to slow down from where you left off and gradually build back up.
Working to be able to run a marathon is a good example of proper exercise practice. They start with walking or running 2-5 minutes for 1/2 mile then every few days or at least once a week they add a little more. Eventually, they are running several miles. Getting closer to the time of the marathon, they will mix it up doing 15 miles one day and 3 miles the next day. Finally, they run the marathon at 26.2 miles. But they will last best and prevent overuse by building slowly and gradually. Strengthen any muscle this way to prevent muscle overuse and pain.