Every endurance runner knows that hydration is important in training and for racing but often we are unsure of why and how to get it right.

So in this post we are going to look at Optimal Hydration for Runners. We’ll recap on why optimal hydration for runners is important. We’ll have a look at what can happen if we misjudge our hydration requirements? Finally we’ll review some tips on what you may consider to your hydration is optimal.
Why is Optimal Hydration for Runners Important?
Did you know that hydration is a performance limiting factor in exercise over 90 minutes, so an an endurance runner you can understand why hydration is key.
If you are in a situation where you are >2% dehydrated this may result in the following physical/psychological symptoms:

• Decreased heat dissipation
• Increased core temperature
• Increased rate of muscle glycogen use
• Poor Concentration
• Changes to Short-term memory

NOTE: Over-hydration could cause gastric upset, hyponatraemia (which is a condition of low sodium in your blood) this may happen in prolonged sweating combined with excessive fluid/water consumption. Symptoms include dizziness, muscle cramping, confusion, and bloating. Severe cases can lead to seizure, coma, and even death.

ACSM Position Stand:
Because there is considerable variability in sweating rates and sweat electrolyte content between individuals, customized fluid replacement programs are recommended
Sawka, M. N., Burke, L. M., Eichner, E. R., Maughan, R. J., Montain, S. J., & Stachenfeld, N. S. (2007). American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc, 39(2), 377-390.

For performance and personal health and safety optimal hydration is paramount

Good Practices  

• Ensure adequate hydration pre exercise
• Drink to thirst
• Increase intake in heat
• Electrolyte drinks during prolonged exercise and under hot conditions
• Ensure reasonable access to fluids during training
• Assess Your Hydration status
• Environment – note the weather, consider the distance, timings, access to drinks

Listen to your body and tune into the environment – assess individual needs rather than ‘one size fits all’

What to Drink:
Drinking plain water (filtered or tap) is readily available and in our view the best way to be hydrated. There are a few ways you can enhance your water either for taste or to help manage your hydration, energy and electrolyte status. If you like your water flavoured then consider infusing with slices of lemon, lime, orange or berries or slivers of cucumber. You may wish to add a tiny amount of honey or some electrolyte drops (our favourite is Elite Drops).
Try our recipe for a homemade energy drink (great for drinking at home or even filling your water bottle for your training runs).

Everyday Hydration is Foundational – if you’re hydrated before starting a training run or a race you’ll have a great foundation to maintain an optimal hydration status so ideally:

• Drink 2L of water per day ( 6-8 large glasses)
• Form a habit
• Try hot water and lemon/mint/ginger
• Drink herbal teas
• Flavour your filtered water – chilled – ice – flavour lemon/lime slices, berries, cucumber
• Have a bottle with you at all times – sip throughout the day
• Have some water before leaving the house
• Have a glass of water by your bed

Hints and Tips to Stay Hydrated when you are running, start by drinking some water before you start your run and plan to carry a water bottle for all runs over 1 hour long. It’s a good idea to know where you can top up with water e.g. if it’s a long training run is there anywhere you can top up your water bottle or if it’s a race are you aware of where the water stations are on the route. Remember to add some electrolyte tablets or drops to your water bottle (practice doing this on non race days too so your body adapts and gets used to this). If you don’t like carrying a water bottle consider a camelbak water carrier.

What about Sports Drinks as an alternative or addition to water?

They are designed to provide added glucose to make fluid easier to absorb and are a carbohydrate energy source (500ml tends to provide 20-30g glucose). Some brands include electrolytes to replace those lost in sweat. Sometimes the sweet taste reduces the perception of effort during an endurance run.

The pitfalls of sports drinks

Often they have a high sugar content, they may contain artificial sweeteners e.g.  sucralose, aspartame, acesulfame potassium (acesulfame K) and flavourings. Artificial sweeteners are a particular concern as some are thought to be carcinogenic, have neurological/behavioural consequences from chronic use, and may lead to headaches and migraines.

Are artificial sweeteners good for weight loss?

There is a theory that consumption of artificial sweeteners may lead to weight gain – thought to be due to sweeteners not being able to breach Blood Brain Barrier therefore brain does not acknowledge satiation i.e. you’re driven to eat/drink more sugar. NOTE: research on humans is limited, hence the lack of conclusive evidence on long-term effects in humans.
So the message is if you wish to use a sports drink consider using it strategically to enhance energy alongside your hydration plan.

Choosing natural alternatives

• Drink water (this is may be all you need…it will depend on your training schedule)
• Choose an energy/sports drink free from artificial sweeteners
• Choose an energy/sports drink containing natural fruit flavours
• Introduce coconut water (a good source of the electrolyte potassium)
• Ultimately…..Make your own energy drink (see electrolyte recipe in this post)