Amongst Radcliffe's many marathon wins are three London Marathons, and she held the record for fastest female marathoner of all time for 16 years.
Wright is running this year's event as his first marathon, but told OK! he had left nothing to chance by signing up expert Radcliffe for advice.
He said: "You can't really beat it, can you? She’s incredible. When you're training for something like this, you always take advice on Google or people you know who have done it, everyone gives you different advice, but I just stuck with her expertise and advice.
"And of course, it was the best. Because she's the best of all time."
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Former Towie star Wright was originally signed up to run last year's London Marathon, but had to drop out because of injury and move his place to this year's race.
He began working with Radcliffe two years ago, to prepare for the race he should have run, and shared that she had been helping him with his recovery, too.
The Heart radio presenter, who also runs a fitness business with his brother and is a former footballer, said it was "an honour" to train with Radcliffe.
Radcliffe said that she was impressed with Wright's running abilities, saying he has handled the training "really well".
She added: "I think he would say he probably didn't see himself as a marathon runner in the beginning. He was quicker with the shorter distances and I think coming from football as well, that kind of made that side easier. But he's probably surprised himself."
The London Marathon takes place on Sunday, with the 2023 race ballot opening today - the first one to take place in its usual April slot since 2019.