The weather presenter was rushed to Wexham Park hospital in May last year after being knocked over by a car in Slough, Berkshire.
She consequently had to take three weeks off work to recover.
Speaking on the Her Spirit podcast, Kirkwood got emotional as she told Louise Minchin and Annie Emmerson about the experience, and how she became hesitant to get back on the road.
“I’ll never forget that accident, it was horrific,” she said. “My knee was absolutely battered and there were nerves apparently hanging out of it. There was so much blood. It was cut all the way down to my knee cap.
“Fortunately, my knee cap was okay… bruises all over my body but you get over that kind of thing. But sometimes I’ll dream about it and still hear that [crunch] of the car hitting the back of my bike…”
Kirkwood then became distressed and upset from the memory before telling the hosts: “Oh my goodness, I can’t really talk about it…”
She also explained that she was saved by her bike helmet, which prevented her from “faceplanting” the floor, but her nose was left badly bruised.
Kirkwood has not spoken about the incident since the crash, or the severity of her injuries.
At the time, she simply tweeted a vague description of what happened to thank the ambulance team and the fellow cyclists that helped her at the time.
“Been off following an accident. Got knocked off my bike by a car and got injured,” she wrote on Twitter.
“Biggest thanks ever to the Police (Chris and Faye), the Ambulance Crew (Miranda and Stewart) who tended to me and took me to Hospital. And especially Peter Foskett-Tharby at Wexham Park Hospital.”
“I am overwhelmed and humbled by all your lovely tweets,” she later added after her return to the BBC Breakfast studio.
“Will read them properly when I get home later. THANK YOU! It is so good to be back. Hope you are all keeping well.”
She also told the podcast she is yet to get back into riding, but hopes to get back on her bike one day.
Watch: BBC Breakfast's Carol Kirkwood makes funny slip up