by Bob Niklewicz
Did you know... There are over 600 muscles in your body?
Pop Quiz: To make a joint move, does a muscle: push, pull or do both? Time's up: The 600+ muscles in the body are designed for action, they are the motors of the body. Each muscle is made up many bundles of individual muscle fibers.
Dia. 1: The muscles attach on either side of each joint. Muscles only pull (contract/shorten) and, when they do so, they move the joint in one direction. Muscles do not push a joint. The muscles exert force by contracting to achieve motion. The muscle can generate the most power in its intermediate range. This middle range is often the neutral position of the joint.
Muscle components: Think of it like a co-axial cable with thousands of fibers. Each has its own nerve and blood vessels It attached to the bone via a tendon.
Dia. 2: Shows the right elbow. The backside muscle is called the triceps and the front side muscle is called the biceps. When the triceps contracts the elbow goes out straight. When the biceps contracts, (see diagram) the elbow bends. When they contract at the same time the elbow is held in a tight, “isometric” or “co-contraction” at any position. There are 40 back muscles that can set and brace themselves against heavy loads. If the muscles are weak, poorly trained, or fatigued, they will not be adequate to support the back during lifting or to protect the back against a sudden and unexpected movement. A healthy degree of muscle strength does not mean that they must be big and bulky, just able to do normal tasks. (More information in future articles.)
There are different types of muscle:
Dia. 3: Cardiac fibers have cross links between the fibers. They work all the time– until they stop.
Dia. 4: The smooth muscles contract around your blood vessels and your intestines.
Skeletal muscles produce locomotion and are tubular and in bundles. For the purposes of this article, skeletal muscle function will be our only concern. With a hard skeletal muscle contraction, 60% of the circulation can be cut off from the nutrient pathway that will lead to fatigue.
If the contraction is sustained for a period of time and the muscle is injured, there is usually a tear in the fibers with bleeding into the surrounding tissue. A tear is called a strain. Dia. 6 illustrates a tear in the thigh muscle. They can range from a partial tear to a complete tear. (Far right figure-an awful situation.) To heal a minor strain, the body has to dissolve elements of the blood that leaked out and carry them away, then grow a patch fiber. This takes 4-6 weeks to return to full function depending on the extent of the strain. The process is often accompanied by an itching sensation. Gentle massage is best, don't scratch. Prevention is the best treatment initially, otherwise, using ice packs for brief periods of time will reduce the pain and swelling. Since not all ice packs are the same temperature, (they can range from 0° to 31°) it is best not to time the application of the ice, but rather feel when they should come off. Switch to warm packs if needed after 3 days. Returning to light activities will help the circulation and healing. To chill a strain, place a damp cloth over the sore area, then apply the ice pack. Note: It will start to get really cold, it will progress to a burning sensation, after that it will feel numb. That is when you remove the pack. Damage to the skin can occur if the ice is left on too long. Too long is when it starts to feel warm again. So, be cool not frozen. Your skin and muscles will thank you. If all goes well, there will be days when all 600 muscles seem sore at the same time. “They hurt good!” –That means you probably had a good day in the garden. Take the next day off, you'll need it.
Napa Master Gardeners are available to answer garden questions by email: mastergardeners@countyofnapa.org. or phone at 707-253-4143. Volunteers will get back to you after they research answers to your questions.
Visit our website: napamg.ucanr.edu to find answers to all of your horticultural questions.
Diagrams: Vecteezy.com
