THE opportunity for me to go for a run in a sweltering “heat chamber” with an ultra-marathon legend is a bit like a pub league footballer being offered the chance to train with Real Madrid.
And with the nickname of Sweaty Dave – given to me after nearly flooding the office while struggling through a pathetically-mild curry – and the chance to find out just how much I really do perspire, I knew this was a chance I should not waste.
What better way to find out how sweaty I am than by running in a 39C heat chamber with an ultra-marathon expert?[/caption]
Pierre, in pink, in Precision Fuel and Hydration’s heat chamber (I’m sweating in the blue behind him)[/caption]
The Marathon des Sables is considered the hardest foot race in the world… and Pierre loves it[/caption]
I enjoy 5km park runs (best time 22m) and am training for a half-marathon across the South Downs in May (hoping to finish under two hours and avoid serious injury/embarrassment).
So running for around 40 minutes in a small room where temperatures come close to the hottest day EVER in the UK was always going to be a challenge, for me at least.
Not so much for my co-runner Pierre Meslet, a veteran of two Marathon des Sables (MDS) – the seven-day, 160mile run across the Sahara Desert in 50C which is widely acknowledged as the hardest foot race in the world.
And while I was slightly concerned about collapsing through dehydration or drowning in a pool of sweat, London-based Frenchman Pierre, 40, could not wait to get going in the 39C man-sized microwave.
Which is little surprise for someone who doesn’t consider the MDS – which has tragically claimed three lives in its 39-year history – a challenge, but simply an “adventure”.
His tales of completing six marathons in seven days through deep sand and relentless Moroccan heat – and winning the team event in 2023 – while carrying all your own supplies and sleeping in a tiny tent packed with other stinky runners, made me suspect we were cut from different cloth.
Learning that he also managed to complete a similar event through the rainforests of Costa Rica despite breaking his ankle on only the second day confirmed this.
I had actually felt almost calm as I approached the facility at the New Forest HQ of Precision Fuel and Hydration, a pioneering company which has helped tens of thousands of elite athletes around the world by showing them how and what they sweat.
But I knew the renowned ponies and idyllic-sun dappled woods that lined the roads on the way there were just a brief reprieve from what lay ahead.
On arrival I was given an at-rest sweat test to find out not how much I sweat, but what I sweat.
A small device triggered the sweat glands in my arm, while another contraption collected my sweat.
Analysts then revealed how much sodium I lose in my sweat (around 635mg/litre, which apparently makes me a “low salty sweater”).
These tests are a key part of PFH’s work as it means they can provide athletes with a highly-specific hydration plan, in terms of electrolyte content and volume, so they perform at their best.
(In a nutshell, people who are very salty sweaters will need to take more sodium supplements to maintain the correct balance and avoid peeing treacle or sweating out all the water they drink)
They have 50 centres in over 20 countries around the world and have helped people from all sorts of sports – including rugby and, to my slight shock, golf – since they started in 2011.
It took ages for me to provide a sufficient sample. Was this a sign that my Sweaty Dave nickname of the past 15 years was actually undeserved?
I was about to find out.
Much to my pleasant surprise, when I did finally step inside the heat chamber I was actually just rather warm and cosy, rather than terrified.
My living room was not even hot, and I was losing up to 2.4ltrs of sweat in one hour
Pierre Meslet
So instead of worrying about the heat, my anxiety now switched to running on a treadmill – something I’d only done once before.
My fears were well-placed as soon after easing into my 40-minute run I somehow tripped myself up and nearly collapsed on to the running belt.
Once I’d assured Lindsey, the senior sports scientist who was closely monitoring me, that I wasn’t dying, just completely ashamed, I continued my pursuit of perspiration.
All the while I could hear the relentless whirr of Pierre’s treadmill and his thundering footsteps as he approached a pace of close to 13km/hr – almost double what I was doing.
Play it cool, I told myself though, and after ten minutes I felt pretty good.
I was actually enjoying the pace and relishing all the gains my increasingly-moist body was making.
With Pierre having my sweat test, which threw up a few surprises[/caption]
My results revealed that I’m a ‘low salty sweater’[/caption]
Heat chambers offer many benefits, including lowering your core body temperature and improving the ability to sweat more (the secret’s in the levels of plasma in the blood).
This reduces the risk of overheating when exercising and allows elite athletes to push themselves harder.
They can also provide competitors with a psychological reassurance that they can handle the heat when preparing for events in hot climates.
These massive improvements don’t take long to kick in either, with Pierre needing just ten one-hour sessions in the fortnight before the MDS to acclimatise his body.
