#22 WATER

It’s crucial to our very existence, but how much do you understand about our need for H 2 O

Water is often overlooked and, as such, it’s all too easy to underestimate the importance of hydration. Water plays an absolutely integral role in our ability to not only function but also live. So when it comes to any sort of activity that makes us sweat a lot – such as cycling, for instance – it’s important to appreciate how much water we’re losing and how much we can actually afford to lose.

How much water loss is a problem?

A two per cent reduction in bodyweight due to water loss is all it takes to have a detrimental effect on performance. So if you weigh 75kg and over the course of a long ride exhale and sweat out 1.5kg of the water contained in your body, your performance will drop off a cliff. It may sound like a lot, but if you don’t replace the fluid you’re losing, it’s easily done – especially on extended turbo sessions and warmweather rides.

What if I lose more than that?

Lose more than two per cent and it throws out your electrolyte balance. Your muscles may start to cramp up and you might feel weak, lethargic, nauseous, bloated or confused. A headache, slurred speech, or swollen hands and feet during or after exercise can also be symptoms of dehydration and hyponatremia (severe loss of electrolytes).

How can I work out how much I lose?

Do a basic sweat rate test. A turbo works well for this as it enables you to ride in a controlled environment.

• First off weigh yourself

naked before the ride • Take a controlled amount of water, say 500ml, and ensure you drink all of it over the duration of your ride (also take a note of the weights of any food or gel you consume) • After the ride strip down, dry

off and weigh yourself again

Using your before and after weights you can work out your sweat rate for the duration, temperature and effort level of that ride. So if you weighed 75kg before a one-hour ride and 73kg after, but also had 1x 500ml water during, then you lose 1.5kgs of water an hour.

With this number you can more accurately control your hydration levels and use it to guide your hydration strategy.