Heat training left me thinking 'if that’s what Hell is like, it would be easier to be good'

Last spring I found myself in urgent need of a training shortcut. I had decided to do the National 24-hour Time Trial Championships, and was a bit short of fitness and rather unwilling to solve this problem using the traditional method. What I wanted was an easier way.

Michael Hutchinson

Michael Hutchinson is a writer, journalist and former professional cyclist. His Dr Hutch columns appears in every issue of Cycling Weekly magazine. 

Luckily, I’d been doing some reading about heat conditioning. The conventional use for heat conditioning would be preparing to race in a very hot place – a long time ago I did some heat work to prepare for a race in Delhi in 40-odd degrees, and it was quite effective.

More recent studies have suggested that training in hot conditions can have benefits for racing in normal temperatures, a bit like altitude training. It supposedly increases your blood plasma volume, which increases your VO2 max. There are other touted adaptations, which I’m a bit more doubtful about, but, like magic pixie training dust, you can’t actually prove that they don’t work.

I ignored one well-put-together study that concluded the whole thing was hokum. I ignored it and did my best to forget it, because there is such a thing as the placebo effect, and it’s well known that reading too many scientific papers can seriously undermine it.

The other thing that’s attractive about heat training is that it doesn’t take too long. 45-minutes a session is plenty. And perhaps as few as four or five sessions in total over a month is all you need. If it’s hokum, at least it’s fast-acting hokum, and that’s the best sort.

The protocol is simple. You warm up your environmental chamber / shed with a couple of heaters. You introduce some steam to get the humidity up – I favour a wallpaper stripper. When it’s over 35 degrees, and above 80% humidity, you get on the turbo trainer.

Typically I started out with a pulse of 130 and a power output of 270. After 45 minutes, these numbers got closer than I liked to reversing – 170 bpm and 130 watts. The session is short, but it is miles from easy. You have to deal with the dissonance of riding quite hard, at an objective effort level that’s barely “recovery”. And you sweat grotesquely, like a blob of mozzarella in bike shorts.

Go too hard and you get worryingly hot. For reasons of not killing myself, I literally won’t do a heat session if I’m alone in the house, because on my first attempt back in 2010 the shed drifted up to over 40 degrees. I overheated and had to lie in the garden while Mrs. Doc sprayed me with a hose as if I were a stranded dolphin.

This time, a physiologist friend said, “There’s a way to make the session more effective for no extra riding time; sit in a warm bath for half an hour when you get off. It keeps the stimulus going.”

Let me tell you, nothing in history has ever sounded so good and turned out so bad. You get off the bike very hot. You desperately want to cool down. So you go and sit in a “relaxing” bath and just stay hot. The sensation is hard to describe – it’s like your body has forgotten how to cool down, and you’ll be hot forever. It’s not even like the bath is that warm – it should be only a couple of degrees above body temperature, yet you feel like you’re being slowly boiled alive.

I sat there for half an hour, and the only thing I could think was that if that’s what Hell is like, it would be easier to be good.

I have, of course, absolutely no idea if it worked.

(If you still want to try it, be careful. Work the temperature up gradually over a couple of sessions, stay hydrated, and stop if you need to. And definitely don’t make the bath too warm.)