Tag Archives: Evaporative Cooling

Does a Base Layer Really Work in Tropical Weather?

Hot Weather Banner

Illustration courtesy of someecards.com

The Minister of Science, Technology and Innovation issued a media statement on 8th January 2016, in which he said that peninsular Malaysia will have hot and dry weather throughout the first quarter of the year.  A strong El Nino phenomenon is to blame.  We may see a rise in temperature of between 0.5 degrees Celsius and 2.0 degrees Celsius compared to the norm for this time of the year.

So far the recorded high temperatures in Kuala Lumpur support this.

Weather forecast KL

Data courtesy of http://www.weather.com

Hooray!  It is going to be hotter than normal for the next few months.

Staying cool in Malaysia’s humid tropical heat has been an ongoing challenge for me.  In previous posts I have chronicled the various things I have tried to stay cool while out on my bike.

The latest tool in my bag of tricks is a base layer.  The opinions on the efficacy of wearing a base layer in hot weather are mixed, to say the least.  Some riders think it is crazy to wear an additional layer under a jersey out in the heat.  Others swear by the ability of a good base layer to make a hot weather ride more comfortable.

I was persuaded by articles such as this one, titled “Why Wear A Base Layer In The Heat?“, which appeared in Cycling Tips.

I have worn a sleeveless base layer under a jersey on long rides for a few months now.

Audax BRM 200 Malaysia 2016 JM Air Kelapa Marco

Photograph courtesy of Marco

In the absence of riding with a rectal thermometer to provide quantitative data, I can’t tell you how many degrees cooler my core temperature has been with a base layer on.  Plus there are too many other variables to consider – ambient air temperature, level of exertion, hydration etc.

However I can report that in my case, a base layer does what it claims to, which is help keep me cool in hot weather.  My base layers  are much more breathable than my jerseys, which helps with evaporative cooling.  The same process that makes my arms feel cooler when I wet my arm screens.

I also feel more comfortable riding with a base layer on.  It wicks moisture away from my body, so I don’t have a soaked jersey clinging to me.

I can unzip my jersey and not have rivulets of sweat dripping down my torso.  For a heavy perspirer like me, this is a big plus.  It is also easier on the eye for my riding companions as I sit with an open jersey at rest stops.

An advantage of a base layer that most riders agree on is that the extra layer between jersey and skin provides some protection against road rash in the event of a fall.  I hope not to test that claim!

It is forecast to be at least 33° C / 91°F this Sunday, during the Pulau Indah 180.  My base layer says “Bring it on!”

Beat the Heat