Originally published as a guest post on Team Grit OCR‘s blog

Many of us are walking around chronically dehydrated – but, did you know that a loss of as tiny as 2% in our weight in water can negatively impact physical performance? This can show up in the form of reduced endurance, increased fatigue, reduced motivation, and higher percieved effort.

Over time, dehydration can start to affect:

  • Mental cognition (i.e. short term memory and concentration)
  • Energy levels
  • Mood
  • Skeletal muscle (leading to cramps)
  • GI function (hello, constipation)
  • Skin health
  • Water balance (we all love bloating and water retention, don’t we?)
  • Kidney function
  • Cardiovascular function

Along with getting adequate sleep and proper nutrition, staying properly hydrated is one of the most basic (and simple!) things you can do to keep on top of your health and performance.

How much water should I be drinking?

There are some super general guidelines out there, but remember that water intake needs are INDIVIDUAL.

What we hear/read most often is 8 cups of water a day. This works okay as a general rule, but it doesn’t take into account the size of the person and their activity level.

As a starting point, I like to recommend you drink at least 30ml of water per kg of bodyweight per day. This is the bare minimum if you were sat in the office all day.

If you workout, you should be adding another 500ml per hour of exercise you’ve done.

Water intake should also increase if you’re consuming diuretics throughout the day – these include coffee/tea (yes, I know, sorry), juices, sodas, and alcohol (again, sorry). For every 100ml of diuretic consumed, follow up with another 50ml of plain water. 

i.e. if you have a cup of coffee, make sure you’re having at least a small cup of water along with it or immediately after!

You are a unique snowflake

How much water you need is unique to YOU and it’s dependent on a few factors:

  • Gender, age, and bodyweight
  • Your diet and the types of foods you eat (20% of our water intake comes from our food!)
  • Your activity level and exercise duration
  • Your environment and how acclimatized you are – for example, studies show that performance in hot climates is affected to a greater degree than performance in cold temperatures

Your urine is also a great indicator of whether or not you’re drinking enough. A lot of fitness Instagrammers joke about peeing clear all day and being #hydratedAF with their gallon water bottles, but you really don’t need to be at that level (over-hydration can be a real problem). Use the chart below as a guideline! Remember that diet, medication/supplement and alcohol intake can affect urine colour as well.

Source: Player Scout

You don’t necessarily have to be chugging water like there’s no tomorrow, but during the day it’s important to listen to your body and the signals it’s giving out. This may sound super basic, but if you’re thirsty then you probably need to drink. If you find your mood and energy start to dip, you’re getting irritable, and/or you feel a headache coming on, try getting some water in you and see if that helps. Often times hunger and thirst can feel similar – if you’re hungry at an odd time and haven’t drunk in a while, trying having some water and see if you’re still hungry 15 minutes later. If you’re no longer hungry, then you were probably just dehydrated.

If you’re training outside at high intensity for long hours, you’ll definitely need more water. Don’t wait until you’re parched to drink! Sip on water periodically throughout your session to keep your performance on point. Making sure that you’re well hydrated before training is crucial as well as the rate of dehydration during exercise occurs much faster.

If you want to nerd out on some numbers and figure out the exact amount of water you should be drinking during training, you can check out this calculator here, which takes into account how much water you’re losing through sweat.

Beyond just water

Time for a chemistry lesson!

Water is key, but athletes need to think about electrolytes as well in their hydration equation.

Training for long durations means you’re going to be sweating out electrolytes like sodium, potassium, magnesium, calcium and chloride.

These minerals are crucial in maintaining fluid balance in the body and proper muscular contraction. An imbalance of these minerals can lead to muscle cramping and fatigue or even stroke and coma on a severe level.

A balanced diet full of fresh fruit, vegetables and unprocessed foods can provide most of your mineral needs.

Here’s a list of some foods that you can include into your diet to ensure you’re optimizing your electrolytes!

