Running in the Heat: Adjusting Your Pace & Expectations
On Tuesday, I did my first workout this year in what I consider to be hot conditions. 88 degrees (Fahrenheit). After enjoying cool temperatures in the 40s and low 50s this spring, running in the heat sort of feels like propelling myself into a brick wall. As I rounded the track for my first warm-up lap, I was trying to figure out why my legs felt like lead and my lungs were already fighting me.

Growing up in Florida and now living in Atlanta, I’m used to experiencing heat and humidity for a large portion of the year. But that first workout when the season changes is always a doozie. Confession: I’m a wimp when it comes to running in the heat.
When the weather changes, our expectations and our actions must also change. We have to remember, understand and accept that our bodies react differently to heat. As the temperatures rise, so do our heart rates and perceived effort. We simply can’t expect to continue to run the same paces we were running consistently during the winter and early spring, nor should we from a health and safety standpoint.
So what can we expect? One of my running coaches always provided me this guidance: For every degree over 65 degrees Fahrenheit, plan to slow your pace by 2 seconds per mile. So if my average pace is 8:15, when the weather is 88 degrees, I should expect to run about 46 seconds slower – around a 9-minute mile (88 degrees – 65 degrees = 23; 23 x 2 seconds = 46 seconds; 8:15 + 0:46 = 9:01).
Here’s what the experts at Running Times suggest:
“For every 10-degree increase in air temperature above 55 degrees, there’s a 1.5 percent to 3 percent increase in average finishing time for a marathon … this slow-down occurs because heat impacts runners at a physiological level through various means, including dehydration, increased heart rate and reduced blood flow (and subsequently oxygen) to the muscles used for running.”
It gets in my head. Shakes my confidence. Going from my best running to feeling much less than my best. It takes time to adjust to the looming summer temps. But we need to remember that it’s not only ok, but advised, to adjust our paces and evolve our goals until the fall rescues us again.
In a recent article in Competitor Magazine, editor Mario Fraioli shared why this is so important:
“If your average heartrate on a typical tempo run performed under near-ideal conditions is in the range of 165 to 170 beats per minute, on a hot, humid day, trying to maintain that type of effort will yield a number in the neighborhood of 190. While you do everything in your power to stay ‘on pace,’ you’ll also be working dangerously close to your max heartrate and exerting yourself at an effort level that’s much greater than it should be for that given workout – or is even safe, for that matter. The best thing to do in this sort of situation is to aim for your normal heart-rate numbers (or, if you don’t wear a heart-rate monitor, the same effort level) keeping in mind that, in the end, your average pace will be a few ticks per mile slower than usual. For example, if the pace of your tempo runs is typically 7:00 per mile, under oppressive conditions the same sort of heart-rate (or effort) might turn out to be 7:15 per mile. This is OK! Your body doesn’t know the difference between a 7:00 mile and a 7:15 mile, but physiologically, you’re still getting the same benefit. The same principle applies to interval workouts — slow down, but keep the effort level the same.”
I wish my normal pace under hot, opressive conditions was 7:15 *wink.* I’m working on it.
Here was my workout from Tuesday. Three words: Hurt. So. Good.
10 rounds of 4 exercises with descending reps, with either a 400-meter run or 120 jump ropes between each round:
- 400-meter run
- 10 burpees, 10 push-ups (on toes), 10 kettle bell thrusters lifting 40 pounds (squat while thrusting 2 20-pound kettle bells overhead with a shoulder press), and 10 slam balls with a 15-pound medicine ball (holding a medicine ball over your head, slam it to the ground as you come to a squat and repeat).
- 120 jump ropes
- 9 burpees, 9 push-ups, 9 kettle bell thrusters and 9 slam balls
- 400-meter run
- 8 burpees, 8 push-ups, 8 kettle bell thrusters and 8 slam balls
- 120 jump ropes
- 7 burpees, 7 push-ups, 7 kettle bell thrusters and 7 slam balls
- 400-meter run
- 6 burpees, 6 push-ups, 6 kettle bell thrusters and 6 slam balls
- 120 jump ropes
- 5 burpees, 5 push-ups, 5 kettle bell thrusters and 5 slam balls
- 400-meter run
- 4 burpees, 4 push-ups, 4 kettle bell thrusters and 4 slam balls
- 120 jump ropes
- 3 burpees, 3 push-ups, 3 kettle bell thrusters and 3 slam balls
- 400-meter run
- 2 burpees, 2 push-ups, 2 kettle bell thrusters and 2 slam balls
- 120 jump ropes
- 1 burpee, 1 push up, 1 kettle bell thruster and 1 slam ball
It took me just more than 35 minutes to complete. I’m hot and tired just remembering it. But what doesn’t kill you makes you stronger, right? Right.
Hydrate, hydrate, hydrate. And be patient.
Does slowing down in the heat shake your confidence or do you embrace the adjustment? What other tips do you have for working out or running in the heat?