Will electrolytes help my running performance?

How electrolytes can make you a better runner:

While it is possible to run a half marathon on water alone, you would likely feel more powerful and feel more energized when you cross the finish line if you’ve been able to include electrolytes during your run.

Why do electrolytes help?

Our muscle cells are powered by glucose and when we exercise our liver and muscles are able to release stores of glucose, by breaking down something called glycogen, to sustain us for ~45-60 minutes of exercise. After this time we need to be taking on additional glucose to meet the demand of exercise. Carbohydrate requirements per hour will differ for each runner but a good starting point is 30g per hour. This is where using electrolytes can be useful.

What are electrolytes?

Electrolytes contain nutrition such as glucose, sodium, potassium, magnesium and calcium as well as water. Most electrolyte brands contain 12-15g of glucose per 250mls of electrolyte drink. So, if we use the example target of 30g carbohydrate per hour, 250mls of electrolyte every 30 minutes would meet the goal fuel needs for a runner aiming to complete a half marathon in 2 hours.

Losing electrolytes when running

During the process of sweating, we are losing electrolytes which when replaced can help combat feelings of fatigue and help prevent dehydration. Knowing your hydration goals as a runner is important. Most runners will need ~300-500mls fluid per hour of exercise.

Sweat rates vary between individuals but will also be different if you are running in warmer versus cooler climates and will differ depending on your exercise effort. You can work out your individual sweat rate by using the following experiment:

How to know how much you lose?

Weigh yourself right before and after your run. The difference in weight is an estimate of the amount of fluid you have lost. If you are hydrating during your session and notice very little difference in weight immediately pre and post run, it means you have nailed your hydration goal! When replacing sweat loss post training you want to aim for 1.5 times the amount of weight lost, so for example if you lost 500g then aim for 750mls of additional fluid as a part of your recovery nutrition.