Heat Training: Why does heat slow your pace?
Why Running Feels Harder in the Heat
If you’ve ever wondered why your pace drops on hot days, you’re not imagining it, heat really does make running tougher. Here’s what’s happening inside your body:
Higher heart rate & effort: Warm weather raises your heart rate, so the same pace feels harder.
Cooling takes priority: Your body works harder to keep itself cool, pulling resources away from performance.
Blood flow shifts: More blood is sent to the skin to release heat, leaving less for your working muscles.
Sweat loss adds up: Sweating leads to fluid and electrolyte loss, increasing your risk of dehydration.
Brain protection mode: To prevent overheating, your brain sends signals to slow down.
Faster fatigue: As your core temperature climbs, muscles tire more quickly.
Bottom line: Slowing down in hot weather isn’t weakness, it’s your body’s way of protecting you and making sure you can keep training safely.
The Benefits of Heat Adaptation
While the heat makes running feel harder, training in it can actually make you stronger. With consistent exposure, your body gradually adapts; a process called heat acclimation.
Here’s how it helps:
You begin sweating earlier and more efficiently, improving cooling.
Blood plasma volume increases, which enhances circulation.
Your body becomes better at directing blood where it’s needed most.
The same effort starts to feel easier, even at higher temperatures.
Once the weather cools, these adaptations can give you a performance boost.
Of course, heat adaptation should be approached gradually. Listen to your body, give yourself time, and prioritize safety, especially in extreme heat.
Smart Summer Running Tips
Running safely in the heat comes down to preparation and adjustments:
Time it right: Run in the early morning or evening to avoid peak heat.
Hydrate smart: Drink water before, during, and after your run.
Dress light: Wear breathable, moisture-wicking clothing with UPF protection.
Protect skin & eyes: Sunscreen, hats/visors, and sunglasses are essential.
Stay cool: Freeze water bottles overnight so they melt slowly on your run.
Recover well: Keep electrolyte popsicles in the freezer for a refreshing recovery boost.
Replace electrolytes: Carry it if you’re a heavy sweater.
Being a summer runner isn’t just about toughness—it’s about being responsible, protecting your body, and adjusting to the conditions so you can train consistently.
Final Word
Running in the heat is challenging, but it’s also an opportunity. By respecting your body’s limits and adapting smartly, you not only stay safe but also build resilience that will pay off in the cooler months.
