Have you ever been running in the heat, feeling strong, and then suddenly, something feels off?
Maybe your legs start to feel heavy, your breath gets shorter, and before you know it, you feel dizzy—like you might collapse.
That’s heatstroke creeping in.
Let me tell you about a time when I found out just how serious heatstroke can be. It happened during the Solo Sorocarta Half Marathon in 2023. At first, everything was going great.
I was running a solid pace, and I was on track to run my first sub-1:30 half marathon. But as I hit around the 12th or 13th kilometer, I felt something strange.
My legs felt like they were made of concrete, and my breathing became labored. It wasn’t long before I started swaying on the road, feeling dizzy, and my vision got blurry.
I knew something was wrong, but I kept going.
That’s when I lost my balance and fell. Thankfully, a group of runners stopped to help me, and I was rushed to the hospital in an ambulance. I woke up in a clinic with no memory of what happened, feeling scared and confused.
It was one of the scariest moments of my life, and it taught me a crucial lesson: never ignore the signs of overheating.
Running in the heat is a challenge, but when you don’t listen to your body, it can quickly turn dangerous.
In this article, I’m going to share with you how to recognize heatstroke early, prevent it, and know what to do if it happens.
What is Heatstroke?
Heatstroke happens when your body gets too hot and can’t cool down quickly enough.
When you run, your body heats up from the effort.
To cool off, your body sweats and sends more blood to the skin. But when it’s extremely hot, and the air is humid, this process doesn’t work as well.
If you push too hard, your body can overheat, and your internal temperature can rise to dangerous levels—over 104°F (40°C). That’s when heatstroke kicks in.
And believe me, I’ve learned this the hard way. When the temperature is high and the humidity is through the roof, your body struggles to cool itself off, and things can get ugly fast.
Humidity makes it worse because sweat doesn’t evaporate as quickly.
It’s like running inside an oven with no air circulation. That’s why understanding how your body reacts in these conditions and taking steps to stay cool is crucial.
Dehydration and Overexertion
When it comes to preventing heatstroke, hydration is just one piece of the puzzle.
You could be drinking water constantly, but if you’re pushing yourself too hard in extreme heat without factoring in pacing and humidity, you’re still putting yourself at risk.
From my own experience, I’ve realized that while staying hydrated is essential, it’s equally important to adjust your effort level.
On particularly hot and humid days, your body’s ability to cool itself becomes less efficient.
This is when you need to take a step back and listen to your body. If you’re feeling drained, slow down and give yourself time to recover. Dehydration is the enemy.
The key is to match your hydration with your effort. Overexerting yourself without respecting the conditions can lead you straight into heat exhaustion or worse.
The Dangers of Heatstroke
You might think heatstroke is just about feeling hot or tired, but it’s much more than that.
If you push your body too hard and don’t cool down in time, heatstroke can cause serious damage.
Here’s what happens when heatstroke takes over:
- Organ failure: Your internal organs, like your kidneys and liver, can get damaged from overheating. If you keep going without cooling down, you risk your organs shutting down.
- Brain problems: Heatstroke can mess with your brain. You might feel confused, dizzy, or even pass out. In extreme cases, it can cause seizures or brain damage.
- Muscle breakdown: The intense heat can break down muscle tissue, releasing toxins into your blood. This can overload your kidneys and cause serious problems.
- Heart problems: Heat puts a lot of strain on your heart. You might experience a rapid heartbeat or, even worse, arrhythmia (an irregular heartbeat), which can be life-threatening.
- Long-term effects: Even after you recover from heatstroke, you might feel mentally and physically drained for days. Your body can be left in a weakened state for weeks or longer.
After my own heat exhaustion incident, I felt mentally and physically drained for days. That’s how powerful heatstroke can be—it doesn’t just affect your run, but it can linger and mess with your body even after the race is over.
Recognizing the Early Signs of Heatstroke
Heatstroke doesn’t just hit you suddenly.
There are warning signs that you can catch early.
If you recognize them, you can take action before things get worse. Here’s what to watch out for:
- Increased body temperature: Your skin will feel hot to the touch, and you may start to feel unusually warm.
- Breathing trouble: You might notice that it’s harder to breathe or your breathing becomes shallow and rapid.
- Dizziness and fatigue: You’ll start to feel drained, like you don’t have the energy to continue, and your head might feel light. If you’re feeling dizzy, that’s a sign you should slow down immediately.
- Red, flushed skin: When your body overheats, your face may become flushed, and your skin might look red or pale.
- Nausea: If you start to feel nauseous or sick to your stomach, that’s a major red flag that your body is struggling to cool down.
- Excessive sweating: While sweating is your body’s cooling mechanism, when it’s hot and humid, your sweat might not evaporate as it should, leaving you drenched.
