Muscle cramps: prevention, diagnosis and when to see a doctor

A cramp can be relieved in a minute, but it is far more useful to understand why it recurs and to prevent it at an important start. In this material the editorial team has gathered practical approaches to prevention, an algorithm of actions during a spasm and a list of examinations worth undergoing if cramps have become frequent or atypical.

What to do at the moment of a cramp

The most effective and best-studied technique is passive stretching of the affected muscle. During a calf muscle cramp you need to pull the foot toward you with the knee straight; with a spasm of the back of the thigh - straighten the leg and lean forward; with a quadriceps cramp - bend the knee, pulling the heel toward the buttock.

Stretching activates the Golgi tendon organs, which inhibit excessive activity of the motor neurons. Usually the spasm eases within 30-60 seconds. Stretch smoothly, without jerks, so as not to damage the already strained fibers.

1. Stop the exercise or reduce the pace.
2. Smoothly stretch the affected muscle and hold the position until the spasm passes.
3. A light massage after relieving the cramp helps to relax the muscle.
4. If the workout is long and you have been sweating heavily - drink fluid with electrolytes.
5. Return to work at a lower pace or finish the session if the cramp recurs.

Popular folk remedies - pickle brine, mustard, hot extracts - have an interesting scientific rationale. Small studies have shown that sour brine shortens the duration of induced cramps even before it has time to be absorbed. The effect is probably related to reflex inhibition via the receptors of the oropharynx, not to replenishing salt. However, this is not a substitute for stretching.

After a strong cramp the muscle may hurt for several days. If the pain increases, swelling appears or the urine darkens - this is no longer an ordinary cramp, and a doctor is needed.

Prevention: training and recovery

Since the leading cause of cramps during exercise is considered to be neuromuscular fatigue, the main prevention is adequate preparation. A muscle adapted to a specific duration and intensity of work tires more slowly and less often breaks down into a spasm.

In practice this means a gradual increase in load, especially before competitions, and training at a pace and in conditions close to those of the start. Athletes who had cramps at previous competitions benefit from an analysis: was the starting pace higher than their real capabilities, was there a lack of sleep, did their nutrition change.

Regular stretching of the most frequently affected muscles is widely recommended, although there is little quality evidence of its preventive effect. It is probably useful primarily for people with shortened muscles. Strength work for the calves, the back of the thigh and the feet increases their resistance to fatigue.

Recovery should not be underestimated: sleep, sufficient energy value of the diet and carbohydrates to replenish glycogen. During a cutting period the risk of cramps rises, so the calorie deficit should be kept moderate and sharp manipulations with water and salt should be avoided.

Hydration, salt and supplements

Drinking as much as possible is not the best strategy. The position of the American College of Sports Medicine (ACSM, 2007) advises preventing a loss of more than about 2% of body weight through dehydration, but avoiding excessive water intake, which can lead to hyponatremia. The optimal volume of fluid is individual and depends on the intensity of sweating.

Athletes who sweat heavily and see white salt marks on their clothing are advised to add sodium during long workouts in the heat: isotonic drinks, salt tablets or salty foods. This is especially important during starts lasting more than two hours.

Magnesium and potassium supplements are popular among athletes, but taking potassium without monitoring tests is risky: excess potassium is dangerous for the heart, especially in people with kidney damage or those taking certain blood pressure drugs. A normal diet with vegetables, fruit, legumes and dairy products usually provides the requirement.

Quinine was once widely prescribed for night cramps. However, because of the risk of severe reactions - thrombocytopenia, arrhythmias, allergy - the FDA does not recommend it for treating leg cramps, and the American Academy of Neurology advises avoiding routine use. Tonic drinks with quinine contain a much smaller amount of the substance and are not a therapeutic agent.

Diagnosis: which examinations may be needed

A diagnosis of exercise-associated cramps is made clinically: from a description of the situation, the localization and the connection with training. If the episodes are typical, rare and pass quickly, special tests are usually not needed.

When cramps are frequent, occur at rest, in several muscle groups or are combined with weakness, the doctor looks for secondary causes. The basic set of examinations usually covers a complete blood count, electrolytes (sodium, potassium, calcium, magnesium), glucose, creatinine and indicators of kidney function, TSH, and also creatine kinase.

Creatine kinase should be tested no sooner than a few days after a hard workout: intense exertion itself raises its level, and the result may be misleading. During the examination it is important to honestly inform the doctor about all medications and supplements - diuretics, statins, stimulants, beta-agonists.

If a neurological cause is suspected, a consultation with a neurologist, electroneuromyography and, in some cases, genetic tests for metabolic myopathies are ordered. If the cramps are combined with pain in the calf while walking and disappear at rest, the doctor may check the vessels of the legs.

When to see a doctor

Some symptoms require immediate medical care. The editorial team highlights red flags for which it is not worth waiting and hoping that everything passes on its own.

• darkening of the urine (the color of tea or cola), severe pain and swelling of the muscles - possible rhabdomyolysis;
• cramps together with confusion, nausea, headache during a long start - possible hyponatremia;
• cramps with interruptions in the work of the heart, dizziness, fainting;
• cramps that arose after starting diuretics, beta-agonists or other drugs;
• cramps with progressive weakness, numbness or muscle atrophy.

It is worth making a planned visit to a family doctor or sports physician if cramps occur more often than once a week, interfere with sleep, appear during light activity or are not related to obvious overexertion.

During the visit it is useful to have a diary: when the cramp occurred, which muscle, what training preceded it, how much you drank, what you ate, which drugs or supplements you took. This significantly speeds up the search for the cause.

If the cramps are related to a prescription drug prescribed by a doctor, do not stop it on your own. The doctor may change the dose, replace the agent or adjust the electrolyte balance.

Editorial conclusions

During a cramp, passive stretching works best. For prevention the most important things are gradual preparation, a realistic starting pace, sleep and sensible nutrition; fluid and sodium are needed primarily in the heat and during prolonged work.

Magnesium, potassium and quinine are not universal remedies: the first two make sense with a confirmed deficiency, while quinine, because of its risks, is not recommended for treating cramps.

Frequent, atypical cramps or those associated with darkening of the urine require examination, and some - emergency care.

To understand the topic more deeply, read our articles on the causes of cramps and their connection with pharmacology, on rhabdomyolysis and on proper hydration during training.

References

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