Does your heat training match your event?

You’ve entered a hot-weather event. Now you’re looking at the forecast, wondering whether the heat you can train in at home will prepare you for the heat waiting at the start line.

The temperature is only part of that question. A dry afternoon and a sticky morning can ask different things of your cooling system.

An October study compared eight days of dry and humid heat acclimation in trained male cyclists. The crossover study reported 10 riders in the dry condition and 12 in the humid condition. Riders completed 30-minute time trials before and after, in both climates: 42°C at 25% humidity and 33°C at 80% humidity, matched for a heat-stress index.

In the dry time trial, power improved by 14 watts after dry preparation, versus 6 watts after humid preparation. The estimated advantage was 8 watts, with a 90% credible interval of 2–15 watts.

In humid conditions, either approach helped similarly: 12 watts after dry preparation and 9 watts after humid preparation.

That suggests some flexibility when preparing for humidity, with more reason to match conditions for a dry race. But this small male-only lab study doesn’t establish a personal wattage gain, an over-50 response, or an exact plan for your event.

The underlying cooling problem is straightforward. Sweat cools you when it evaporates. Humidity makes that harder. Air movement matters too, which is one reason a sweaty indoor ride is a poor description of the conditions you’ve actually prepared for. The broader heat-training consensus recommends preparing in the competition environment where possible, while protecting training quality.

My coaching takeaway is to start with the event, then decide whether a heat block deserves space in your plan. Don’t add one simply because you can make the trainer room unpleasant. If heat preparation is needed, plan it as training stress, with recovery and an individual progression, rather than another challenge bolted onto an already full week.

What you do with this depends on which rider you are.

If you’re short on time: check the likely conditions at the hours you’ll actually be riding. A cool local event and a hot destination event need different preparation decisions. Keep your limited training time tied to the demands you’ll face.

If you’re over 50: don’t turn the laboratory temperatures into targets to copy. Discuss a suitable progression with your coach, including your health and experience in the heat. The goal is arriving prepared, with the rest of your training intact.

If you’re chasing a result or heading somewhere new: put temperature, humidity and opportunities to cool down on the same planning sheet as the course profile. Arrange heat preparation early enough to learn how you respond, and practise your drinking and cooling routine before race day. That follows the broader IOC guidance for competing in heat.

Prepare for the conditions you’ll ride in, not the sweat you can produce.

Source. McDonald P, John K, Topham T, Sawka MN, Clark B, Périard JD. CrossAcclimation and Endurance Performance Following Adaptation to Dry and Humid Heat. Medicine & Science in Sports & Exercise. Published online 12 October 2026, ahead of print. doi:10.1249/MSS.0000000000004190.

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On my mindLeave room to build

I’ve been thinking about ramp rate: how quickly we build training back up, and how hard it can be to leave a little room when we finally feel good again.

Especially after an injury.

You remember the rides you used to do. You want your normal week back. One encouraging ride can make an extra hour, another interval or a harder group ride feel completely reasonable.

But the week you want to return to isn’t necessarily the week you’re ready to repeat.

That’s the distinction I keep coming back to. Build from what you can currently tolerate, rather than what you remember being able to do. Returning after injury needs a progression agreed with the people guiding your recovery; feeling keen is only one part of the picture.

There isn’t one ramp-rate number that guarantees you won’t get injured. Still, the urge to make up for missed training is worth noticing. It can turn a sensible plan into a much bigger jump without a deliberate decision ever being made.

Sometimes the useful training decision is finishing the ride you planned, even when you feel capable of more. Give yourself the chance to see how you respond before adding the next step.

This week, notice the moment you want to add something just because you’re impatient. You don’t have to act on it.

I’d rather see a few measured weeks of progress than one big week followed by another setback. The long game rewards the training you can keep doing.

— Damian

PS. Want a steady plan for the months ahead? The Winter Block starts on 2 November, with sixteen weeks of structured training for riders 40+, indoors or outdoors, individual feedback on your key session and a small group to train alongside. Enrolment closes when training begins. Join The Winter Block →

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