What do Olympic athletes drink?

What do Olympic athletes drink?

Chemistry of the Olympics

What's in those sports drinks?

All the Olympic and Paralympic athletes will be reaching for the sports drinks this summer.

Dehydration causes tiredness during exercise. Sports drinks can help athletes to push themselves to their limits.

'The evidence for sports drinks is overwhelming,' says Mayur Ranchordas, senior lecturer in sports and exercise nutrition at Sheffield Hallam University, UK.

What is in sports drinks?


Tests found that cyclists performed better after rinsing a carbohydrate solution around the mouth before spitting it out, compared to rinsing with a sweetened drink containing no carbohydrate.

Cyclist drinking_77295139

Cyclists perform better if they drink a carbohydrate solution

Carbohydrate receptors in the mouth activate brain regions believed to be involved in reward and motor control, according to recent research.

Most sports drinks contain the carbohydrates glucose and fructose, which muscles use as a source of energy.


Most sports drinks also contain electrolytes, such as sodium and potassium, to replace those lost in sweat.

Electrolytes are charged ions which conduct electricity. In the body, sodium ions help to ensure that cells are hydrated.

Sweating athlete_119159941

Athletes lose electrolytes when they sweat

Sweat rates differ between athletes. 'You might have an athlete who loses 2-3kg of water but very little sodium or potassium, whereas another with only 1kg loss might actually have very concentrated sweat with high levels of sodium,' explains Ranchordas.

He and his team measure sweat rates of athletes by weighing them before and after exercise and measuring electrolyte concentration in the sweat. This knowledge has led to a range of different drinks, to suit different needs, being developed.

Additional extras

Some sports drinks also contain caffeine. 'We have found that adding caffeine to a carbohydrate drink will enhance skill as well as endurance,' says Ranchordas.

Athletes are allowed to use caffeine to improve performance. However, competing athletes need to be careful to avoid drinking sports drinks containing traces of banned substances.

'Contamination is quite a big issue and there are supplements out there that are contaminated,' Ranchordas says. He sends supplements for testing to make sure there is nothing that is banned in them.


Caffeine, found in tea and coffee, is added to some sports drinks

Athletes have to be careful of caffeinated products, which can also contain other banned substances such as ephedrine.

What else?

Not all sports drinks are created equal. Isotonic, hypotonic and hypertonic drinks all contain different amounts of carbohydrate and electrolytes.

'Different drinks do different things,' Ranchordas says. Isotonic sports drinks contain a 6-8% carbohydrate solution and help to transport fluids and carbohydrates into the bloodstream.

Hypotonic drinks have weaker carbohydrate solutions and less sodium.

Hypertonic drinks, which contain about 10% carbohydrates, are drunk after exercise to help muscles recover.

What should I drink after I exercise?

Sports drinks are highly acidic and can damage tooth enamel. For muscle recovery and rehydration post-exercise, Ranchordas recommends a pint of skimmed milk.

Drink milk_78630435

Milk is good to drink after exercise

'There is really good evidence that milk is great for recovery,' he says. Its combination of electrolytes, lactose and proteins make it the ideal tooth friendly alternative.

Edited from an article that first appeared on Chemistry World with kind permission of the Royal Society of Chemistry. View the original article on Chemistry World.

Curriculum information

  • Summary


    Curriculum key wordsOther web links
    • 5
    Science Curriculum Links
    National CurriculumCurriculum for excellenceNorthern Ireland Curriculum