So, what *are* electrolytes?
Electrolytes are ions, or particles, found in the body, which carry an electrical charge and pass ‘messages’ from cell to cell controlling things like nerve impulses, muscle function, fluid balance and PH level. In the case of fluid balance think of electrolytes as pack leaders or pacers. Water basically follows them wherever they go, so if they’re not there water doesn’t know where to go and it hangs around in the blood plasma; a person can literally drown from the inside, this is called hyponatremia and happens particularly during endurance events when people drink too much water but don’t take in any electrolytes.
The function of electrolytes in the human body
Looking at muscle function, muscles need an electrical impulse to tell them to contract, electrolytes are used by muscles in this way. That’s why if you do an endurance event and don’t take in electrolytes you may suffer severe cramp including stomach cramps where peristalsis, or the movement of food/fluid through the gut, is impaired; the muscles are in a state of confusion, they’re not getting correct instructions!
The most common electrolyte imbalances in the body involve sodium and potassium but other key players for sports people in particular, are magnesium, calcium, phosphorus, sulfate and bicarbonate.
Electrolytes in running athletes
We get enough electrolytes from a healthy diet but when we take part in endurance sports, particularly in hot weather, we need to top up stores because sweating gets rid of electrolytes through the skin. You might notice you feel the need to urinate more frequently, that’s because the kidneys try to reduce the amount of fluid in the body in order to maintain the correct concentration of electrolytes, i.e. electrolytes are low so the body lowers the fluid level to suit – not a good situation for an athlete!
Hot weather running nutrition strategy
So what’s the solution (scuse pun)? During the run up to an endurance event, particularly if the weather will be hot, eat a wide range of nutrient-rich foods. In the couple of days preceding the event don’t drown your electrolytes by drinking masses of plain water, drink fresh juice and water, perhaps with a pinch of salt. Salt your food a little more than normal too. On race day plan to take in electrolytes in the form of isotonic drinks and/or solid food/gels little and often. With solid food take water so as not to overdo electrolytes and cause stomach problems (works both ways!) In very hot climes use saltsticks, one or two each hour. And importantly, practise all this in training to hone what works for you.
Knowing what electrolytes are and how to avoid imbalances in the body will stand you in good stead when preparing for an endurance event.