Run for the Journey

Run for the Journey

How to Stay Cool Running in the Heat

Realising that we were going to be doing a trail half marathon on the hottest day this year was a good prompt to think about how to stay cool running in the heat. 

Not everyone might be racing so we’ve also considered tips for staying cool when you’re just out training.

Hydrate, hydrate and hydrate

It’s important to hydrate frequently both before and during a run.   

Before the run

The general rule is to drink 500ml of fluid two hours before a run – water, a sports drink or diluted fruit juice – and another 150ml just before you set off.   The best way of knowing whether you’ve drunk enough water, is to check the colour of your urine (it should be a very pale yellow).

During the run/race

During the run or race you may need to drink a few sips of water every few minutes.  That’s why it’s better to carry your own water and not just rely on water stations.  The best way of carrying water with you is either by using a Camelbak or equivalent.  Or alternatively use a runners’ plastic bottle with a handle or an Iffley Road soft flask. We recommend filling these with water rather than energy drink but supplementing the water with gels every 45 minutes.

After the run/race

It’s equally important to continue drinking water once you get back from your run.  If you want to understand exactly how much water to drink once you’re back from your run, you need to weigh yourself both before and after running.  For more detail you should consult this excellent article Runners World Guide to Hydration for runners.

Running down a path in summer heat

Pour water over your head

It’s proven that pouring water over you is one of the most effective ways of cooling down.  Studies have shown that pouring a 250 ml cup of water over you will get rid of 607KJ of heat (45 calories) versus drinking 250 ml which gets rid of only 39KJ (9 calories).  For more details check out this article in Runners World.

Personally we recommend a mixture of drinking and pouring water over your head.

Look for the shadier path

If you’re not racing but simply doing a training run, it’s worth thinking about adjusting your route to remain in the shade for as much of the run as possible.  Some runners like the pattern of doing the same run every week, but even if you do there may be a path parallel to the one you’re on which is slightly shadier. 

You can take this to extremes as we did when training for an Ironman by repeating a short loop over and over to simulate a long training run – simply because it was much shadier than the normal long run.

Run earlier in the day

If you get the chance to run earlier in the day, do so.  The difference in temperature between running at 8am or Midday on a hot day can be significant.

Acclimatise to the heat

If you know in advance that it's going to be hot - for example you're planning to race abroad - it's well worth the effort acclimatising to the heat. Whilst preparing for his Kona Ironman Optima Racing Team Coach James Beckinsale acclimatised by spending up to 30 minutes in a sauna. If you do this, we recommend starting with a few minutes and only increasing time in the sauna very gradually.

 Dress for the heat

We recommend a cap, shades, vest and shorts in order to remain as cool as possible.  And remember to go for lighter colours as these reflect more of the sun’s heat.


It’s definitely worth investing in a decent pair of shades.  It’s worth looking at Sunwise or if you’re feeling more flush,  Oakley also does a good range.

Legionnaire’s cap

The most effective type of caps are legionnaires caps as they keep the sun off your neck and shoulders.  It’s challenging to find good ones which are light enough for running.  It’s worth checking out triathlon specialists where such caps are more often found.


A vest will keep you a lot cooler than a tee shirt in intense heat.  We recommend our Lancaster vest which is made from super-soft highly wicking drirelease pique.

Lancaster maple stripe running vest


We recommend our Pembroke, Hampton or Thompson shorts, which are made from a light Italian technical microfiber.

Pembroke running shorts


It’s even worth finding thin running socks as this can also make a difference.

It’s very unpleasant to be running when your feet feel too hot. Feetures do a good range of ultra-light ones.

Enjoy the warmer weather!

So with the hotter summer weather, we hope you have plenty of opportunities to try out our tips and still stay cool.

And, don’t forget your suncream!

We’d love to hear any of your suggestions about staying cool while running in the heat so please email us your tips at

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