🥵 How Much Is Heat Slowing Me Down? Use This Running Pace Calculator to Find Out
Running in the summer can feel like running through soup.
You’re putting in the work…
...but your watch says otherwise. 😑
So if you’re wondering, “How much is heat slowing me down?”
This post (and a free heat calculator) has your answer.
Why Your Running Pace Drops in Hot Weather
Now that the sun’s cranked up, I’ve noticed something…
🔥 My pace is tanking.
And it’s not just a little slower—it’s noticeably off.
But here’s the kicker...
It feels like I’m running strong.
Then I check my GPS pace?
Boom. Reality check.
Is It Just Me? (Spoiler: It’s Not)
Let’s clear this up:
👉 As the temperature goes up, your pace goes down.
👉 But your effort level? It stays the same (or even increases).
That’s the tricky part.
What feels like your usual pace on a 15°C day can feel like a death march at 30°C.
Hot Weather Running Feels Harder for a Reason
Here’s why this matters:
When it’s hot, your body is working overtime to stay cool.
More blood goes to the skin to regulate temperature...
...which means less oxygen for your working muscles.
Translation?
🏃 You’re running at the same effort…
🕒 But your pace takes a hit.
That’s why I always say:
Run for time, not distance—especially in the summer.
My Breaking Point (And Lightbulb Moment)
Last summer, I was running in 30°C heat here in Waterloo.
Felt like I was crushing it.
Sweat pouring. Legs moving. Feeling Good.
Then I looked at my watch.
😬 Waaay off my usual pace.
At first, I was frustrated.
But then I remembered something that flipped the script.
This Running Heat Calculator Changed Everything
A while back, I came across a free running pace calculator from Runners Connect.
It adjusts your pace based on the temperature.
(Yes, it does the math for you.)
I plugged in my numbers and…
BOOM 💥
Turns out, my “slow” pace was actually on par with my usual.
Meet the Experts Behind This Heat Adjustment Calculator
This tool wasn’t just thrown together.
It was developed by:
- 🧠 Jeff Gaudette (Founder of Runners Connect)
- 🏃♂️ Jack Daniels (Yes, that Jack Daniels—legendary running coach)
Together, they built one of the most accurate pace calculators out there.
And the best part?
It doesn’t just explain why you’re slower in the heat…
👉 It tells you exactly how much to adjust your expectations.
Don’t Let the Heat Psych You Out
So, if you’ve been asking yourself…
“Is the heat really slowing me down?”
“Why does my pace feel off even though I’m pushing hard?”
“How do I adjust my running pace in summer?”
Now you’ve got your answer. ✅
- Yes, heat affects your pace.
- No, you're not getting slower.
- And yes, this pace / heat calculator can help you train smarter.
So bookmark it. Use it. Trust it.
And most importantly?
Keep running.
Use the temperature calculator before a run to adjust your pace
It's even better to use it before you go out for the run to adjust your pace.
From Runners Connect:
Use this calculator on your workout days to adjust your goal pace according to the weather outlook. All the temperatures are for the “feels like” temperature, which takes into account both heat and humidity. For example, if you have a 10k tempo run scheduled, simply calculate how long it will take you to finish the entire run (i.e., if you’re running 6 minute pace, your total time would be a 36 minute 10k). Plug in your time and see how much you should adjust your pace for the given temperatures.
Try it, it will make your training more enjoyable this summer by managing your expectations of what you consider to be a good run.
