“We assess every client individually,” he says. “We had one 83-year-old woman who moved into Auriens who had never been to a gym before. She had very high cellular stress and was essentially immobile. We started her with walking and Pilates and within two weeks we could see a difference and so could move onto harder exercises.”

Sometimes he also finds himself battling against doctor’s advice, noting that he had one 75-year-old client who had been banned by medical professionals from playing tennis again because of a bad back. “I did a good physio and stretching programme and he was back on the courts in two weeks. There’s a lot of misinformation out there that leaves older people wary of hurting themselves, when actually stopping a sport they enjoy is far more harmful.”

Equally, more time gives older gym members an advantage over younger working adults who can just squeeze in a 30-minute class before work or picking the children up from school – and is why they often become star performers in classes such as Pilates that are all about commitment rather than youthful energy. “For me, the key difference with the over-60s is that they have so much more time,” says Heagney. “The goals stay the same but the pace they set out to achieve them changes.”

As for why it is that older clients are paying more attention to their health than ever before – both men agree that much of this is to do with the pandemic, and the fact that most people of retirement age have felt more vulnerable over the last two years. Exercise feels like one way of getting some control back.

And for those of us who can’t afford six-figure tailored exercise programmes? Try exercises that focus on strength training and weight lifting. “Active ageing is all about strength,” says Remfry. “The more muscle you have, the stronger you will be – there are mitochondria in skeletal muscle cells that honestly are the elixir for healthy ageing.”

And – it turns out – an elixir you don’t even need to be a millionaire to get hold of.