This test analyses your hydration level and looks at whether you are drinking enough fluid. In a normal healthy adult, water makes up around 55% of body weight in women and 60% in men. Your body uses water for many functions including digestion, brain function, cushioning joints, carrying nutrients into cells, and removing wastes, supporting normal blood pressure, regulating body temperature, and maintaining electrolyte balance. Good hydration is key to optimising everyday physical and mental performance.
Water requirements are highly individual, and vary according to activity level, seasonal temperature (we all need to drink more in hot weather), pregnancy, health conditions, and medications. On average, most adults require at least 1.2-1.6l of water per day – which equates to 6-8 x 200ml glasses. This amount increases in warmer weather, and when doing strenuous activity. Around 20% of this total can come from foods like soup, fruit, and salad. While many experts include tea, coffee and soft drinks in the total fluid intake amount, these drinks often contain sugar or artificial sweeteners, and caffeine which has a diuretic effect. Drinking 6 cups of tea, coffee or soft drinks does not provide the same net water gain as 6 glasses of water.
It is especially important to hydrate before exercise to support muscle function, circulation, and overall performance. A small-scale study of male and female recreational athletes investigated this issue and found that drinking 600ml of water 45mins before a training session enabled the athletes to arrive for training adequately hydrated rather than mildly dehydrated.
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