Cancer campaigner Jane Tomlinson said she "ran her heart out" to complete the New York marathon and kick off her campaign to raise another £1m.
Jane Tomlinson completed the New York marathon in five hours.
Mrs Tomlinson, who has the illness, was speaking in New York after completing the course after only 12 weeks training due to chemotherapy and injury.
Mrs Tomlinson, 41, of Rothwell, Leeds, beat husband Mike for the first time, asking him: "Are you all right?"
The mother-of-three had previously said she was retiring from charity work.
But following a course of chemotherapy earlier this year, her health stabilised and she has decided to continue fundraising while she is still able.
"It was a long, hard day but it was fantastic," she said, adding she completed the course in five hours 15 minutes.
"The course was very hard and it was quite hot, but I overtook Mike for the first time.
"The atmosphere as we went round was really good - it's a great event.
Since being diagnosed with terminal cancer five years ago, Jane has not only taken part in the Florida Ironman, one of the most demanding athletic events in the world, she has also completed a 2,500-mile bike ride from Rome to Leeds as well as a number of triathlons.
So far Mrs Tomlinson has raised £1.2m for the cancer charity she set up four years ago. But she hopes to add another £1m to the total in a final year of fund raising.
"The is the first event of this new year of fundraising and it was really fantastic," she said.
"I'm going to go and get some rest. I'm not thinking about the next thing just yet. I'll get my breath back first."
She announced last month that she plans to take part in a series of events over the coming year culminating in her most ambitious event to date, details of which are expected to be announced after Christmas.