G o to any preppy part of London and you’ll see them: Hoka trainers pounding the pavement, Lululemon shorts blowing in the breeze, Salomon running vests bobbing in unison as hoards of under 30s log their latest run on booming fitness app Strava, alongside a sweat-sheened selfie. You can’t miss them. In fact, of the 1.1million people that have entered the ballot for the 2026 London Marathon next April, more than a third of UK entries are between 18-29-years-old. For many young people, the itch to pound the pavement formed in the first Covid-19 lockdown spurned on by the “Run for Heroes” campaign that saw hundreds of thousands of people run five kilometers, donate £5 to the NHS and challenge five friends to join in. It raised over £7m. What kept us running, though, myself included, was fear. I’d recently graduated, had no job, and the world had succumbed to a deadly virus. Nothing was in my hands – other than how many kilometers I rallied myself into jogging each day and what time I got up to do them.…