Stay racing fit during the scorch of summer...

We asked Tony Cavanagh, Clinical Director at EMATS (regular medical providers at Nice Work events) about the dangers of running in super hot weather and what measures runners can take to avoid dehydration and the less commonly known hyponatremia, often caused by drinking too much water.

As the summer heat intensifies, runners face a unique challenge of staying hydrated while avoiding the risks of both dehydration and hyponatremia (low sodium). 

While dehydration occurs when the body loses more fluid than it takes in, hyponatremia results from excessive water intake that dilutes the body's sodium levels.
To strike a balance, it's crucial for runners to adopt smart hydration strategies when running in the heat. 

In this blog post, we will explore tips and techniques that can help runners maintain optimal hydration levels without compromising their sodium balance.

1. Understand your sweat rate:
Every runner's sweat rate is different, and understanding your body's response to heat and exercise is key to developing an effective hydration plan.
To determine your sweat rate, weigh yourself before and after a run, noting the amount of fluid consumed during the exercise. This helps estimate how much fluid you need to replenish during your runs to prevent dehydration.


2. Start hydrating before your run:
Preparation is key. Begin hydrating well before your run by consuming water or electrolyte drinks at least an hour in advance. This allows your body to absorb and distribute fluids, priming your system for the exertion to come. Aim for 470-590 ml (16-20 ounces) of fluid in the hour leading up to your run.

3. Incorporate electrolytes:
During prolonged exercise or in hot conditions, the body loses not only fluids but also essential electrolytes like sodium, potassium, and magnesium. To replenish these electrolytes, consider incorporating sports drinks or electrolyte tablets during your runs. These drinks or tablets can help maintain a balance between fluid intake and sodium levels, reducing the risk of hyponatremia. 

4. Hydrate regularly during runs:
When running in the heat, it's essential to drink fluids at regular intervals to avoid dehydration. Aim for approximately 120-240 ml (4-8 ounces) of fluid every 15-20 minutes, depending on your sweat rate and exercise intensity. Sip gradually, rather than gulping down large volumes, to optimise absorption and minimise the risk of stomach discomfort.

5. Monitor your urine colour:
One way to gauge your hydration status is by monitoring your urine colour. Clear or pale-yellow urine generally indicates adequate hydration, while darker urine suggests dehydration. Use this as a general guide to assess whether you need to increase your fluid intake.

6. Adjust your hydration plan based on duration and intensity:
The duration and intensity of your runs will impact your fluid requirements. For shorter runs or lower-intensity workouts, plain water may suffice. However, for longer runs (over an hour) or more intense workouts, electrolyte drinks are recommended to replenish lost sodium and other essential minerals.

7. Listen to your body:
Remember to listen to your body's signals during your runs. If you feel excessively thirsty or experience muscle cramps, it may indicate the need for more fluids or electrolytes. Don't ignore these signs, as they can be early indicators of dehydration or sodium imbalances. Swollen hands, nausea, vomiting, confusion, and restlessness are also common symptoms of hyponatraemia. 

8. Medical care:
It is important to understand your body and the need for medical intervention should it be required. During planned running events, the onsite medical team will be available to assist you in cases of emergency. However, following the tips outlined above, hopefully we won't need to intervene!  

Hydration is a vital aspect of any runner's routine, especially when facing the challenges of running in the heat. By understanding your body's needs, incorporating electrolytes, and adjusting your hydration plan accordingly, you can strike the right balance between avoiding dehydration and preventing hyponatremia. Remember everybody is different, so you may need more or less water/ electrolytes than your running team or partner. Prioritise smart hydration strategies, stay tuned to your body's signals, and enjoy your runs while keeping hydrated and healthy throughout the summer months.

Race safe, race happy!

We would like to thank our friends at EMATS for contributing this blog our website.