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Keep Drinking (water)

Keep Drinking (water)

How much water do you drink a day? Is it enough?

It's quite surprising how much of an effect even a very low level of dehydration can have.  Being 2% below optimum can result in a 10-20% loss of performance; 5% can be 30%+; anything over 8% is life threatening, so it is something we should all take seriously. The easiest way is to check if you are hydrated enough is to look at the colour of your pee; it should be the colour of pale straw. Darker and you could be a little dehydrated, clear and you could be losing essential electrolytes (vitamins and minerals your body needs to function optimally).  Remember, this not just physical performance (indeed, the effect on maximal strength has had much more varied results when studied), the ability to focus, concentrate and general alertness are all affected.

A simple calculation to determine your basic level of fluid intake in litres (excluding fluid lost during exercise) is to take your bodyweight in kgs and multiply by 0.03 e.g. if you weigh 85kg your fluid intake should be roughly 2.55 litres.  During exercise keep sipping, I'd suggest a guideline of 300ml minimum per hour (anything over a litre is unlikely to be necessary though).

Finally, remember water isn’t the only way to keep hydrated; tea counts too, especially herbal teas (green tea has many health benefits in its own right, peppermint tea is good for soothing the digestive tract, chamomile is good for relaxation etc). Diluting juice counts as well (there are potential issues with sugar content but that's a separate discussion).  Although higher caffeinated drinks have a net positive effect on hydration unless they’re very strong, it is much simpler to discount these in terms of keeping you hydrated.

So keep drinking (water), it will help you in the gym, with focus through the day and going to the loo provides a good excuse to get up from that computer screen and stretch your legs for a couple of minutes.


Alex Ferentinos - https://www.facebook.com/nutritionandtrainingconsultant

Effects of dehydration on exercise performance - Barr SI (1999)

The influence of hydration on anaerobic performance: a review - Kraft JA et al  (2012)

Fluid balance and endurance exercise performance - Cheuvront SN ​et al ​(2003)

Ad libitum vs. restricted fluid replacement on hydration and performance of military tasks - Nolte HW ​et al ​(2013)