A range of other top sportspeople have headed to the PFH lab too, including Tour de France stage winners Jan Bakelants and Victor Campernaerts and South African Ironman icon James Cunama.
Motor-racing driver-turned-TV star Billy Monger completed nine heat sessions in the lead up to his Ironman World Championship challenge for Comic Relief, before becoming the prestigious Kona event’s fastest ever double amputee.
If you can’t get to Precision’s New Forest HQ, or don’t want to splash roughly £1,000 on ten heat chamber sessions, there are other ways to achieve a similar effect.
Pierre, who spent three days camping in the Dubai desert in preparation for one event, has tried one alternative.
He explained: “I’ve got a treadmill at home and a sauna suit – which is basically a long sleeve plastic T-shirt and some plastic trousers which you get on Amazon for around £40.
“For the first three or four days I wore just that, with shorts underneath. You’re already sweating quite a bit, then by day five you increase a layer under that, then the layer becomes a long-sleeve layer. Then you add a sweatshirt on top of that.
“By the end of it, two days before the event, I was wearing four layers plus the sauna suit.
“My living room was about 21C, which is not even hot, and I was losing up to 2.4ltrs of sweat in one hour.”
To be fair they do warn you before you get in the chamber[/caption]
It was thirsty work as the run went on[/caption]
By the end of it I was dripping, gasping… and relieved to get out of there[/caption]
“Luckily” for me, I was able to save on my heating bill and use Precision’s chamber instead. And as I approached 20 mins of my session I was becoming less comfortable… and more moist.
Then after half an hour, with sweat pouring and my heart-rate at around 160bpm, Lyndsey decided it was time to dial down to walking pace.
No doubt PFH’s insurance company would have approved.
That’s when I really noticed the impact of the heat. As I stepped off the treadmill, rather than the usual sensation of cooling down, I felt no such comfort.
Instead, I actually felt quite desperate to get out of there and feel some fresh air on my face.
Thankfully I was ushered outside, where I could take on some much needed water (with extra sodium) and watch in amazement as Pierre continued to crash out a few more miles.
The dad-of-two – who somehow juggles his ultra-marathon feats with his job as a physio and osteopath – even had a smile on his face as he did it, which I found bizarre.
As I slowly dried out, the big question was: How much did I sweat and am I really that sweaty?
Another trip to the scales, having weighed myself before my run, and a few calculations based on how much I’d drunk in the chamber revealed I was sweating at 1.33 litres per hour.
So was this a lot?
Not replacing fluids adequately can be the difference between peeing red and being in contention at the front of a race
Smashing the myth, and creating the need for a new nickname, Lindsey explained: “Although you didn’t lose a huge amount of sweat, we would consider that below average in terms of sweat loss in these conditions.
“There’s not exactly an average sweat rate for the average person doing the average type of exercise as things vary so much between individuals but also your sweat rate changes dramatically depending on what you are doing.
“The average for our non-pros in the lab might be something like 1.6 ltr/hr, so it’s still quite high and unsustainable.
“Doing an outdoor easy run in 10C people might range from 0.25ltr/hr to 1 ltr/hr depending on their running speed, running economy, acclimation status, clothing, body shape and size.
“The ranges we’ve seen in the heat of the lab are 3.21 ltr/hr (max) and 0.84 ltr/hr (min).
“Both yourself and Pierre (1.8ltrs/hr) still lost more fluid per hour than it’s generally feasible to replace during prolonged exercise.
“As Pierre explained from his experience on the MDS, not adequately replacing those losses can be the difference between being peeing an uncomfortable hue of red during MDS or in contention at the front of the race.”
So with this new-found understanding of my sweatiness, would I be willing to take Pierre up on his offer of joining him on the MDS next year?
Are killer blisters, blinding sun, wearing the same clothes for seven days and carrying everything I need to survive on my back while gasping through the burning desert “adventures” I think I could cope with?
Probably not.
But with PFH’s personalised hydration plan to guide me I certainly felt better prepared to take on my half-marathon in seven weeks’ time.
Or avoid serious embarrassment, at least.
If you want to check out the heat chambers, would like a personalised hydration plan or more info on any of the above head to Precision Fuel and Hydration’s website here or find them on Instagram here
Pierre using some treasured fluid to treat his battered feet[/caption]
Pierre carries everything he needs for the event, including food, on his back, although there are water stations to rehydrate[/caption]
Billy Monger is one of many top sport stars to use the labs at Precision Fuel and Hydration[/caption]
Victor Campernaert gears up for a session inside Precision’s heat chamber[/caption]
