Temperatures routinely reach above 30 degrees under those scarlet silk-lined tunics and bearskins that Her Majesty’s Queens Guards wear while guarding places such as Buckingham Palace.
But on and off the battlefield, how do they keep cool I hear you ask?
Well, it is all down to discipline and doing the right thing during hot weather.
As Britain's temperatures soar during the latest heatwave, with a new record high set in Northern Ireland at 31.2C which could even be broken on Thursday, some tips on how to stay cooler might be welcome.
Queens Guards can spend anywhere between one to four hours in direct sunlight during the hot summer days standing guard at the royal palaces and it is a surprise that more of them do not faint while on parade.
The main reason is due to good HYDRATION. H20. OGIN. COLD WET. WATER … whatever you call it, make sure you drink plenty.
You should aim to drink at least eight glasses of water per day - but you will likely need much more, especially before, during and after Physical Training (PT).
When it comes to hydration, guardsmen prepare well in advance, by drinking plenty of water the day before any big parades - it is no good drinking water five minutes before you head out the door, it will be too late.
A good indicator to check that you are sufficiently hydrated, is to check the colour of your pee.
If your pee is dark in colour, this is a good sign that you may be dehydrated. You should aim to pee clear at least once a day.
Slap on your issued (free) sun cream while you can - you’ll miss that stuff once you’ve left the military (sun cream is ridiculously expensive on civvy street).
If you are in the field or on operations, don’t worry, whack on some camouflage cream - as it also protects the skin from the sun’s harmful UV rays.
Before any major parade, soldiers are encouraged to “salt load” - adding a little extra salt to your meals can increase plasma volumes in the blood, keeping you hydrated for longer.
Wear a hat. A jungle hat, a baseball cap, any hat. Just try to keep the sun off your face and back of the neck.
Loosen the cuffs on shirts and jackets if you have to wear them, this will increase cool air circulating around clothing.
Get out your bungees and tent pegs. Stay under cover if possible, even if it is only cover with a poncho.
Maybe ask your Quarter Master Sergeant for a few fans … good luck with that one though.
If not, open up some windows and doors to increase air flow in the block ... no fire doors though, no one wants an AGAI.
Not to be a bore. But it is a good idea to reduce your alcohol intake - as this can drastically impair your body’s ability to regulate its core temperature.
Lastly, my favourite way to cool down in the heat is to take a cold shower throughout the day when ever I get the chance.
Julian Perreira served with the Grenadier Guards for more than 14 years and spent many years on operations around the world.
From the jungles of Brunei, to the deserts in Afghanistan and the forecourt of Buckingham palace.
This is how he kept cool.
* This is an edited version of an article first published in 2020.