Sports drinks are an effective way to stay hydrated and fuelled while on the bike, but they also cost money for that ready made convenience. Sports nutritionist Dr Kevin Currell explains how to get the best of both worlds if your funds are tight.
Using a sports drink delays fatigue and enhances performance. But how does it do this? During prolonged exercise, fatigue or the ability to hold a set intensity occurs when blood glucose (or blood sugar) drops.
In studies, nearly all subjects who got tired showed a decrease in blood sugar. Drinking a sports drink delayed the drop in blood sugar and therefore delayed fatigue – but why is blood sugar so important? Sugar is the main fuel for the brain, and the body protects the brain at all costs, so a lack of it makes you slow down.
In hotter conditions, losses of more than 2% of body weight in fluid can weaken performance, so you must make sure you replace this. When you exercise without fluid ingestion your core temperature will rise and you’ll get tired. When you take in fluid your core temperature will still rise, just not as fast when you didn’t drink the fluid. So, you’ll delay the point at which you fatigue.
So, in summary, sports drinks delay fatigue and enhance performance by preventing a fall in blood sugar and minimising the effects of dehydration.
So what are the ingredients that do this? Simply sugar, salt and water. The sugar prevents a decrease in performance caused by a drop in blood sugar, the fluid helps stave off dehydration, and the salt helps absorb and retain the fluid.
Using table sugar
Making your own sports drinks will save you a fortune and there are two main ways to tackle this. These will make up 1 litre of sports drink. The first involves taking 60-80g of table sugar, adding half a teaspoon of table salt, adding no-added-sugar cordial and topping up with water.
If you add less than 60g of sugar it might not be enough to prevent the drop in blood glucose. If you add more than 80g of table sugar you’ll start to delay fluid absorption. This means the fluid takes longer to get to where it needs to be – the blood and the muscles – and will not be as effective at staving off dehydration. More than 80g of table sugar also increases the likelihood of stomach upsets, particularly if you are running soon afterwards.
Using fruit sugar
A second option is to use fruit juice. Again assuming you are making 1L of sports drink add 400-600ml of the fruit juice to a 1L bottle and dilute with water, adding half a teaspoon of table salt. The advantage of this method is the type of sugars found in fruit juice – mainly glucose and fructose – which are the most easily absorbed mixture of sugars. This will lead to more of the sugar being used as fuel, increased fluid absorption and give a better performance compared to a glucose-only drink.