The importance of water for exercise

Written by William Fryer - MA Oxon

It is one of those facts you can roll out to your five year old that is sure to amaze, “The body is mostly made up of water, between two thirds and three quarters water in fact.” This of course is why it is so important to remain well hydrated throughout the day and as you exercise. For many people their little niggles and aches can often come down to a form of tiredness and dehydration. It is everywhere, in the news, on the radio, across the internet, throughout TV and in magazines that we should drink more water.

Why do we fail to keep hydrated?

While most know that exercise and proper hydration go hand in hand, many fail to realise the correct way of keeping hydrated while exercising. There have been studies conducted that shows that even high performance sports stars and athletes fail to keep properly hydrated. At a level where every performance increase and decrease counts, this has a big effect, but for someone who is simply exercising for health reasons the difference between being properly hydrated when you exercise and not could mean the difference between you sticking with your health regime or you finding it incredibly tough.

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The science part of it does not need much explaining, most people realise that pretty much every function in our body comes down to water. We need it for our cells to operate, for our blood to pump, for our muscles to regenerate. One of the biggest failings people have is that they begin their exercise already dehydrated. The difficulty in getting going with exercise could be due to a lack of water from the second you begin your exercise. People need to increase their water intake an hour or two before exercising.

There is also debate over how people hydrate during exercise. The proactive style would have people drink little amounts of water, regularly, ensuring they are maintaining correct hydration. The reactive method is to drink as soon as you feel thirsty. The science seems to be pointing towards a reactive method being better, i.e. drinking when you are thirsty, however the failing is that many people do not properly recognise the symptoms of thirst. Many people go through their day in constant need of liquids without realising it. The solution is to mix both approaches, if you are thirsty then you drink, if you are not thirsty drink anyway because you probably need water while you are exercising it without realising.

The other element of the debate is what additives and special drinks people need. While sports drinks with electrolytes can be very important for high end athletes the reality for most of us is that plain, pure water is more than adequate. This is especially the case if we are only exercising for an hour or so. You may learn to recognise when your salt balance has become incorrect but for most people energy drinks are just adding unnecessary calories to their body. The final additive to look at is coffee. It has long been thought that coffee flushes liquid out of the body but the latest research shows coffee may actually have a benefit for exercise. One cup of coffee before your work out will add a little hydration, but it also has an effect on energy levels. The caffeine boost perks you up and gets adrenaline flowing and can give you a little extra during your work out, but you still need to ensure you keep drinking water.

The important thing to remember is that you probably need more water than you realise if you are exercising. In fact you probably need more water during your day no matter what. And if you feel you need to buy expensive energy mixes and drinks you are probably wasting your money if you are not a high performance sports person, plain water is more than good enough for most needs.