High school sports teams start practices soon in what has been an extremely hot summer in much of the country. Now, before they hit the field, is the time for athletes to start slowly and safely building up strength and stamina.

Studies have found that the greatest risk of heat illness occurs in the first two weeks of team practices, while players’ bodies are still getting used to the physical exertion and the heat. Being physically ready to start increasingly intense team practices can help reduce the risk.

I am an athletic trainer who specializes in catastrophic injuries and heat illnesses. Here’s what everyone needs to know to help keep athletes safe in the heat.

Why should athletes restart workouts slowly?

One of the biggest risk factors for developing dangerous exertional heat illnesses is your physical fitness level. That’s because how fit you are affects your heart rate and breathing, and also your ability to regulate your body temperature.

If an athlete waits until the first day of practice to start exercising, their heart won’t be able to pump blood and oxygen through the body as effectively, and the body won’t be as adept at dissipating heat. As a person works out more, their body undergoes changes that improve their thermoregulation.

That’s why it’s important for athletes to gradually and safely ramp up their activity, ideally starting at least three weeks before team practices begin.

There is no hard and fast rule for how much activity is right for preparing – it varies by the person and the sport.

It’s important to remember not to push yourself too hard. Acclimatizing to working out in the heat takes time, so start slow and pay close attention to how your body responds.

How hot is too hot for working out outside?

Anything that is hotter than normal conditions can be risky, but it varies around the country. A hot day in Maine might be a cool day in Alabama.

If it’s significantly hotter outside than you’re used to, you’re more likely to get a heat illness.

To stay safe, avoid exercising outside in the hottest periods. Work out in the shade, or in the early mornings or evenings when the sun’s rays aren’t as hot. Wear loose clothing and light colors to dissipate and reflect as much heat as you can.

Hydration is also important, both drinking water and replenishing electrolytes lost through sweating. If your urine is light-colored, you are likely hydrated. Darker urine is a sign of dehydration.

What does acclimatization look like for teams?

Once team practices start, many states require heat acclimatization processes that gradually phase in activity, though their rules vary. Some states require 14 days of heat acclimatization. Some require six days or none. Some only require it for football.

Athletes who get a head start on acclimatization can help their bodies adapt faster and more efficiently to the heat. Regardless of what your state requires, all athletes participating in all sports should acclimatize carefully.

Heat acclimatization involves adding more strain during the workout every few days, but taking care not to add too much.

For example, instead of starting the first day of practice with full pads and full contact in football, players might start with just the helmets for the first few days.

Acclimatization is also about limits: Holding practice only once a day in the beginning and capping how many hours players practice each day can help avoid putting too much strain on their bodies too fast. Coaches and athletic trainers must also keep an eye on the wet bulb global temperature – the combination of heat, humidity, radiation and wind speed – to gauge the heat risk to players and know when to limit or cancel practice.

This isn’t just for football. Whether it’s soccer, track and field, softball or baseball, heat illnesses do not discriminate. A Georgia basketball player died after collapsing during an outdoor workout in 2019 – she was accustomed to practicing indoors, not in the heat.

What are warning signs an athlete is overheating?

If a player starts to slow down or gets lethargic, that may be a sign that they’re overheating. You might see evidence of central nervous system problems, such as confusion, irritability and being disoriented. You might see someone stumbling or trying to hold themselves up.

Most of the time, someone with exertional heatstroke will be sweating. They might have red skin and be sweating profusely. Sometimes a person with heat stress can lose consciousness, but most of the time they don’t.

What should you do if someone appears to have a heat illness?

If someone appears to be suffering from heat illness, cool them down as fast as possible. Find a tub you can put the person in with water and ice. Keep their head out of the water, but cool them as fast as possible.

Immersion in a cool tub is best. If you can’t find a tub, put them in a shower and put ice around them. Even a tarp can work – athletic trainers call it the taco method: Put the patient in the middle of the tarp, put some water in with ice, and hold up the sides to oscillate them slowly so you’re moving the water from side to side.

Every sports team should have access to a cooling vessel. About half the states require it. As that expands, these safety practices will likely trickle down to youth sports, too.

If a player appears to be suffering from heatstroke, cool them down and call 911. Having a comprehensive emergency action plan ensures that all personnel know how to respond.

What else can teams do to prepare?

Exertional heatstroke is a top cause of sports-related death across all levels of sports, but proper recognition and care can save lives.

Athletic trainers are vital for sports programs because they are specifically trained to recognize and manage patients suffering from exertional heatstroke and other injuries. As hot days become more common, I believe all sports programs, including high school sports programs, should have an athletic trainer on staff to keep players safe.

Samantha Scarneo-Miller, Assistance Professor of Athletic Training, West Virginia University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to This email address is being protected from spambots. You need JavaScript enabled to view it..

Is it possible that one day we could make Mars like Earth? – Tyla, age 16, Mississippi

When I was in middle school, my biology teacher showed our class the sci-fi movie “Star Trek III: The Search for Spock.”

The plot drew me in, with its depiction of the “Genesis Project” – a new technology that transformed a dead alien world into one brimming with life.

