Hydration for Health and Performance

The human body can be broken down into two basic compartments – lean mass (i.e.. muscle, bone, tissue) and fat mass (i.e. essential fat in the brain, bone marrow, organs and storage fat).

• Lean mass is approximately 73% water
• A 1 to 2% dehydration level will not make you thirsty, but will negatively affect your physical and mental performance (i.e. poor stamina, poor concentration)
• The body can last up to six weeks without food, but it can last only one week without water

Water is essential to good health

• Water is a key component of blood, which carries nutrients and oxygen to all the cells of the body
• Water is a key medium for the body to remove waste products
• Water is used in many metabolic functions (i.e. energy production)
• Water is a vital component of tissue that helps protect the organs, joints, muscles etc
• Water is the lubricant for the brain and joints
• Water is vital in regulating body temperature
• Water helps to maintain skin health and appearance

How much water should you drink each day?

The answer depends on your body size and daily activity level. On average an adult will lose between 1 to 3 litres of water per day. Water is lost through urine and faeces, sweat and breathing.

This deficit is made up from moisture in the food that we eat and beverages we might drink. Some beverages like coffee or beer contain substances that cause a diuretic effect (i.e. caffeine, alcohol). These do not help to replace lost water. Therefore as a general rule of thumb it is a good idea to drink at least 2 litres of water each day in addition to other beverages.

This may seem like a lot at first, but over a few weeks your body alters its hormone levels and drinking the water will become easy. If you are exercising regularly you may need to drink more water to match your losses (i.e. increased sweating).

Dehydration

Dehydration occurs when the water content of the body is too low. This is easily fixed by increasing fluid intake. Symptoms of dehydration include headaches, lethargy, mood changes and slow responses, dry nasal passages, dry or cracked lips, dark-coloured urine, weakness, tiredness, confusion and hallucinations.

If you regularly don’t drink enough water there can be an increased risk of kidney stones and in women urinary tract infections. There is also limited evidence to suggest an increased risk of some cancers including bladder and colon.

Ways to incorporate water into your daily schedule

• Buy a bottle of water where you know the volume. That way it is easy to calculate how much water you have consumed throughout the day
• Buy a water bottle that comes with a sports cap so you can take it with you to any activity
• Half fill a water bottle and freeze it overnight. When you take it with you the next day, you can top it up and have cold water for several hours
• Have a 2 litre jug of water in the refrigerator and finish it by the end of each day
• When dining out, ask for a jug of water for the table
• Replace some of the coffee and tea you might normally drink during the day with a glass of water. Aim for no more than 4 caffeine containing drinks per day
• Form the habit of having water with lunch and dinner
• Add a slice of lemon or orange to water to give it a hint of flavour
• Using sports water is fine, but be careful, some of them are quite high in calories and they can be an expensive way of replacing your lost fluid
• Discuss your program with a doctor if you have high risk factors, or a known problem with your heart

Stay Cool This Summer – How to Avoid Heat Illness

Despite what has been an unseasonably mild summer to date, the hotter days are becoming more frequent and it is important to be aware of the dangers of exercising during this time of year. Summer climates increase the risk of developing heat illnesses such as heat stroke when exercising, resulting in many debilitating health complications such as:

• Feelings of tiredness, weakness, dizziness and faintness
• Dehydration and headaches
• Excessive fatigue
• Heat cramps

So what can you do to help yourself avoid these possible side effects?

Pre-exercise

• Hydrate effectively – Daily water requirements during summer increase to a minimum of 4L per day
• Drink 2-3 cups of water 2 hours before and 1 cup 10-15min before undertaking exercise
• Avoid hot foods, alcohol and heavy foods that increase your core temperature
• Choose lightweight, light-colored and loose-fitting clothing as well as wearing a hat
• Use sun block with an SPF rating of 15+ or higher

During exercise

• Avoid exercise during the hottest time of day; train closer to sunrise or sunset
• Drink 1 cup of water every 15minutes throughout exercise
• If you feel any headaches, fatigue or irritability or notice your exercise performance decreasing, stop exercising and cool off

Post-exercise

• Weigh yourself before and after exercise and replace any lost fluids accordingly
• Drink 1.5L of water for every kilogram of fluid you lost during exercise
• Try to avoid too much sports drink, however for intense exercise above 60min, these may help to further accelerate water intake after exercise in the heat

Remember: Planning ahead for exercise in the heat will assist you in avoiding the health complications associated with heat illness this summer.

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