How to Hydrate During Training and Racing

How do you know if you are hydrating properly in training and racing? Ruth Martin reveals the essential tips to ensure you hydrate correctly for performance and health

Pic credit: Photo by Martin Sanchez on Unsplash

What effect does dehydration have on performance?

Our bodies are made up of 60% water, which we use to control our body temperature, brain function and join lubrication in every day life. Imagine the pressure that training and racing adds to that.

Dehydration occurs when you lose too much fluid through sweating and don’t replace it. It can result in a lack of energy, brain fog and muscle cramps. Just two percent of bodyweight loss due to dehydration lead to a drop of six percent in running performance.

This means your heart has to work harder to pump blood around the body as the blood becomes thicker, fatigue sets in and you will slow down.

Less common but just as, if not more serious, is Hyponatremia. This happens when you take on too much fluid, diluting the sodium levels in the blood.

The result is nausea, vomiting, disorientation and sometimes even death. . A study in 2019 found that 14% of runners on the start line of the 153 mile Spartathlon race were mildly over-hydrated (hyponatremic). This over-drinking is likely due to pre-race nerves, and a worry that you haven’t drunk enough.

So how do you know how much you should drink?

Getting the Hydration Balance Right

Keep an eye on the colour of your urine and how often you go to the loo. If you are only going 2-3 times a day and your pee is dark, ‘Dry Spell’ on the Pantone Highland Spring scale, you are very likely dehydrated. On the flip side, if you visit the loo more than 8 times a day and your pee is very clear, you could be drinking too much.

Women should drink 2.2 litres (about 9 cups) of fluid per day from drinks, and yes, a daily cup of coffee can be included in this count. The caveat is to remember that absolutely everyone is different and your ‘normal’ may well be different to that of your training partners.

Listen and tune in to what your body is telling you; if you feel thirsty, this is usually a sure sign that it would be a good idea to take on some fluid.

‘Keeping hydrated before a long run, bike ride or endurance event is important for your performance and overall health,’ explains GRTW founder, and run and tri coach, Rachael Woolston. ‘Water – hydration is literally the oil for our brains, body and joints.’

When should you drink in training and racing

The relationship between dehydration and performance is very individual, dependent on weight, how hard or intense your train and race, where you are in your menstrual cycle and even lifestage (check out our Peri and Menopause Performance on-demand programme). Drink as and when you need and consider the following three factors to guide you:

  • How hot is it?
  • How long will I be out training or racing?
  • Am I a heavy sweater?

Practise, Practice, Practice

The best thing to do, is to practise, just as you do race pace, fuelling and kit. Ensuring you try out how to hydrate optimally in training, will help support a better experience on race day.

Plan out your hydration strategy for races including how you are going to be able to access your fluids, be it bottles on the bike, carrying water in a running pack or utilising aid stations for top ups. Remember to consider your rehydration strategy for after your training session or race too. Drink little and often post event, guided by your thirst.

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