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Mission Workshop 37.5 PNG Jersey review

8 Jan 2019

Nice-looking jersey, but hard to test all that's claimed is real

Cyclist Rating: 
• Nice design • Nice fit • Central pocket big enough
• Not lived up to the claims • Expensive

One thing is for sure: 37.5 (a sports brand based in Boulder, Colorado, USA) would win for best 2018 marketing campaign if I were the referee. Why? Well, if you’re bold enough to launch a cycling kit with the tagline 'Stop losing. Start Doping' – and then use a picture with a syringe to illustrate the campaign – you have balls. And people will stop and read what you want to say. At least I did.

37.5 claims that its technology 'helps keep your body at the ideal core temperature of 37.5° Celsius and helps keep the microclimate next to your skin at the ideal relative humidity of 37.5%.'

Meaning that 'when you’re hot, patented active particles embedded in the material remove sweat in the vapour stage before liquid sweat forms, cooling you down.'

At the other end of the spectrum, 'when you’re cold, those same active particles trap your energy to help warm you up.' And this also answers the question of why it uses the numbers 37.5 as the name of the brand.

How does it work?

How it's done is a whole different story. 37.5 explains that its cycling kit (the jersey and bib shorts’ name is PNG) is made with volcanic sand, which contains the active particles that remove the sweat in the vapour stage and trap energy when it’s cold.

37.5 didn’t answer the question 'what kind of particles are these, from a scientific point of view', but responded through a spokesperson, saying: 'This sand comes from one particular volcano in the world, the location of which we consider a trade secret.

'Volcanic sands differ wildly. We needed an active particle that was extremely porous, adsorbed and desorbed moisture and absorbed infrared (IR) light in the spectrum that the human body emits it.

'The particle absorbs human IR light and then if moisture is present, meaning you’re hot, it uses that energy to evaporate the moisture. If no moisture is present it holds onto that energy as warmth.'

In other words, the material used by 37.5 – because of these active particles – is able not only to adsorb and desorb moisture, but also to trap the IR light emitted by the body.

I had to research this because I really had no clue and yes, if you didn’t know, your body actually emits IR light. The same IR light that your body emits is supposed to activate the particles in the material and make them adsorb and desorb moisture when you’re sweating, or – alternatively – trap the IR light when it’s cold and keep you warm.

But that’s not all: 37.5 also claims that the material can extend an athlete’s performance by 10 minutes, or 26%.

The science behind it

The technology was developed by Dr. Gregory Hagguist, a Phd in photo-physical chemistry. In 1992, Hagguist travelled to the volcanic sand baths of Mount Aso, Japan.

He first thought he would be able to stand the heat only for a few minutes, but once buried in the sand he found out it was actually pretty comfortable.

That is when he wondered if the comfort he experienced came from the balance between heat gain and heat loss. The volcanic sand he was buried under made the sweat vapour from his skin evaporate so fast that he was continually cooled. And that was the inspiration behind the material he later developed with 37.5.

A study of the University of Colorado Boulder [“Beneficial effects of cooling during constant power non-steady state cycling” published on the Journal of Sports Medicine] compared the 37.5 material to standard cycling kit and to an ice jacket circulating water at 4°C.

The researchers tested 14 elite athletes while pedalling at their lactate threshold for 60 minutes. The test was performed for three weeks and every athlete performed the test once a week.

If they couldn’t hold their lactate threshold, the test was stopped, and their body temperatures were monitored by a wireless pill and rectal thermometer (along with more ‘regular’ scales like weight and sweat loss, blood composition change, CO2 exhale and O2 inhale tests performed during and after the tests).

The result? The average stop time for the testers wearing the 37.5 technology was 49 minutes, versus 39 minutes for those wearing the standard jersey and 52 for those wearing the cooling jacket.

Within the pro peloton, the team Katusha-Alpecin has adopted the technology for its kit.

Find out more about the Mission Workshop 37.5 PNG jersy here:

Our test

I tested two sizes of this jersey. The medium size was a bit too large and had too much space around my shoulders, so I went down to a small.

The small was probably a bit too tight, but if you’re looking at aerodynamics a tight fit is the way to go. The design of the 37.5 cycling kit is really nice and looks great, with minimal graphics but good attention to detail (like the extra pocket for the phone in the back and a small hole for sunglasses in the front).

During one of the last long rides I had during the autumn, I found the central pocket of the jersey useful and of a good size, but the lateral ones are a bit too small if you want to store any large layers, and were quite hard to get to (a bit too high).

Maybe because the small size was really tight or because with this material you don’t need any extra layers?

To be honest, my overall sense of the promised body regulation was far beyond my abilities. On an outdoor ride, the jersey felt exactly the same as a classic one. If ride slow you get cold, if you ride hard you warm up.

But that is why I also wanted to give it a go indoors, so I tested it a few times on the turbo, both with and without a fan. On the first test with in a time trial position, I was initially impressed because I felt the sweat only dripping from my head and not around other parts of my body, like my chest.

But as soon as I started to cycle upright (with and without the fan, on two different occasions) the moisture dripped straight onto my belly and by the end I looked like I'd just done a HIIT class.

In reality I was only 30 minutes into my turbo session, and well below my lactate threshold (240 watts versus 290). The same result happened with both sizes of jersey.

So, despite the 'fair doping' marketing campaign, a scientific backbone, university research, a pro team using the kit and a great look and overall fit, unfortunately this jersey didn’t quite deliver what it claimed during my review period.

It’s still a nice jersey, but particularly with a £150 price tag, I was hoping it would live up to expectations.


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