[Printable Version of This Page]

Sweat Is Valuable

Sweat—it fades the armpits in your favorite clothes. It stinks up your sneakers. It makes your skin unpleasantly damp and itchy.

It saves your life.

It might even save a robot’s life.

Sweat helps regulate your body temperature. When you get too hot on the surface, you’re in danger of heating up inside as well. And that’s not good. Because, while your skin can tolerate a wide range of temperatures, your brain, hormone systems, and core organs cannot. So when your temperature rises, your pores open. You sweat. Sweat evaporates, and you cool down a bit. Your body temp stays in the safe zone.

Sweat might also help us develop robots, including prosthetics, that could work efficiently in a wider range of temperatures.

A team at Cornell University has developed a soft robot hand that cools off with machine sweat. The hand has pores that are normally closed. But if the temperature rises above 86°F (30°C), the pores open and water sweats out.

This machine sweat would allow artificial hands or other robots to continue working in environments where fans and air conditioning are not available to keep them cool and running. 

Unfortunately for the robots, they can’t just quaff a bottle of Gatorade and replenish their fluids. That’s the next problem for developers to solve.

Meanwhile, you don’t have that challenge. But you might have a failure to act, nonetheless. As we age, our ability to notice thirst (dehydration) weakens.  This effect is so common that 75% of Americans have some level of chronic dehydration.

So, first rule: If you are thirsty, you are dehydrated.

Staying hydrated has multiple benefits. It may boost your metabolism. It reduces the risk of kidney stones. It can improve your memory and mood. And it can boost your energy.

Then there’s “glow.” As Southern Belles insist, they aren’t subject to sweat. They just glow. That’s actually true in a way. Sweating brings blood to the surface to increase warm coloration and nourish the skin.

How much is enough water or other fluids per day is open to question. The standard advice to drink 8 glasses would not be enough if you are in a very hot environment or exercising intensely. Less than that might be OK for some people.

At the other extreme, the National Academy of Sciences, Engineer, and Medicine has studied the issue and recommends 11.5 glasses of fluid per day for women and 15.5 for men.

Hardly any of us get that much.  The best advice is probably to get 8 glasses or more and watch yourself. If you feel thirst, raise your intake. If your urine is dark yellow, raise your intake.  And always replenish after exercise.

Health Library Archives