The key is to listen to your body. The moment you feel any of these signs, stop running, get to a cooler place, and hydrate.
Temperature and Humidity
We all know how important the temperature is when you’re running, but have you ever thought about how humidity plays a role?
When the air’s saturated with moisture, your sweat doesn’t evaporate as quickly, making it harder for your body to cool down. It’s like running inside an oven with no ventilation.
In tropical climates like Bali, I’ve had to adjust my training because even when the temperature seems manageable, the humidity can make the heat feel unbearable.
The hotter the air, the harder your body works to regulate its core temperature.
Add humidity into the mix, and that job gets even harder.
That’s why it’s not just about how hot it is outside—it’s about how much moisture is in the air and how much your body can handle before it starts to overheat. Always be mindful of both when deciding whether or not it’s safe to run.
How to Prevent Heatstroke During Your Runs
Now that we understand what heatstroke is and how to spot the early signs, let’s talk about how to prevent it.
It’s all about smart planning, knowing your limits, and listening to your body.
Know your limits
Before heading out for a run in hot conditions, check the weather. If it’s over 32°C (90°F) or the humidity is really high, think twice. I’ve learned to recognize that even though I love running, some days the heat isn’t worth the risk. I make the call whether to run in the heat or skip it for safety.
Hydrate, hydrate, hydrate
Hydration is key in the heat. Start drinking water as soon as you wake up, and keep sipping throughout the day. During your run, carry water or electrolyte drinks with you. Hydrate regularly, even before you feel thirsty.
Adjust your run time
Run during cooler parts of the day—early morning or late evening.
In Bali, where the heat is intense, I’ve learned to avoid midday runs. The sun is hottest then, and your body can’t handle it. If you must run during the day, choose a route with plenty of shade or take breaks in shaded spots.
Pace yourself
Don’t worry about speed. On hot days, slow down, especially if it’s really humid. During heat training, I lower my expectations and listen to my body. On particularly hot days, I shorten the distance or switch to a slower pace.
Wear the right clothes
Wear lightweight, moisture-wicking clothing to allow your body to breathe. Avoid cotton—it’s a heat trap. I also wear light-colored clothes because they reflect the sun’s rays instead of absorbing them. A hat is also essential to keep your face cool, and sunglasses protect your eyes from the harsh sun.
Use cooling techniques
If it’s really hot, consider wearing a cooling towel or vest. These items help lower your body temperature and keep you feeling fresh. I personally love soaking my bandana in cold water before a run—it’s a simple trick but makes a big difference.
It’s More Than Just Water
When it comes to hydration during hot runs, water alone just won’t cut it—especially on longer runs. Yes, you need to stay hydrated, but you also need to replenish the electrolytes lost through sweat.
The importance of balancing water with electrolytes can’t be overstated. That’s why I always carry sports drinks or electrolyte supplements during longer runs.
These drinks help replenish essential minerals like sodium, potassium, and magnesium, which are crucial for muscle function and preventing cramps.
What to Do When Heatstroke Strikes
Alright, let’s talk about what happens if things go south during your run and heatstroke actually starts to take over.
Recognizing the situation early can save you (or someone else) from serious harm. It’s crucial to stay calm and act quickly.
Stop Running and Get to Shade
As soon as you feel the signs of heatstroke kicking in—whether it’s dizziness, confusion, or your body overheating—stop running immediately. Don’t push through. I can’t stress this enough: listen to your body. Find a shaded area, preferably with cool air, to help lower your body temperature.
Lie Down and Elevate Your Legs
Once you’re in the shade, lie down and raise your legs slightly. This helps improve blood circulation to your core and brain, which can help cool your body down. I’ve found this really helps when I start to feel faint—it gives my body a chance to reset and recover.
Hydrate Slowly
When you start feeling overwhelmed by the heat, don’t just chug water. You need to sip water slowly to rehydrate without overwhelming your system. Sports drinks are also a great choice because they replace the electrolytes you lose through sweating.
Cool Down Your Body
Now it’s time to cool off. If you have access to ice packs, place them on your neck, armpits, and groin area. These spots cool the body quickly. If you don’t have ice packs, wet towels or even a cold bath can work wonders.
Call for Help
If your symptoms are not improving after 10-15 minutes, or if you’re feeling faint or confused, seek medical attention immediately.
Heatstroke can escalate fast, and the sooner you get help, the better your chances of recovery.
Conclusion
There’s no shame in slowing down and taking a break when the conditions aren’t ideal.
By following these strategies and making smart choices, you can keep yourself safe from heatstroke and still enjoy the freedom and excitement of running in the summer.
Respect the heat, and it will respect you back.
Main takeaways:
- Hydrate properly before, during, and after your runs.
- Adjust your pace in hot conditions and listen to your body.
- Find shade and cool down when you start feeling the heat.
- Plan your runs for cooler times of day.