By Andrea du Plessis (RD).

Nutrition tips to avoid muscle cramps

One of the biggest fears of any runner is getting muscle cramps on race day. Step up your nutrition plan to make sure your muscles have sufficient levels of all the nutrients that could help prevent muscle cramps.


Did you know?

Leg cramps are not always caused by nutrient deficiencies. Exercise induced muscle cramps may occur due to decreased blood supply to the muscles, which is why the cramps stop when you stop running. Overtraining, or starting with a new exercise regime, may also result in muscle cramps during exercise. A biokineticist will help you to manage these factors to reduce muscle cramps.


Nutrition related causes of muscle cramps

An imbalance in, or a shortage of some nutrients may trigger or contribute to muscle cramps.

  • Magnesium and Calcium
    These two minerals work closely together in supporting muscle contraction. A deficiency in either of these may trigger or aggravate muscle cramps. During exercise, the body loses magnesium through sweat and urinary losses may also contribute to a magnesium deficiency. Most people do not consume sufficient levels of magnesium and calcium through their diets, which is why supplementation is recommended.
  • Sodium and Potassium
    These two nutrients are called electrolytes (or salts), which participate in energy and muscle metabolism during exercise. Sodium and potassium is lost through perspiration (that is why your sweat tastes salty), so supplementation before and during exercise is recommended.
  • Water
    Dehydration, or over-hydration during exercise is very likely to cause muscle cramps, notably because it is associated with an imbalance in electrolytes in the blood and muscles.

5 Calcium sources

Tinned fish, Dairy, Nuts, Seeds, Soya milk

6 Magnesium sources

Dark green leafy vegetables, Dark chocolate, Pumpkin seeds, Coconut, Avocado, Red meat

6 Sodium sources

Salt, Soy sauce, Feta cheese, Olives, Biltong, Pickled gherkins

6 Potassium sources

Guava, Celery, Tomato, Potato, Banana, Beans

Pre-exercise booster

This recipe is packed with magnesium, calcium and potassium – the ideal pre-run meal, to enjoy 60 minutes or longer before exercise.

RECIPE: Cashew-Cocoa-Coconut Booster
In a blender, combine 1 small banana, ¼ cup cashew nuts, 1 tablespoon desiccated coconut or coconut shavings, 1 heaped teaspoon cocoa powder (or Nomu Skinny Hot Chocolate powder) and 250 ml milk, to make a delicious smoothie. (or replace the milk with yoghurt for a thicker smoothie-bowl consistency)

In your race belt / pack

Calcium & magnesium tablets:
for events longer than 2 hours, take 200-400mg calcium and 100-200 mg magnesium after the first 2 hours.

Rehydrat Sport:
for events longer than 1 hour, take 1 sachet Rehydrat sport every hour, especially on hot days when you perspire a lot


Post-exercise recovery

Magnesium tablets:
100-200 mg magnesium taken immediately after exercise will help with recovery and prevent muscle cramps

Rehydrat Sport:
1 sachet immediately after exercise will help muscle recovery and may help prevent muscle cramps

RECIPE: Biltong, Avo & Rocket Recovery salad:
On a bed of rocket, place sliced biltong, sliced gherkins, pumpkin seeds, cocktail tomatoes and celery slices. Top with avocado slices, sprinkle with crumbled feta and drizzle with balsamic glaze for an extra punch of flavour and potassium.

Supplement Shopping List

Magnesium & calcium:
because they work so closely together, magnesium in combination with calcium is ideal

Potassium & sodium:
These electrolytes are found in combination in Rehydrat and Rehydrat Sport

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For any nutrition related questions, visit: Andrea’s Facebook Page

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