To our U.S.-based readers, we hope you kept your cool and made it safely through summer’s first proper heatwave. Although temps have dropped about 30 degrees outside our Boston HQ, we probably haven’t seen the last of sweat-soaked training sessions. To help prepare, we’re turning to this new piece from our training partner Greg McMillan: “A Complete Runner’s Guide to Running and Racing in the Heat.” Greg notes that while running in the morning in some locations can be cooler, it may be more humid, forcing a “pick your poison” choice against hotter, less humid afternoons. He advises that regardless of when you run, you should be leery of your usual pace and heart rate guidelines, as they become unreliable in the heat. Greg suggests paying extra attention to your breathing and the “Talk Test” as a more accurate gauge of your effort. Luckily, your body does get better at handling these conditions after about 10-14 days. Your system learns to sweat earlier and increase plasma volume. For more on that, you can check out: “Heat Training Like a Pro is Hell. Here’s What I Learned,” Outside’s Alex Hutchinson tested a protocol with the goal of gaining heat benefits without disrupting training. The bedrock of the program is a 30-minute run in 100°F heat, followed by a 104°F hot tub soak to extend thermal stress without trashing the legs. One key discovery was the author’s personal blind spot: even as his core temperature climbed above 100°F, he rated his perceived warmth as 3 out of 10 for quite a while. A crucial part of heat training is learning to recalibrate your internal thermostat to accurately judge how hot you truly are, because your body might be cooking long before you feel it. (See: frog & pot.)

#HeatCheckYourself