by Rod Cedaro (M. App. Sc.)
Consultant Exercise Physiologist ACC Accredited Level III Triathlon Coach

Successfully competing in endurance sports such as triathlon – which is mostly completed in hot environments requires close attention to adequately fuelling and refuelling your body with appropriate fluids and foods consistently.

Rod Cedaro

Fluids: Stay Adequately Hydrated

As an endurance athlete, especially a triathlete who trains and competes in hot and humid weather conditions, your biggest potential problem is the constant risk of dehydration. This risk becomes greater the longer you train or compete and/or when you train more than once a day – which for most triathletes is commonplace.

Some points to consider:
• If you lose too much fluid in sweat without replacing what’s been lost (in both fluids and electrolytes like sodium and potassium), you risk becoming dehydrated, plain and simple. Research has shown that even partial dehydration (2% loss of body weight) can decrease performance significantly (e.g. By 2% even at this marginal rate of dehydration).

• The best way of battling this fluid loss is by using a “sports drink” (e.g. Gatorade) which will help by replacing both fluid and electrolytes. “Energy drinks” on the other hand (e.g. Red Bull) have the potential to do more harm than good.

• When you consider (even at an age-group level) that the difference between top finishers is often less than a minute, you can’t afford to lose time due to dehydration.

There’s a right and wrong way to hydrate:

You can “over-hydrate” so have a hydration plan in place before training and competing.

• Remain hydrated throughout the day, be sure to turn up to training/competitions well hydrated. If you start even partially dehydrated you’re already behind the 8 ball. Make sure you’re urinating clearly throughout the day BEFORE you start training/competing. To achieve this start the day by grabbing a sports drink, then using water bubblers, drinking fountains, office coolers, and other beverages/dispensers regularly throughout the day.

• Hydrate 2 to 3 hours before training and competitions. Aim for 2 cups (500ml) of fluid at this time and an additional 250ml 10 to 20 minutes before you start training/competing.

• Drink to replace sweat; don’t over-drink. In-experienced triathletes, particularly those who are a little slower in competition can have a tendency to drink too much and run the risk over-hydrating, which can lead to “hyponatremia” – particularly if they are drinking low sodium beverages like water or flat Coke. The easiest way to offset the chance of suffering from hyponatremia is by knowing how much fluid your body requires (see sweat rate chart below).

Knowing your sweat rate is pretty simple. To determine your fluid requirements simply monitor your sweat rates. These can vary for each person and for the same person depending on weather, exercise intensity of exercise, acclimatization status, etc.

So be sure to measure:

How much weight you lose during exercise (in mg) + How much fluid you consume during exercise (in ml) = The amount they SHOULD drink to replace sweat losses