Skeletal muscle spasms associated with exercise (EAMC) appear during or just after exercise. The etiology of EAMC development is not fully understood, and this topic is still subject to constant discussions. There are many reasons for the development of EAMC, the most common among sportsmen and health care professionals is the theory of dehydration and electrolyte imbalance.
- The influence of electrolytes
- Pickle juice as a way to spit
Depletion of fluids and electrolytes causes increased sensitivity of nerve endings. They increase the mechanical pressure on selected nerve endings, consequently developing contraction. It is estimated that during training fluid loss can range from 0.3 l / h to even 2.4 l / h. The standard amount of fluids that most athletes use during training is 0.4 to 0.8 l / h. It should be remembered that the portions of liquids should be adjusted individually to the environmental conditions, the rate of perspiration, the type of discipline being practiced, as well as the length and intensity of the training performed. In the case of training lasting up to an hour, water should compensate for fluid losses, and if the training is longer, in a hot environment or with high intensity – one should reach for isotonic drinks.
The influence of electrolytes
During prolonged physical activity the body loses water through sweat, urine and respiratory system. The total amount of water lost depends on the sex, body weight, level of physical activity, clothing and environmental conditions (temperature, humidity). Along with this, we lose valuable electrolytes such as sodium (Na), chlorine (Cl), potassium (K), magnesium (Mg) and calcium (Ca). The most attention should be paid to sodium (Na) and chlorine (Cl), because they constitute about 90% of the electrolytes lost with sweat. In a liter of sweat there is about 2-4 g of salt, so during a marathon run you can lose about 6 g of salt, and even more!
Sodium is one of the main electrolytes in the body fluid. The body needs it to maintain balance in the normal balance of body fluids and blood pressure. In combination with several other electrolytes, it is crucial for generating nerve impulses and muscle contraction. Because sodium plays an important role in the regulation of blood pressure and the balance of fluids and electrolytes, our body has an effective mechanism to help regulate blood sodium levels, depending on sodium intake. If the blood sodium level drops, a series of complex events leads to the secretion of a hormone called aldosterone, which activates the kidneys to maintain sodium. Another anti-diuretic hormone (ADH) also helps maintain normal sodium levels in body fluids by activating the kidneys to maintain water and sodium. Normally levels of aldosterone and ADH increase during exercise, which helps to save water and sodium in the body.
Although muscle spasms appear in a state of sodium deficiency, some researchers believe that changes are not synonymous with a deficit of the element. Nevertheless, it is important that active people and athletes take enough sodium to supplement lost resources with sweat. Despite earlier regulatory mechanisms, athletes may be exposed to muscle spasms and other problems due to low sodium intake. The reason is most likely the fact that they ignore “salty thirst” – they eat mostly unprocessed and unsweetened foods – and at the same time lose a large amount of sodium by sweating. The demand for sodium depends on the rate of perspiration; in every liter of sweat we lose 2-4 g of sodium.
The leadership of the body is a common phenomenon among active people. Intake of fluids exceeding their loss with sweat, urine and substitution of low-sodium drinks results in hyponatremia (<135 mmol / l). Recreational athletes are more exposed to guidance than people professionally practicing sports – due to lower physical activity and less fluid loss from sweat and women – due to lower body weight (low sweating index). Signs of conduction (130 mmol / l) are weight gain and headache.
Potassium is the main electrolyte found in all body cells, including muscle and nerve cells. It works in close connection with sodium and chloride. It is involved in the production of electrical impulses in the nerves and muscles, including the heart muscle. It occurs in most food products, but its special source is fresh vegetables, potatoes, some fruits (melon, bananas, berries, citrus fruits), milk, meat and fish.
In cases of low levels of potassium in the blood, or hypokalemia, muscle cramps and weakening of the myocardium may occur, or even cardiac arrest caused by impairment in the production of nerve impulses. Similarly, high levels of potassium in the blood or hyperkalaemia may occur in people who take potassium supplements and significantly exceed the recommended daily intake. High levels of potassium in the blood can cause electrical impulses and cause cardiac arrhythmia. The daily recommendations are 4,700 milligrams in adults.
Magnesium plays an important role in stabilizing adenosine triphosphate (ATP), a source of energy for muscle contraction, and also serves as an electrolyte in body fluids. Low magnesium intake is rare, possible for people who are limiting the intake of calories or consuming products from processed foods. Magnesium deficiency is responsible very little for the development of muscle contractions.
Calcium is responsible for building the skeleton, nerve conduction and muscle contraction. With calcium deficiency, calcium reserves in the bones are released , which leads to disturbances in their structure and increased susceptibility to fractures and injuries. Demand for calcium for an adult is 1000 mg. This element is found in various foods and beverages, including yoghurts, milk, rennet cheese, broccoli, spinach, kale, sunflower seeds.
Pickle juice as a way to spit
Taking small amounts of pickle juice can treat EAMC. This juice contains a large amount of salt and acetic acid, which triggers a reflex increasing the inhibition of neurotransmitter activity in skeletal muscles. It was indicated that drinking juice reduced the EAMC within 30-35 seconds and restored the electrolyte balance. In the Miller et al. Study, the effects of 1 ml / kg of body weight were compared to the water itself. The results indicated that contractions were shorter after ingesting the juice. Comparing these two conditions, no significant differences in plasma composition were found for 5 minutes after ingestion. The authors report that the amount of cucumber juice consumed had a slight effect on the extracellular concentration of electrolytes and hypothetically stated that it was associated with a reduction in the duration of contraction, which they associated with the suppression of nasal secretion through the mucosa.This, in consequence, reduces the activity of the motor neuron in the entire my body.
It seems unlikely that sodium or magnesium supplementation will effectively solve the problem of the emergence of EAMC. However, it seems reasonable to encourage athletes and physically active people to adhere to the recommendations for supplementing hydration and electrolytes to prevent diseases related to overheating the body. Therefore, healthcare professionals should recommend fluid balancing during and after physical activity.
Miller KC, Exercise-Associated Muscle Causes, Treatment and Prevention, 2010.
Nelson NA, Narrative Review of Exercise-Associated Muscle Cramps Factors that Contribute to Neuromuscular Fatigue, 2016.
Larson-Meyer E., Learn the connection between diet and muscle cramping, 2013.
However, I am missing a clear conclusion in the summary, what about supplementation with calcium and potassium. Because analyzing the article, as well as the reaction of your body to the soda from potassium recently, I come to the conclusion that it is probably worth while exercising intensely, and drink coffee. Although I eat a lot of vegetables (including 3-4 ribbons of celery and a few bananas a week), only cheap and unreleased tablets with potassium allowed me to completely get rid of the night cramps.