If you’re training intensely outside and sweating heaps, you may need to supplement in order to replenish lost electrolytes. Some products I recommend are:

  • Nuun tablets
  • Ultima Replenisher
  • *Jessie do you want to plug Tailwind Nutrition here?
  • Or simply, adding lemon juice and high quality sea salt into your water bottle!

Carbs & Protein are your friends

Level up your training and recovery by adding in some carbs during and after your sessions. Carbohydrates help the body hold onto water, so you can stay hydrated throughout your workout. Many hydration formulas may already have added carbs in them, so look out for those; otherwise, you may want to look into adding in some carbs and protein with your electrolyte boosting beverage, especially if you’re doing high volume/high intensity training.

The amount will vary from person to person, but a general guideline is 30-50g of carbs in 500-600mls of water. Using a glucose-based carb like dextrin or dextrose instead of fruit juice or regular sugar will help promote glycogen replenishment in the muscles, rather than just in the liver.

Adding 15-20g of protein (from a protein powder) into that drink can also help to prevent muscle breakdown and boost the recovery process. We generally suggest a 2:1 ratio of carbs to protein, but you could go as high as 4:1 if your sessions are really intense. Again, everyone’s needs are different, so take the time to play around and see how you feel in and out of your workouts.

Make sure you’re always following up your training with a balanced meal of carbs, fat and protein to help optimize your recovery!

How to set up your hydration around your training

  1. 30 minutes prior to training, sip on half a litre of water (with electrolytes, if desired – especially it’s going to be a long session and you’re a ‘salty’ or heavy sweater).
    Chugging a ton of water just before your session is probably a bad idea for your stomach and it won’t be absorbed in time anyway.
  2. For low intensity or short workouts (under 60 mins), you’ll do just fine with plain water. Sip on 500-750ml during your session to satiety. If it’s hot out and you find yourself sweating a lot, you may want to add some electrolytes.
  3. For high intensity or long workouts over an hour, drink 500ml of water with added electrolytes per hour. Add 30-50g of carbs + 15-20g of protein for improved energy and recovery.
  4. Sip on another 500-750ml of water with your post-workout meal. If you were sweating buckets or your session was really long, you may want to top up with more electrolytes post-workout as well.

I’ll keep saying it, water intake and electrolyte needs are completely individual. You may need more or less depending on your training/competition conditions and your body’s ability to adapt. Try things out, see how you feel, and tweak your performance protocol to suit your individual needs. 


Dolan, Shaun H. “Electrolytes: Understanding Replacement Options.” ACE Fitness, www.acefitness.org/certifiednewsarticle/715/electrolytes-understanding-replacement-options.

El-Sharkawy, Ahmed M., et al. “Acute and Chronic Effects of Hydration Status on Health.” Nutrition Reviews, vol. 73, no. suppl 2, 2015, pp. 97–109., doi:10.1093/nutrit/nuv038.

Maclin, Alex. “Hydration for Performance: Hydration Strategies to Prevent Muscle Cramps, Perform Better & Recover Faster.” AlexMaclin.com, 26 May 2018, www.alexmaclin.com/blog/hydration-for-performance.

“MINERAL FUNCTIONS.” Nutritional Therapy Association.

Popkin, Barry M, et al. “Water, Hydration and Health.” Nutrition Reviews, vol. 68, no. 8, 1 Aug. 2010, pp. 439–458., doi:10.1111/j.1753­4887.2010.00304.x.

Riebl, Shaun K., and Brenda M. Davy. “The Hydration Equation.” ACSMʼs Health & Fitness Journal, vol. 17, no. 6, 2013, pp. 21–28., doi:10.1249/fit.0b013e3182a9570f.

Sawka, Michael N, et al. “Exercise and Fluid Replacement.” Medicine & Science in Sports & Exercise, vol. 39, no. 2, 2007, pp. 377–390., doi:10.1249/mss.0b013e31802ca597.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.