A post on Twitter by five-time British time trial champion Alex Dowsett in which he related how he had to swerve yesterday to avoid being hit head-on by a speeding Porsche Cayenne driver who was overtaking another car has resulted in hundreds of his followers sharing their own experience of similar incidents with him.

The post by the 27-year-old Movistar rider, who will be riding for Katusha-Alpecin next season, has been retweeted more than 4,000 times on the social network.

Dowsett wrote: “Today a new red Porsche Cayenne overtook another car but in doing so he came straight at me on my side of the road doing, I would guess (given it was an overtake in a powerful car) around 60-80mph. I was doing 25mph. A head-on at this speed is an impact speed of 85-1005mph with a 2040kg car and an 80kg me… you can do the consequential maths.”

He continued: “He saw me, we made eye contact, I don’t know if he saw me before he started the overtake but once he was mid-manoeuvre he saw me, he didn’t try to squeeze the Fiat 500 he was overtaking, nor did he tray and brake or even lift off and I’m fairly sure of this, he took a chance that we would all fit.

“Of course, I was angry initially, in shock that someone could take such a chance with someone else’s life for the sake of an overtake.”

He added: “I was in tears afterwards. It’s the closest I’ve ever been to a career or life-ending crash and it’s scared the living daylights out of me, made me question why we do what we do and if the consequences are worth it.”

Dowsett, who said that as of today he will ride with a camera fixed to his bike, ended his post with a message for the driver of the Porsche Cayenne.

He said: “If you get the chance to read this, I hope you had a fright also, I hope my thoughts of what my loved ones would do if I didn’t come home from a training ride mirrored the thoughts of how your loved ones would be having to visit you in a cell, or how you’d feel with the guilt you’d carry, and so I really hope it’s something you won’t do again.”

His post has received more than 300 replies, including this one from James Hayden, winner of this year’s fifth edition of the Transcontinental Race.

A number of people questioned whether Essex Police would do anything even if presented with footage of the incident, given the video that emerged over the weekend showing a cyclist in the county being deliberately knocked off his bike and assaulted by a motorist, against whom no charges were brought.

Former British road champion Brian Smith spoke of two recent incidents that had happened to him.

Dozens upon dozens of ordinary, everyday cyclists shared their stories too, leading Jason Bradbury of The Gadget Show, who has also presented The Tour Series on TV, to make this observation.