You walk to the mailbox and start to feel shin splints. As you head out for your morning run, your calf muscles begin to tighten up and spasm. Both athletes and non-athletes experience muscle cramps and spasms for the same reasons. The athlete may bring theirs on sooner, while it can be a slow buildup for other people. Here is why you get muscle spasms and how to avoid them from slowing you down.
How Muscles Work
The muscles that help you move are fibrous tissues that connect to your bones by a tendon. These fibers expand and contract, allowing the muscle to stretch or shorten. Muscle fibers contain a protein, called myoglobin, which carries oxygen to the muscle cells. Your bloodstream provides electrolytes and glucose to the cells. Oxygen, electrolytes and glucose are all needed for muscles to move. When any of these are depleted, muscles become exhausted and can begin to cramp or spasm.
Creating Muscle Spasms
When you push a muscle to work hard without warming up, the immediate supply of energy is used up quickly, starving the muscle. Holding a muscle in a tightened positioned for a long time uses up its energy faster than the body can supply it back to the muscle. Both conditions cause your muscles to react by stretching and tightening rapidly (spasms) or to contract suddenly and hold itself in that position (cramps).
This can happen when doing a normal level of physical activity in hot conditions. Working or exercising in a hot environment depletes the muscles of nutrients sooner. An athlete is vulnerable to spasms when competing in hot climates.
Dehydration reduces the fluid in the muscles that carries the electrolytes to the cells. When the sodium, potassium, calcium and magnesium levels fall below normal in a muscle, the fibers contract violently.
Muscle spasms last for a few seconds and may repeat over a period of time. Cramps occur suddenly, violently and may last several minutes. Both contract the muscles so you'll feel the need to slowly stretch them out. They can also have various levels of pain from barely noticeable to severe leg cramps which prevent you from walking.
Treatment and Prevention of Muscle Spasms and Cramps
The two goals of treatment are:
- relieve the immediate muscle contraction and pain
- fortify the muscle to prevent a recurrence
A sports medicine physician teaches athletes how to prepare their muscles for activity. These techniques work for the non-athlete who is susceptible to muscle issues, as well:
- Slowly stretch the muscles which increases the circulation and the supply of oxygen and electrolytes to the cells.
- Keep the muscles hydrated by drinking water or an electrolyte replacement - drinks containing caffeine stimulate urine production and can dehydrate the muscle cells.
- In hot climates, more aggressive hydration and giving your muscles frequent rest periods is important.
The treatment of existing cramps and spasms includes:
- hot packs to warm up the muscle fibers causing them to stretch
- cold packs to relieve the pain, usually in the deep muscle areas
- physical therapy to slowly stretch the muscles out
- transcutaneous electrical nerve stimulation, or TENS, which reduces the nerve irritation that produces spasms
Preparing your muscles for activity is the best way to prevent spasms and cramps, especially in hot environments. Keep hydrated and your electrolyte levels up. If you seem to get spasms or cramps with no physical activity, see your doctor. You may have a dietary lack of one or more of the electrolytes or a medical condition which restricts these energy-producing substances to your muscles.
For more information, contact Active Orthopaedics or a similar organization.