After watching the movie, my teacher asked us to write an essay about such technology. Was it realistic? Was it ethical? And to channel our inner Spock: Was it logical? This assignment had a huge impact on me.

Fast-forward to today, and I’m an engineer and professor developing technologies to extend the human presence beyond Earth.

For example: I’m working on advanced propulsion systems to take spacecraft beyond Earth’s orbit. I’m helping to develop lunar construction technologies to support NASA’s goal of long-term human presence on the Moon. And I’ve been on a team that showed how to 3D-print habitats on Mars.

To sustain people beyond Earth will take a lot of time, energy and imagination. But engineers and scientists have started to chip away at the many challenges.

A partial checklist: Food, water, shelter, air

After the Moon, the next logical place for humans to live beyond Earth is Mars.

But is it possible to terraform Mars – that is, transform it to resemble the Earth and support life? Or is that just the musings of science fiction?

To live on Mars, humans will need liquid water, food, shelter and an atmosphere with enough oxygen to breathe and thick enough to retain heat and protect against radiation from the Sun.

But the Martian atmosphere is almost all carbon dioxide, with virtually no oxygen. And it’s very thin – only about 1% as dense as the Earth’s.

The less dense an atmosphere, the less heat it can hold on to. Earth’s atmosphere is thick enough to retain enough heat to sustain life by what’s known as the greenhouse effect.

But on Mars, the atmosphere is so slight that the nighttime temperature drops routinely to 150 degrees below zero Fahrenheit (-101 degrees Celsius).

So what’s the best way to give Mars an atmosphere?

Although Mars has no active volcanoes now – at least as far as we know – scientists could trigger volcanic eruptions via nuclear explosions. The gases trapped deep in a volcano would be released and then drift into the atmosphere. But that scheme is a bit harebrained, because the explosions would also introduce deadly radioactive material into the air.

A better idea: Redirecting water-rich comets and asteroids to crash into Mars. That too would release gases from below the planet’s surface into the atmosphere while also releasing the water found in the comets. NASA has already demonstrated that it is possible to redirect asteroids – but relatively large ones, and lots of them, are needed to make a difference.

Making Mars cozy

There are numerous ways to heat up the planet. For instance, gigantic mirrors, built in space and placed in orbit around Mars, could reflect sunlight to the surface and warm it up.

One recent study proposed that Mars colonists could spread aerogel, an ultralight solid material, on the ground. The aerogel would act as insulation and trap heat. This could be done all over Mars, including the polar ice caps, where the aerogel could melt the existing ice to make liquid water.

To grow food, you need soil. On Earth, soil is composed of five ingredients: minerals, organic matter, living organisms, gases and water.

But Mars is covered in a blanket of loose, dustlike material called regolith. Think of it as Martian sand. The regolith contains few nutrients, not enough for healthy plant growth, and it hosts some nasty chemicals called perchlorates, used on Earth in fireworks and explosives.

Cleaning up the regolith and turning it into something viable wouldn’t be easy. What the alien soil needs is some Martian fertilizer, maybe made by adding extremophiles to it – hardy microbes imported from Earth that can survive even the harshest conditions. Genetically engineered organisms are also a possibility.

Through photosynthesis, these organisms would begin converting carbon dioxide to oxygen. Eventually, as Mars became more life-friendly to Earthlike organisms, colonists could introduce more complex plants and even animals.

Providing oxygen, water and food in the right proportions is extraordinarily complex. On Earth, scientists have tried to simulate this in Biosphere 2, a closed-off ecosystem featuring ocean, tropical and desert habitats. Although all of Biosphere 2’s environments are controlled, even there scientists struggle to get the balance right. Mother Nature really knows what she is doing.

A house on Mars

Buildings could be 3D-printed; initially, they would need to be pressurized and protected until Mars acquired Earthlike temperatures and air. NASA’s Moon-to-Mars Planetary Autonomous Construction Technologies program is researching how to do exactly this.

There are many more challenges. For example, unlike Earth, Mars has no magnetosphere, which protects a planet from solar wind and cosmic radiation. Without a magnetic field, too much radiation gets through for living things to stay healthy. There are ways to create a magnetic field, but so far the science is highly speculative.

In fact, all of the technologies I’ve described are far beyond current capabilities at the scale needed to terraform Mars. Developing them would take enormous amounts of research and money, probably much more than possible in the near term. Although the Genesis device from “Star Trek III” could terraform a planet in a matter of minutes, terraforming Mars would take centuries or even millennia.

And there are a lot of ethical questions to resolve before people get started on turning Mars into another Earth. Is it right to make such drastic permanent changes to another planet?

If this all leaves you disappointed, don’t be. As scientists create innovations to terraform Mars, we’ll also use them to make life better on Earth. Remember the technology we’re developing to print 3D habitats on Mars? Right now, I’m part of a group of scientists and engineers employing that very same technology to print homes here on Earth – which will help address the world’s housing shortage.

Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to This email address is being protected from spambots. You need JavaScript enabled to view it.. Please tell us your name, age and the city where you live.

And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.

Sven Bilén, Professor of Engineering Design, Electrical Engineering and Aerospace Engineering, Penn State

This article is republished from The Conversation under a Creative Commons license. Read the original article.