Fit in my 40s: an ice bath feels great (once the agony wears off)

The ice bath found its modern pioneer in a man called Wim Hof. An inspiringly beardy gentleman with 1.9 million followers on Instagram, he proselytises cold exposure as part of a suite of self-improving exercises; yoga and mindfulness among them. But it’s the ice that he’s known for, because he’s just so rock-hard, and often nearly naked, in situations where you’d want not just regular clothes but also long johns and probably a big winter coat, too.

Martin Petrus, a breathwork coach and author of the Cold Exposure Guide, described to me how to dunk yourself into this enterprise. The problem with incredibly cold water is that every synapse of your sorry mind urges you not to enter, whatever the benefits. “The best way is to go very slowly, and progress only when you feel ready,” he says.

Before we get to the “how?”, let’s do the “why?”. At the most general level, cold water puts you under hormetic (or low dose) stress; if carefully managed, with planned recoveries, this is beneficial for the same reasons that intermittent fasting and repetitive weight training can be good. If exercise damages your muscle fibres and they build back stronger and bigger, cold does the same to your synapses.

According to a Cambridge University study published in the journal Nature in 2015, a cold shock protein found in hibernating mice reduced the loss of synapses – the connections between cells in the brain. The report’s author, Prof Giovanna Mallucci, at the UK Dementia Research Institute, recently studied cold-water swimmers, and showed that cold-water immersion could slow the onset of dementia.

It also works against inflammation. I realise people say that about everything, from turmeric to sex (don’t multitask on these), but there is bona fide evidence to show that both hormones and proteins that inhibit inflammation are boosted by systematic and regular cold-water immersion. Inflammation is a useful short-term immune response, but it will wreck your body if it strikes for too long, or too often.

You can get into this game gently – there’s no such thing as not cold enough, in water terms: there’s a distinction between the cold bath (10-14C), the chilled bath (5-9C) and the ice bath (0-4C). Even if you’re at the upper reaches of the range, and staying in for only one minute, that will still contribute to your endurance for the next time, and bring the shock benefits your body craves. I tried a bath first, and didn’t get along with it. I made so many whiny noises just getting one leg in (it wasn’t even super iced, just chilled) that the dog started whining outside the door. The shower, on the other hand – turn it to cold and promise yourself you’ll do no more than 10 seconds. There’s still a lot of sharp-breath intaking, but anyone can manage 10 seconds of anything, give or take. Up it by a second every day. I’m currently stalled at 20 seconds, but each time I feel exhilarated, galvanised, a little bit up myself.