For some people, summer is the time to head indoors to exercise. But others welcome the heat as a way to sweat more and get a better workout.

　　对一些人来说，夏天是出门锻炼的好时候。但另一些人则认为夏天的高温能够使他们出更多的汗，因此也能得到更好的锻炼。

　　Indeed, I’ve long regarded the sweatiness of my exercise sessions as a sign of how hard I was pushing myself. But it turns out I’ve been wrong: How much you sweat doesn’t necessarily correlate with how intense your workout is or how many calories you burn.

　　事实上，我一直认为在锻炼过程中出汗是代表我努力运动的标志。但事实证明我错了：你出汗的程度不一定与你锻炼的强度和燃烧多少卡路里有关。

　　When your body temperature rises, your eccrine glands secrete sweat, and the evaporation of moisture from your skin helps you cool off. Of course, sweating can occur for other reasons, such as stress or fear.

　　当你的体温上升时，你的分泌腺就会分泌出汗液，然后在你皮肤表面蒸发帮你降温。当然，出汗也可能是其他原因，比如压力或恐惧。

　　That type of sweat comes from the apocrine glands, which are located mainly in the underarm and groin.

　　汗液来自于腋下和腹股沟处的顶泌汗腺。

　　How much we sweat during exercise is due to a number of factors, including gender (men tend to sweat more than women) and age (younger people sweat more than older people) as well as genetics, temperature and humidity.

　　我们在锻炼中流汗多少取决于一些因素，这些因素包括性别(男性比女性更容易出汗)和年龄(年轻人比老年人出汗更多)以及基因、温度和湿度。

　　Weight plays a role as well. Larger people tend to sweat more, because their bodies generate more heat.

　　体重也起着一定的作用。更胖的人更容易出汗，因为他们的身体会产生更多的热量。

　　Another contributor is fitness level. Surprisingly, fit people tend to sweat sooner during exercise and more copiously than those who are less fit.

　　而另一个因素就是健康水平。令人惊讶的是，与那些不太健康的人相比，健康的人在运动中更容易出汗。

　　Research suggests that as your fitness level improves, your body’s heat-regulating system becomes more efficient, cooling you down faster and allowing you to work harder.

　　研究表明，随着你健康水平的提高，你身体的热量调节系统会变得更有效率，让你更快地降温，进而使你能够更努力地工作。

　　Don’t be misled by the loss of a few pounds after a high-sweat workout. This is simply water weight that you gain back when you rehydrate and doesn’t necessarily mean you’ve burned lots of calories.

　　在大量排汗运动过后，不要被体重的减少所误导。因为此时你体重减轻的重量只是你体内流失的水的重量，当你补充水分后就又会恢复，这并不意味着你燃烧了大量的卡路里。

　　On the flip side, don’t assume that a low-sweat workout means you aren’t working hard enough or burning enough calories. It could be that your sweat evaporates quickly because you’re exercising in air-conditioning, near a fan or outdoors on a windy day. Or, unlike me, you simply may not sweat much.

　　另一方面，不要认为低汗锻炼就意味着你没有努力锻炼或燃烧足够的卡路里。可能是因为你在空调房里锻炼，在风扇或风天的户外运动，你的汗水很快就会蒸发。或者，你们跟我不一样，你们出的汗比较少。

　　Whatever the case, wearing clothing made of synthetic fabrics such as polyester or Lycra can help you feel less sweaty. These pull (or wick) sweat from your skin to outer layers of the clothes, where the moisture evaporates.

　　无论如何，穿合成纤维的衣服，比如涤纶或莱卡，可以让你感觉不那么出汗。那些从你皮肤产生的汗水会马上渗入到外层的衣服上然后从那里蒸发。

　　Cotton, on the other hand, absorbs moisture but doesn’t promote evaporation. As a result, your shirt or other clothing can feel soaked and heavy after a workout.

　　另一方面，棉花吸收水分，但不促进蒸发。因此，你的衬衫或其他衣服在你锻炼后会有湿透并有沉重感。

　　A drawback of polyester is that it tends to stink more than cotton after exercise. In one study, researchers collected the sweaty shirts of 26 subjects after an hour of intensive spinning. The next day, trained sniffers determined that the polyester shirts smelled worse than the cotton ones.

　　涤纶材质衣服的一个缺点是它在运动后比棉花更容易发臭。在一项研究中，研究人员在经过一个小时的大强度训练后收集了26个受试者的汗湿衬衫。第二天，受训过的嗅探员发现涤纶衬衫的气味比棉质衬衫更难闻。

　　Micrococci, a type of bacteria that break down sweat and cause unpleasant odor, were found to grow only on the polyester garments. That’s important because sweat itself is generally odor-free; it’s the combination of sweat and certain bacteria that literally raises a stink.

　　微球菌是一种能分解汗液并引起难闻气味的细菌，它们只生长在聚酯服装上。这一点很重要，因为汗水本身通常是无异味的，只有汗水和某些细菌结合后才会引起臭味。

　　You can find "odor-resistant" synthetic fabrics, which are treated with various antibacterial compounds. Among the most common is silver, typically applied in tiny amounts known as nanoparticles.

　　你可以找到由各种抗菌化合物处理后“耐异味”的合成纤维。其中最常见的是微小的银纳米颗粒。

　　But some research suggests that silver-treated clothing may not work as well as promised to reduce bacteria and odor. What’s more, a significant amount of the silver may come out in the wash, reducing the effectiveness of the garments and potentially harming the environment.

　　但一些研究表明，采用银处理的衣服可能不像厂家承诺的那样能够减少细菌和气味。而更重要的是，大量的银可能会在清洗过程中散失，从而降低衣服的功效，并可能对环境造成污染。

　　There are also concerns that exposing our skin to silver nanoparticles may pose a health risk, though there’s no direct evidence for this.

　　还有人担心，皮肤与纳米银颗粒直接接触也可能会造成健康风险，尽管目前没有直接证据。