Guide for athletes on when to drink

Posted on February 19, 2019 by

Losing large amounts of fluid has a negative effect on training performance. Athletes can use this guide to assist in avoiding dehydration in training and competition.


Here’s what happens when you are dehydrated:


1. Your muscles fatigue and lose strength

2. Your heart has to work harder to pump blood to the body

3. Your mental focus and concentration decreases 

4. Your temperature control is impaired and generally leads to fatigue as the body slows down


Fluid requirements will vary between athletes even within each individual from day to day depending on the workload, sweat rate, environment and conditions that the individual training in.


Before Training

Two hours prior to training or the evening before, drink 10ml/kg of body weight. If it’s a long / hot / outdoor session, make this from a sports drink such as Powerade.

Directly before training, weigh yourself and remember that amount in kilograms.


What to  Drink? Conditions
Hot Cold
Duration  Short
(< 60 min)
Pre activity = Sports drink (such as Powerade)
During = Water
Pre activity = Water
During = Water
(> 60 min)
Pre activity = Prehydrate with sports drink and water prior to training to load fluid stores
During = Powerade + Water – alternate
Pre activity = Water + carb snack for energy
During = Sports drink (such as Powerade) to top up energy levels


During Training

Drink regularly throughout training where possible – up to 250ml every 15 – 30min.


After Training

Weigh yourself after training to monitor any changes in body weight. Body weight losses, beyond regular body weight, will equate to the amount of fluid lost, 1kg lost in body weight from regular body weight = 1L sweat/fluid loss. This should be replaced by 150%. eg = 1.2kg lost = 1.8L to consume following on top of regular intake. You won’t have to replace preloaded stores.

Water, sports drinks, electrolyte powders and low fat milk are the best choices for rehydration directly after activity when large sweat loss is experienced.

Rehydration can take time over a number of hours, it doesn’t have to be consumed all at once.


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Can you substitute Electrolite tables for Powerade, for eg. Rehyrdate tablets? If so, how important is it to follow the instruction for Rehydrate: 1 tablet to 250mls water?

    Hi Nicole, thanks for your question. Powerade has been made to a concentration to allow for the water and electrolytes to be rapidly absorbed. If you are using electrolyte tablets in water you should check to see that the company tells you that when he tablet dissolved in water the drink is isotonic to aid the absorption of both the water and electrolytes…

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