Our internal body balances varies with age and gender. About 45% to 50% of body weight in females is water. Since males generally have higher amounts of lean mass, body water is around 50% to 60%.When normal conditions exist in the body, we have many mechanisms to help preserve our fluid and electrolyte balance. If these mechanisms fail due to illness, stress, exercise, climate variations, supplements, foods, or alcoholic drinks without adequate rehydration, imbalances may occur.
Symptoms of dehydration include:
- dry skin
- fatigue and weakness
- increased body temperature
- muscle cramping
- darker-coloured urine
- dry mucous membranes (mouth, nose, eyes)
Severe dehydration can also include:
- muscle spasms
- dark urine
- vision problems
- loss of consciousness
- kidney and liver failure
Water allows nutrients to be transported from the blood to the cells and the return of metabolic by-products (waste) to the blood to then be excreted out of the body. So many metabolic reactions in the human body rely on water as a medium.
When might we need to increase our water intake:
With exercise – During exercise, we need more water due to the fact that our and increased rate of muscle contraction and metabolism requires a larger delivery of nutrients and oxygen along with faster waste and heat removal from the body.
Growth and development – During growth and development, the percentage of body weight that is water and the percentage of water outside and inside of cells do not remain constant. When expressed as a percentage of body weight, body water decreases during gestation and early childhood, attaining adult levels by around 3 years of age.
Where should we get our water intake from?
Water intake doesn’t come only from drinking water. It also comes from tea, coffee, non-dairy milks, milks, and water from solid foods (mainly salads, cucumber and fresh fruits and vegetables). With thirst as a guide, humans are generally well hydrated. There is extreme variability in water needs based on climate and physical activity levels.
- Be aware of thirst cues.
- If no fluids are going to be given during exercise, you can pre-hydrate with the following regimen:
- 500 ml of fluid on the night before exercise
- 500 ml in the morning
- 500 to 1000 ml, 1 hour before exercise
- 250 to 500ml, 20 minutes before exercise
- Consume nutrient dense foods/beverages after exercise to assist in the re-hydrating process.
- If you have a history of cramping and “salty sweat”, you should consider adding good quality rock or sea salt to foods/beverages after exercising (a quarter to one-half teaspoon).
- For every pound of sweat lost during exercise, rehydrate with 2 cups of fluid.
- Dark colored urine can be indicative of a low water reserve in the body. So make sure your urine is light-colored and clear.