Factors Affecting Muscle Tension

1. Sleep

Inadequate sleep increases the activity of the nervous system, including the nerves going to the muscles, due to lack of rest and the fact that you’re pushing yourself to keep going when you’re overtired.

During sleep, extra oxygen is supplied to the muscles and this assists in the breakdown of lactic acid. When you aren’t getting enough sleep, lactic acid builds up in the muscles causing knotted "trigger points" to form. During sleep your body also heals any minor tears which occur in the muscles during the day. Without adequate sleep, you get behind in your healing, and problems build up.

2. Exercise

Cardiovascular exercise also increases the supply of oxygen to the muscles, but does it much more quickly than occurs during sleep. Low oxygen levels in the muscles from lack of exercise causes lactic acid to build up causing knotted "trigger points" to form.

Also, muscles which have become weak from lack of exercise are easily overworked causing muscle soreness which in turn leads to muscle tension. Finally, when muscle stretching is neglected the muscles become shortened, and knotted "trigger points" will develop.

3. Diet

Can a poor diet cause muscle tension? Most Certainly! The four most important factors are calcium, caffeine, phosphorus, and vegetarianism.

a) Calcium. Lack of calcium and to some degree magnesium in the diet reduces the "slide back" of the muscle fibers (in the relaxation phase of contraction), after they slide together during contraction. Some of the muscle fibers "lock" in the contracted position, causing chronic muscle tension in all your muscles (throughout the body).

b) Caffeine. Caffeine is a stimulant. Too much caffeine in the diet stimulates the nerves that control muscle activity, causing the muscles to partly contract and stay that way. This, in turn, increases the muscle tension. Caffeine also has a diuretic effect, causing increased urine production. The water lost in the urine contains minerals. The most important minerals for muscle function are calcium and magnesium. The loss of calcium and magnesium due to the diuretic effect of caffeine increases muscle tension in a similar way to a diet low in calcium and magnesium, even in those with adequate calcium and magnesium in their diet. Problems caused by muscle tension are compounded by both the stimulant and diuretic effects of caffeine. In order to maintain the calcium levels in the blood, your body will dissolve ("steal") calcium from the bone marrow, and this can eventually lead to osteoporosis (thinning of the bone).

c) Phosphorus. Too much phosphorus in the diet can also contribute to muscle tension. The number one source of phosphorus in the North American diet is cola drinks. Phosphoric acid in these drinks "leeches" calcium out of our systems, making less available for muscle relaxation (as well as less available for building strong bones and teeth). Thus, cola drinks have a triple effect on muscle tension: the stimulant and diuretic effects of caffeine and the calcium loss caused by the phosphoric acid.

d) Vegetarianism. Those who follow a vegetarian diet will often be deficient in vitamin B12, making the muscles more "irritable" and more likely to be chronically tense.

4. Nerves

Excess activity of the nervous system can also be a contributing factor to muscle tension. This is often found in people who have too busy a schedule, or who have too many things to do and not enough time to do them all.

These people may want to "have it all" or will try to be "all things to all people". Their hectic schedule may also be due to factors beyond their control, such as a parent, spouse, or child who is ill, and requires a lot of emotional support as well as help with household chores and personal care. This often makes their already hectic schedule unbearable.

5.Cold

Exposure to cold and wind causes a loss of body heat which in turn causes us to unconsciously tense our shoulder muscles, and pull our shoulders up towards our neck. This contraction of the muscles above our shoulders produces heat to keep us warm, and protects the neck (and to some degree the head) from heat loss.

If the heat loss is great enough, we will start to shiver. If the exposure to cold continues long enough the tension and shivering will cause lactic acid to build up in the muscles, causing knotted "trigger points" to form. This can happen just as easily on a windy summer evening or indoors in the summer where cool air from the air conditioner is blowing on you, as it can outdoors in the winter, or indoors in a poorly heated building.

6.Smoking

Although smokers report short-term tension relief from smoking, the long term effect of smoking is to gradually increase muscle tension (not to mention the effect on the lungs, heart, and blood vessels).

The short-term relief of tension smokers receive is due to the analgesic or painkilling effect of nicotine. However, smoking increases the levels of carbon dioxide and carbon monoxide on the blood, while at the same time decreasing the level of oxygen. Decreased oxygen in the blood causes lactic acid to build up in the muscles, causing knotted "trigger points" to form.

7.Rest and Relaxation

The effect of inadequate rest, relaxation, and holiday time on muscle tension is the same as that of excess work and overtime. You need both a mental break and a physical break from your work in order to relax.

If you don’t get an occasional break from your work, tension builds up in the muscles just like it does from lack of sleep. You will also become stale and stagnate in your work. A regular break will not only decrease your tension levels, but also make you more productive when you return.

8.Mental Fatigue

Mental fatigue from worrying, frustration, and anger can also contribute to muscle tension. Illness of a parent or other family member, financial trouble, job problems, difficulties with family relations, and any other type of unresolved problem can all contribute to mental fatigue.

The worry, frustration, or anger they produce causes an increase in activity of both the nervous system and the endocrine glands. Excess activity of the autonomic nervous system, which controls resting muscle tension, causes chronic muscle tension. Excess activity of the endocrine glands, such as the adrenals, thyroid and pituitary, during the day will carry over into the night, causing difficulty relaxing and difficulty sleeping.

Resolving the problems that are worrying, frustrating, or angering you will not only make you more energetic, but also help to reduce your muscle tension.

9.Posture

The final factor contributing to muscle tension is poor posture. When we have good posture, our spine is in a balanced position, and requires very little muscle activity to hold it upright.

Like a balanced pole which pulls very little on the guy wires that steady it, the muscles hardly have to work at all. However, when we slouch, the spine is in an unbalanced position, and requires constant muscle activity to keep it upright.

Like a tilted pole that pulls very hard on some of its guy wires, and not at all on others, the muscles are working against gravity all the time.

Contact Dr Millar today for more information

Return to Millar Sports Chiropractic

Back to Millar Sports Home Page

Patient Reviews:

"After looking over the nutritional advice I was given, I changed my diet immediately.
As a runner, you don’t want to limit yourself. Knowing when to eat – what to eat – what NOT to eat – has definitely given me an added advantage and benefited my performance."

Magda Badura – Marathon runner

"If you have any questions about nutrition, or how to train properly – you’re always given great advice. You trust it works because he’s tried it himself."
I’ve learnt how to eat properly – what foods to eat for a competition and what not to eat."

Paul Kwatyra – University student and Varsity team swimmer