It's easy to forget to drink water on cold, dark, rainy Melbourne days like the ones that we've been having over the last few weeks, but that doesn't make good hydration any less necessary. After all, we still lose sweat from central heating, and from exercise and we still drink coffee and alcohol which will send us to the bathroom.
The science of hydration often feels more like an art than a science, but I have found a relatively simple formula, adapted from Sports Medicine Australia, that will make sure you're drinking enough water — even if it's 2 degrees and you're not thirsty.
In Winter, your base daily intake should be 2L (500mL less than Summer). That amount (plus the small amount of water that we get from food) makes up for the water we lose as part of our metabolism. However, that 2-litre base line does NOT account for the activities in our daily lives which use-up water faster than the average metabolic rate. To make up for those further losses, you need to add to your baseline:
Add 200mL (1 glass) to your daily goal for every shot of coffee or standard drink of alcohol to replace the water lost in urination.
Add 200mL (1 glass) to your daily goal for every 30min of resistance exercise (e.g. weight lifting) to replace the water you lose in sweat.
Add 400mL (2 glasses) to your daily goal for every 30min of cardio exercise (e.g. running).
So, if you have a coffee in the morning, go for a 5km run before work, then have wine with your dinner, you need 2L + 200mL + 400mL + 200ML = 2.8L of water that day.
Nearly 3 litres of water sounds like a lot, but you can mix it up with some other drinks. Softdrinks DO NOT count towards your total, but pure fruit juice (no added sugar), sugar-free sports drinks, and warm Winter soups DO count.
For more information on dehydration, email me directly via the contact page. For specific information on an injury you have, or for treatment, contact one of my clinics directly. You can find that information here.
Subscribe below to receive weekly email updates on injury prevention and management tips.
Dr Mitch Clark