I can’t count of the amount of times an athlete has asked me “Why do my calves keep cramping up?” The first thing I ask is if they are hydrated well. If they are well hydrated, we need to look a little harder. Following is a checklist that I’ve made for an athlete to do their own assessment to determine the cause and hopefully eliminate it.
Leg Cramps During Exercise
Leg cramps that occur randomly are usually caused by mineral deficiency, but those that occur specifically during exercise could also result from inadequate blood supply to the muscles due to vascular insufficiency. These cramps go away once you stop exercising, whereas cramps caused by mineral deficiencies typically don’t go away until you’ve replenished your body with adequate minerals. Especially during long endurance training and sporting events, it’s important to replenish with sports drinks, fruits or other snacks containing electrolytes.
Your body requires sodium to maintain normal fluid balance and regulate blood pressure. Sodium also works together with other electrolytes for muscle contraction and nervous system function. If you’re sodium deficient, your body will most likely tell you by causing you to crave salty foods. I tend to salt my meals with 1 gram of pink Himalayan salt. That equates to about 5 turns of the grinder. I find my muscles feel stronger and fuller when I have sodium on board. According to the UK Salt Association, “The presence of Sodium ions is essential for the contraction of muscles, including that largest and most important muscle, the heart. It is fundamental to the operation of signals to and from the brain. Without sufficient sodium your senses would be dulled and your nerves would not function.” (UK Salt Association, 2022). After sweating during prolonged endurance workouts, you lose a lot of sodium as well as water, so wash down your salted foods with plenty of water.
According to the National Institutes of Health (NIH, 2021), adults need 4,700 milligrams of potassium every day. Potassium is critical for proper nervous system and muscular function, which is why your muscles can cramp if you’re deficient. Consuming too much potassium by taking supplements that greatly exceed the recommended daily value of 4,700 milligrams, however, also poses a threat to your nervous system and even the muscular functioning of your heart. Since most foods contain potassium, you should be able to get enough if you’re consuming potassium-rich foods daily. Whole foods like fruits, vegetables, milk and fish are rich sources of potassium. Bananas, melons, citrus fruits and avocados are potassium-dense fruits, while potatoes, sweet potatoes and winter squash are your go-to veggies for potassium.
Calcium plays a crucial role in muscular contraction, including in your heart and blood vessels. It also plays a role in nerve impulse generation. If you’re calcium deficient, you may experience muscle cramps or impaired muscle contraction. According to Harvard Health Publishing (Harvard Medical School, 2022), the average adult needs about 1,000 milligrams of calcium daily. You can get 244 milligrams of calcium in a 200-milliliter glass of skimmed milk. The most calcium-rich vegetables are dark, leafy greens. Almonds, figs, yogurt and cheese are also good sources.
Magnesium is a mineral that stabilizes adenosine triphosphate, which is the energy source that fuels muscular contraction. Feeling weak, cramps and muscle twitches are signs of magnesium deficiency. Increase your intake by eating beans and legumes, nuts and seeds, whole grains, bananas and dark, leafy greens.
Irish Heart Foundation (2022) Let’s Strike Before Stroke. Available at: https://irishheart.ie/campaigns/strike-stroke/salt/ (Accessed 29 April 2022).
Harvard Health Publishing. Harvard Medical School. Staying Healthy. How much calcium do you really need? Available at: https://www.health.harvard.edu/staying-healthy/how-much-calcium-do-you-really-need (Accessed 29 April 2022).
National Institutes of Health, Office of Dietary Supplements (2021) Potassium, fact Sheet for Health Professionals. Available at: (https://ods.od.nih.gov/factsheets/Potassium-HealthProfessional/ (Accessed 29 April 2022).
Salt Association (2022), Salt & the Function of Our Cells. Available at: https://saltassociation.co.uk/education/salt-health/salt-function-cells/ (Accessed 29 April 2022).