大熱天穿什么衣服最涼快？答案不是一件大白T那么簡單。衣服的顏色、面料、松緊都會影響你的體感。

As the world continues to grapple with extreme heatwaves, which are becoming ever more regular thanks to climate change, the clothing we wear is a vital component in how we stay cool. Researchers have found that by wearing appropriate clothes, it is possible to turn the air-conditioning up by 2C (3.6F) – which over the long term would save considerable energy, both saving money and cutting greenhouse gas emissions.

全球還在繼續(xù)與極端熱浪作斗爭，而且受氣候變化影響這種極端天氣越來越頻繁，而我們所穿的衣服對于保持涼爽十分關(guān)鍵。研究人員發(fā)現(xiàn)，如果穿對衣服，空調(diào)可以調(diào)高2度，長期來看可以節(jié)省不少電，既能省錢，還能減少溫室氣體排放。

So what should you wear to stay cool?

那么穿什么衣服才會涼快呢？

Colour and design

顏色和設(shè)計(jì)

When it comes to colour, most people wear white in the summer – because white reflects the sun's rays, rather than absorbing the light like black does.

說到衣服顏色，大多數(shù)人在夏天穿白色衣服，因?yàn)榘咨芊瓷涮柟饩€，而不像黑色會吸收光線。

However, heat doesn't just come from the sun – it comes from our bodies too. When that heat from our bodies hits the white clothing, it is reflected back at us.

然而，不僅太陽會釋放熱量，我們的身體也會散發(fā)熱量。來自身體的熱量遇到白色衣服，就會反射回身體。

In 1980, a study of why Bedouins – an indigenous, semi-nomadic people who inhabit desert regions in the Arabian peninsula, Middle East and North Africa – wear black robes in the desert, found that heat exposure was the same whether tribal members wore black or white robes.

1980年，一項(xiàng)研究想知道在阿拉伯半島、中東和北非的沙漠地區(qū)活動的半游牧原住民貝都因人為什么在沙漠中穿黑色長袍，結(jié)果發(fā)現(xiàn)，這些部落成員無論穿白色還是黑色長袍接觸到的熱量都一樣多。

How is that possible?

這怎么可能呢？

Black coloured fabrics absorb heat emanating from the body – so this can also play a role in cooling your body down. The Bedouin's secret is wearing loose-fitting black clothing, especially if it's windy. The loose black clothes heat up the space between the fabric and the skin, promoting an upward air current – like a chimney – and providing cooling relief.

黑色面料吸收了身體散發(fā)的熱量，因此黑色衣服有助于給身體降溫。貝都因人的秘訣在于他們穿寬松的黑色衣服，尤其在有風(fēng)的日子里。寬松的黑色衣服讓面料和皮膚之間的空間升溫，從而形成了向上的氣流，就像煙囪一樣，從而讓身體涼爽下來。

So the fit of the clothing is actually more important than the colour. However, if you are going to be wearing tight-fitting clothing, then stick with white. Fabrics with texture – such as seersucker or pique, a fabric often used in sports polo shirts – also help to lift clothing off your skin.

所以衣服的松緊其實(shí)比顏色更重要。不過，如果你要穿緊身衣服，那就穿白色的。有紋理的面料，比如泡泡紗或翻領(lǐng)運(yùn)動衫常用的珠地網(wǎng)眼面料，也有助于讓衣服和皮膚不緊貼在一起。

Material matters

面料很重要

"In terms of clothes, it's better to have a material that allows water vapour to pass through so that it doesn't block the sweat evaporation." says Rhett Allain, associate professor of physics at Southeastern Louisiana University. "Some of the newer sports-based materials do this. Cotton does not do so great with this."

東南路易斯安那大學(xué)的物理學(xué)副教授瑞特·阿蘭說：“衣服要涼快，最好是采用能讓水蒸氣通過的面料，這樣才不會阻止汗液蒸發(fā)。有些新型運(yùn)動面料能做到這點(diǎn)。棉布的透濕性則要差一些。”

Uncoated cotton, linen, nylon and polyester are all classed as breathable fabrics to some degree – meaning they allow sweat and heat to escape through the material.

沒有涂層的棉布、亞麻、尼龍和滌綸都有一定的透氣性，這意味著汗液和熱氣都能通過這些面料。

Cotton absorbs moisture but it doesn't dry quickly, so if you're sweating a lot your clothes will stay wet, making them less comfortable. Linen is widely worn as it has excellent breathability due to its large fibres, but like cotton it is slow to dry. Merino wool has been a popular choice for outdoor enthusiasts as it's breathable and wicks moisture without retaining odour.

棉布吸濕卻不能速干，所以如果你流很多汗，衣服就會濕濕的不舒服。很多人愛穿亞麻衣服，因?yàn)閬喡榈拇掷w維賦予其極佳的透氣性，但是和棉一樣，亞麻干得慢。美利奴羊毛既透氣又吸濕排汗而且不會留下汗臭味，因此受到戶外運(yùn)動愛好者的歡迎。

Nylon and polyester are used in most activewear as they wick moisture and dry quickly – but they retain odour. Research has also shown that nylon has a higher moisture absorption and better wicking capabilities than polyester, but is slower to dry. Synthetic fibres like nylon and polyester can feel uncomfortable when they get wet though, and one study suggested wearing clothing made of bamboo, which is a low conductor of heat, and doesn't compromise on comfort.

尼龍和滌綸吸濕排汗又速干，因此被應(yīng)用在多數(shù)運(yùn)動裝中，但是這兩種面料不防臭。研究表明，尼龍的吸濕排汗能力比滌綸更強(qiáng)，但是比滌綸干得慢。不過，尼龍和滌綸這樣的化纖面料濕掉后會讓穿著者感到不舒服。一項(xiàng)研究指出，穿竹子制成的衣服導(dǎo)熱性低，而且舒適度高。

So it turns out that picking an outfit to stay cool is a little more complex than simply throwing on a white T-shirt. But the right fabric and appropriate fit when possible should help you keep your temperature down when the mercury heats up – and save on air-conditioning too.

可見，穿什么衣服才能涼快是個(gè)有點(diǎn)復(fù)雜的問題，不是一件大白T就能解決的。但是合適的面料和剪裁在大熱天能幫你降溫，也能節(jié)省空調(diào)電費(fèi)。

英文來源：BBC

翻譯&編輯：丹妮