Water vs Electrolytes

Qu: I train for about an hour each day and my friend said to make sure I get enough electrolytes and to have a powerade during my workout. I'm not running triathlons or anything like that, so is this really necessary?

A: No, not usually necessary for exercise 60 minutes or under, for us normal exercisers and definitely not for those exercising for weight loss.

There are 3 components to sports drinks:

· * Water for replacement of lost fluids

· * Electrolytes to replenish those lost in heavy exercise, to assist in retaining ingested fluids easier, and stimulate thirst

· * Carbohydrate for optimal absorption of fluids and to replace glucose lost in exercise

Exercise lasting 60 minutes or less is usually followed by a meal at some point, this meal typically contains carbohydrate and sodium. This, combined with stored glycogen, body electrolyte levels and water consumed during the exercise session will provide enough replenishment from exercise of that duration.

We all train pretty hard at the gym right?  But lets not confuse that with the intensity that an athlete would train at.

Higher intensity training and longer durations require rapid effective fluid, carbohydrate and electrolyte replacement to avoid dehydration, ˜hitting the wall and minimize the health risks associated with low electrolytes.

A general fluid guide is 200-300ml every 15-20 minutes, and athletes should pre-hydrate from the evening prior to the event.  The morning of the event it is advised to get in around 300-600ml with the pre-event meal, and then another 300ml prior to event.  Of course making sure there is time for an adequate toilet stop first. CHO requirements are around 30-60g per hour, which is what sports drinks provide.

Specially formulated sports drinks (like Powerade) have a particular level of carbohydrate and sodium which has been researched and proven as the optimum level. Sports drinks containing <8% of CHO allows water to be absorbed from the intestine rapidly any thing over this amount and rate of absorption slows. Sodium is typically between 200-600mg per litre and this stimulates the absorption of carbohydrate and water and retention of water. Sodium also stimulates thirst, and some athletes need this mechanism to ensure they get enough fluid in.

Other drinks like fruit juice, sports water, energy drinks, cordial etc may not contain the correct amounts of CHO or sodium and some contain caffeine which is dehydrating, so these aren't always effective for athletes. The inclusion of vitamins in water makes no difference to athletes or normal exercisers.

Just make sure you're consuming around 750 - 1000ml of water for your hour of exercise and keep a note of excessive fluid losses, which you can guage by how much you've sweated and whether that fluid loss resulted in a 1-2kg loss on the scale during the exercise session, in spite of drinking fluids.

Stacey
17 May 10