Many people are unaware of the affects that dehydration can have on your body. When we exercise, our body has the potential to lose over one litre of fluid an hour, depending on how long and hard the exercise regime.
Failure to keep your fluid levels topped up during exercise can lead to dehydration which in turn affects your ability to exercise. It is therefore important to keep your fluid levels regularly topped up before, during and after exercise.
Take a look below at Newitts' guide to keeping hydrated during exercise.
Before you start
Before you begin exercising, it's important to have prepared your body for what lies ahead. This means drinking plenty of fluid before you begin. If you start exercising and you are dehydrated, your core temperature will rise faster which means your heart will have to work harder than usual. This can have a negative effect on your overall performance, or worse still, could lead to more serious conditions such as heat stroke.
The urine test
Providing you have drunk plenty throughout the day, and you've had at least an 8-12 hour break from previous exercise, your body should be prepared to cope with exercise at any time. If you're not sure how hydrated you are, you can tell by testing the colour of your urine. A hydrated person will have pale yellow urine, whilst darker urine symbolises dehydration. If you think you're dehydrated, start to drink fluids slowly at least four hours before exercise - as a guide you should be thinking about an intake of at least 500 millilitres in the 2 hours prior to exercise.
Fluid intake during exercise
The amount you need to drink during exercise will depend on how much you sweat and the length of time you are exercising for. One way to work this out is to weigh yourself before and after exercise. Take into account your urine - it's better to weigh yourself before you urinate at the start of exercise and after you have urinated at the end of exercise to get the most accurate result. In general, it is advised that for every kilogram that is lost, you replace this with around 1.5 litres of fluid.
What to drink
If you're planning to exercise for less than one hour, water is all your body requires to keep hydrated. However, if you're exercising for longer than this, your body will benefit from a sports drink that contains carbohydrate, or even just a sugary drink (such as squash) to keep your glucose levels up and provide your body with extra fuel. If you're training for a longer event, you'll need to train your body to drink on the go. Practising drinking while exercising will help you to ascertain exactly how much your body requires. Never wait until you feel thirsty to drink - at this point you are already dehydrated.
Drinking after exercise
Drinking after you finish exercising is highly important for restoring some of your body's fluid levels and helping your body's muscles to recover. Sports drinks or water are the best options, while it's important to avoid alcohol or caffeinated drinks straight after exercise because they are diuretics, meaning they remove water from your body quicker by increasing the amount of fluid your kidneys produce.
Symptoms of Dehydration
There are various signs of dehydration which can occur during or following exercise such as muscle cramps, dizziness and fatigue. One of the most common signs is a dry mouth, so if you start to feel parched, reach for the water bottle. Feeling light-headed can also be a sign of dehydration, and your body's way of telling you to slow things down a bit. More serious symptoms of dehydration include heart palpitations (when it feels like your heart is jumping or pounding), confusion, sluggishness or fainting. If you experience any of these symptoms, stop exercising right away and take small, frequent sips of fluid until you start to feel better. If things don't improve, consult your doctor.
It's important to be aware of overhydration as too much water in our bodies can lead to hyponatremia, a condition caused by excess water in the body diluting the sodium content in our blood. This condition is normally caused by long duration exercise or when a person drinks fluid faster than their body is actually losing fluid.