Microsoft word - hydration.doc
By Martin Mackay, Level 1 Assistant Coach
FLUID – CAN’T GET ENOUGH
Research at the Australian Institute of Sport found that very few athletes manage to fully replace
sweat lost during exercise. Investigating the drinking habits of many athletes – e.g. swimmers, rowers and runners – in training and competition, researchers found that athletes replaced 35-75% of their
Such a mismatch between fluid intake and sweat losses during exercise results in dehydration … the number one enemy of any athlete or person wishing an on-the-go lifestyle.
Exercise performance has been shown to decrease as the athlete becomes progressively dehydrated.
What it means is that you commence every subsequent training session with fluid debt.
Extreme levels of dehydration are potentially life threatening. The following hints help athletes and
coaches overcome potential barriers in achieving an adequate fluid intake and keep pace with sweat losses caused by training and competition.
HINTS FOR INCREASING FLUID INTAKE
Do not rely on thirst as an indicator of your fluid need
Thirst is a very poor indicator of fluid needs – particularly for young athletes.
Monitor the colour of your urine and how often you visit the bathroom throughout the day, as an
indicator of daily fluid needs. The clearer the urine in colour, the better hydrated you are – with dark
urine indicating a negative fluid balance.
I am not suggesting you stick your head down the dunny every time you go to the toilet … but have a
look. Aim to maintain a clear urine colour during the day and throughout training and competition.
Headaches are another indicator of dehydration
If you are that stage then it is possibly too late to rehydrate to maintain effective training or
competition. Rest and rehydration is most appropriate. In other words … GO HOME
. Have drinks readily available so athletes have every chance to meet fluid losses
For example, it is best for swimmers to place a water bottle at the end of a pool – rowers in the boat
or with the support crew – aquafit on the side of the pool – runners in a runner’s bottle … rather than
rely on a drink fountain in the locker room or water at the end of the session.
Avoid drinking excess amounts of caffeine-containing drinks
These fluids have a moderate diuretic effect and result in fluid loss from the body. Especially avoid
these fluids in competition. They should be limited to four cups per day. Excess amounts may lead to
dehydration. Alcohol is another fluid with diuretic properties and should be avoided after exercise as it makes it harder to replace sweat loss during exercise.
It is important to note that these beverages cause urine to become clear and copious, giving false sense of true urine balance.
Develop good drinking practices in training so you automatically drink in
competition to cope with sweat losses
Do not leave your fluid intake to chance. Have a fluid strategy planned before commencing exercise.
As a general guide, fluid intake should be 150-250ml at regular intervals (every 15-20 minutes) during
exercise. Remember … TOO LATE IS TOO LATE
In certain sports – such as rowing or football – circumstances or rules prevent
This can be overcome by placing fluid in strategic positions, giving the athletes the opportunity to
drink. Pool swimmers have no excuse. Ocean swimmers will need support.
In hot conditions, sweat losses are commonly greater than the maximal amount
of fluid tolerated by the athletes
Sweat rates as high as 3.7 litres per hour are generated by elite marathon runners. Heavier people
At swimming carnivals in hot conditions, just sitting around waiting for your event, there will be high
fluid loss. Sweat rates approaching these levels make it impossible for athletes to replace sweat losses during exercise and highlights the importance of maximising fluid intake before exercise.
Drinking 500-1000ml per hour for 2-3 hours leading into the start of exercise will ensure you are well hydrated. You will feel bloated but this extra fluid will be utilised within the first 10 minutes of high
Weight loss in some sports is encouraged during exercise as a means of weight
This is likely to be a problem in weight classed sports such as boxing, horse racing and weight class
rowing. Weight loss by fluid denial should not be utilised in most sports as a guide to cardio-vascular
fitness. Weight lost during exercise simply is an indicator of sweat that has not been replaced. A kilogram of
weight loss during exercise is equal to a litre of fluid that has not been replaced. This can be a valuable tool, particularly in sports where sweat losses are not always obvious – such as swimming, aqua-running and cycling.
Water is suitable for exercise lasting 60-90 minutes
However, fluids containing carbohydrate and electrolytes such as sport drinks, are perhaps the best choice during extended periods of exercise.
These fluids are designed to rapidly replace fluid and electrolytes (sodium and potassium) lost in
sweat. These fluids will help avoid the onset of cramps. In addition, sports drinks provide a valuable source of carbohydrate during exercise and competition.
Coaches should schedule regular drink breaks into training sessions to ensure the
athletes have adequate opportunity to keep pace with sweat losses
In warmer conditions, drink breaks may be needed every 10 or 15 minutes so athletes minimise fluid losses. Swimmers and aqua runners should have a sip every break of intensity.
The coach, a parent or a designated athlete may be rostered to organise water for the entire squad.
Remember, if it is a 50-metre sprint or a marathon … TOO LATE IS TOO LATE
… and you will not
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