You were built to run in the heat.

Of all the conditions a marathon can throw at you, heat is the one you were built for. Two million years on the African savannah shaped the human body for exactly this: persistence hunting — running prey to collapse under a midday sun no other predator would step into.

Look at what we carry from it. Millions of sweat glands, more than almost any animal alive — a cooling system that runs while we run. Bare skin instead of fur, so the sweat actually cools us. An upright body that offers only the head and shoulders to a sun beating straight down, where a four-legged animal bakes along its whole back. And the rare ability to drink on the move. Nothing on earth is better built to run in the heat than a human being.

That does not make a hot marathon easy. It means the work is to wake a birthright that modern, air-conditioned life lets go dormant — to remind the body of what it already knows how to do. That is exactly what the four modalities are for.

When the heat turns dangerous, swimming is the modality that does not care. The pool is the climate-proof engine — full aerobic stimulus with the water carrying your heat away as fast as you make it. On the days it is too hot to run safely, the engine still grows. It is the same escape hatch as the dead of winter, at the opposite extreme.

Better still is the pairing. Run in the heat while it is bearable, then move straight to the pool: keep the aerobic work going, wash off the sun, and finish a long session cool and fresh instead of cooked. The run-into-swim is one of the best dual sessions in the method, and a hot summer is when it earns its keep.

Yoga was born in the heat of India, and it has always been a sweating practice. Held postures and steady breath raise your core temperature from the inside — the body learns to cool itself, to keep working as the heat climbs, to stay calm while it sweats. That is heat acclimation, the single biggest adaptation that makes a hot race feel easier, trained on the mat.

And the heat repays the practice. A warm body moves further into every shape; the same internal heat that acclimates you also primes the tissues for the mobility work, so range comes easier and goes deeper. In the heat, yoga gives twice.

Heat is the season to get the kettlebell out of the gym. There is no reason to lift in a hot, stale indoor room when the bell is just as happy in a garden or a park. Train in the sun, in the open air, the way the body likes to work.

And the warm weather hands you a warm-up for almost nothing. Muscles that are already warm are ready sooner and move better; the heat does the prep you would otherwise have to earn. A summer of outdoor kettlebell work is strength training with the conditions on your side.

Being built for heat is not the same as being immune to it. Two things still decide a hot race, and neither is unique to our method — we just say them plainly.

Hydration. You lose fluid and salt faster than you can feel, and once you fall behind you do not catch up mid-race. Drink to a plan, salt to a plan, and rehearse it in training so race day is practised, not improvised.

Pacing. Heat raises the cost of every mile, so the honest pace is slower. Run the effort, not the number, and start conservative. The runner who respects the heat early is the one still running it down at the end.

A hot race is usually a hot build, too — the autumn majors are trained through high summer. Tell the app your race date and it accounts for the season you will train in: the heat exposure that acclimates you, the pool waiting for the days it is too hot to run, the outdoor strength, the hydration you will rehearse.

You were built for this. The app just helps you remember how. The same method, built around the race in front of you.