The amount of water each person should drink a day varies enormously. Everyone has different requirements. Variables such as climate, health and exercise need to be factored into water requirements and, even then, there’s no set amount. The important thing to remember is that when you’re thirsty, you’re already dehydrated.
What’s Right for You?
There are many factors to consider when deciding how much fluid is right for your body. Is it an exceptionally hot day? Are you planning on running a marathon that day? Do you sweat a lot? The recommended 8 glasses a day may be more than enough for some people and too little for others. It’s important to listen to your body.
Exercise and Water
Before you start any physical exercise, think about what you have drunk over the previous twelve hours. Drinks such as alcohol, coffee, tea, and carbonated drinks are diuretics, so if you partied too hard the night before, you need to ensure you are properly hydrated before you begin your exercise. The American Council of Fitness thinks that 600 mls (20 ounces) of water, two or three hours before exercising is sufficient and then another 250 mls (8 ounces) thirty minutes before you start, but it all depends on your present state of hydration.
Obviously, the amount of fluid needed varies considerably from person to person and the outside temperature is also an influence. Some people can lose up to a litre of fluid an hour if they are involved in physical exercise.
Signs of dehydration include heart palpitations, light-headedness, dry mouth and nausea. In severe cases, there may be mental confusion and the subject may even lose consciousness. If this occurs, then obviously seek medical help.
Remember, if you are thirsty, you are already dehydrated.