A triathlete’s guide to salt levels

A common concern of many triathletes when they start training and racing longer distances is whether they should increase their salt intake to replenish levels lost. Andy Blow explains all…

Even the healthiest diets will contain a reasonable amount of salt (sodium chloride), as it’s in virtually all foods to a certain extent. Salt is essential for life, and if you were deficient in it you’d probably develop symptoms such as fatigue, low blood pressure and, more than likely, would be craving salt intake, as the body seeks to correct the imbalance.

Salt excretion in sweat can vary dramatically from person to person, with some losing as little as 200mg/ltr per hour and others 1,700mg/ltr. If you’re training regularly without issues and not making an effort to replace additional salt, it’s likely that your losses would be quite low.

That said, if you do occasionally suffer with cramps, it might be worth experimenting with some supplemental salt (or electrolyte drinks) during times when this is likely to occur, to see if it helps. Taking in a little additional salt around heavy training and racing periods is not usually an issue for healthy athletes, but it helps ensure sweat losses are replaced properly and any small excesses will be excreted in the urine.

The links between high dietary salt intakes and poor health are unclear and not well understood, as there are many populations around the world who have incredibly high salt intakes but low incidences of cardiovascular disease. Although some prominent thinkers in medicine and nutrition are starting to point the finger at the combination of high levels of salt, fat and refined carbohydrates, which proliferate modern diets, as a dangerous combination, rather than at any one component in isolation, as has often been the case.

In summary, it may be worth trying to supplement with a small amount of salt or electrolyte drinks during times when training or racing hard, in hot weather or for long periods when sweat losses are high. Only then will you be able to evaluate if it is having a positive effect on your performance.

(Main image: Delly Carr)

Andy Blow Sports scientist

About

Andy Blow is a sports scientist with a degree in sports and exercise science from the University of Bath. An expert in sweat, dehydration and cramping, Andy previously worked as the team sports scientist for the Benetton and Renault Formula 1 teams, and remains an adviser to the Porsche Human Performance Centre. He specialises in electrolyte replenishment and founded the company he now runs, Precision Hydration. An elite-level triathlete in his younger days, Andy has finished in the top-10 of Ironman and Ironman 70.3 races, as well as winning an Xterra world title. Andy has also worked alongside Dr Raj Jutley, as well as other top sports scientists, to co-author a number of studies and books which have been published in BMJ Journals, the Journal of the International Society of Sports Nutrition and the Journal of the Endocrine Society.