It doesn’t matter how fit you are – running in hot weather is hard. Still, there are ways you can prepare for the heat in order to get the most out of your runs and recover a little faster.
Why is running in the heat so hard?
When you run in the heat, your body temperature goes up. As a result, blood is pushed to the skin in order to facilitate sweating. The problem is, that blood would normally be used to push oxygen around to your muscles – so running starts to feel a lot harder.
If you train with a heart-rate monitor then you may notice that towards the end of runs in the heat that your heart rate goes up even if you aren’t pushing any harder. This is known as cardiac drift: as you get dehydrated, your blood gets more viscous (a bit thicker), so your heart has to work at a higher rate to pump it around.
Dry heat versus humidity
Everyone has an opinion as to what kind of heat is ‘harder’, but the truth is that they’re both hard for different reasons.
Perspiration is how we cool ourselves down, but anyone who has tried to run in areas of high-humidity will notice that they don’t ever seem to be able too. That’s because sweating only works to cool you down when it is able to evaporate, which it can’t do when there is too much water in the air due to humidity.
On the other hand, if you’re in a dry climate in the middle of summer, then the low humidity causes sweat to evaporate at a rate almost as fast as you can generate it. The result is dehydration kicking in a lot faster than in high-humidity climates, which is only made harder by the altitude – but that is a topic for a different time.
How to feel better in the heat
Going into a run in the heat not properly hydrated is a recipe for disaster, as all the detrimental effects of dehydration will kick-in a lot sooner. However, pre-hydrating with water and electrolytes will push back the onset of dehydration during your run. This is particularly important if you run in the mornings, as most of us will lose up to around 500mL/16oz of water overnight from respiration.
2. Leave some bottles out
If you’re driving to where you start your run, try and drop a few bottles off along the way or the night before. For those who do loops as part of their run, have a bottle or two waiting for a regular pit-stop. Load them with ice or keep them in the freezer overnight so they’re still cool when you get to them. A solution of SOS will increase your water absorption and will replace what you lose when you sweat, so you’ll feel better during the run and recover a lot faster than if you only use water.
3. Forget about pace
Sometimes in the heat you need to throw your pace out the window. The increase in body-temperature is also going to coincide with an increase in perceived exertion, so don’t get too attached to your splits, just get the effort in.