What is a sports drink and when should you use one?

Different types of sports drinks explained

A lot of claims are made about sports drinks and not all of them are based on science

There’s a wealth of sports hydration products on the market – but what do they all do? Dr Kevin Currell, head of performance nutrition at the English Institute of Sport, looks at what cyclists should be drinking, and when.


I have to say I feel privileged; I’ve spent many years studying sports nutrition and did a PhD researching in the area of sports drinks, so I should be well placed, as a triathlete and expert, to know which are really going to make a difference, and which products will be a damp squib.

Yet despite this I see adverts for all the various sports drinks available and get drawn into the marketing hype. Sometimes I have to stop, take a deep breath and remind myself of the science that I know so well.

I can only imagine that for someone without an in-depth knowledge of the science, looking at the range of sports drinks available must be confusing. So let’s take a look at some of the different sports drinks on the market and the science behind them.

Protein shake

What it does: These tend to only contain protein, with maybe a small amount of carbohydrate, plus other vitamins and minerals. There’s reams of scientific research showing that consuming protein after training will increase something called muscle protein synthesis. This simply means the body is building the muscle. Consuming protein after training helps the body repair muscles and promote adaptation (where muscles are repaired to become more suited to their use).

How to use it: Protein shakes provide you with lots of flexibility, you get good protein and you can then control your carbohydrate intake. Mix with lots of berries in a blender to make a good post-exercise recovery shake.

Recovery shake

What it does: These tend to contain a mixture of carbohydrate and protein, with some vitamins and minerals, depending on the product. They tend to have a composition very similar to milk. Eating or drinking carbohydrate and protein immediately after training will enhance the restoration of muscle glycogen – your primary energy store in training.

How to use it: These are great convenience products; if you finish a training session and you need to recover quickly then they are ideal. So if you have a long drive home, drink a recovery drink immediately after training to start the recovery process as quickly as possible.

Electrolyte drink

What it does: These tend to come in tablet form, although there are some that come as powders or ready to drink. They contain mixtures of essential electrolytes such as sodium, potassium and magnesium, all of which have key roles in the body. Research clearly shows that if you increase your electrolyte intake, particularly sodium, after a training session, it will lead to better rehydration. They work by ensuring the fluid you drink in actually stays in the body and doesn’t pass straight through you.

How to use it: Use electrolyte drinks after training, especially during spells of hot weather, when you need to rehydrate. Also great to sip on in the days leading up to a race to make sure you’re hydrated.

Carb sport drink

What it does: These are probably the most researched sports nutrition products. They contain carbohydrate in the form of sugars and electrolytes. The first research evidence suggesting that sugars can enhance endurance performance was in the 1920s during the Boston marathon, with a boom in research (and products) in the 80s and 90s. The most effective combination of sugars is that which combines maltodextrins (or glucose) with fructose.

How to use it: Use these during training to maintain the intensity of the training session.

4:1 sports drink

What it does: Most of these type of drinks claim that carbohydrate and protein in a 4:1 ratio is the “optimal ratio” to enhance performance and recovery. I’m not convinced that the research is there to fully support this, but what these drinks will do is improve your recovery from training, leaving you fit and ready for any subsequent sessions you may have planned.

How to use it: Drink this during training if you know you’re going to do another session later in the day.