The reports she has stockpiled, but not looked at, since winning the 1992 Olympic title are likely to deepen the realisation of all she has done in a career which ends at Gateshead tomorrow.
"It is just starting to sink in now," said the 31-year-old who, just three years ago, held the Olympic, world, Commonwealth and European titles at 400 metres hurdles, as well as the world record.
Her decision to retire - taken in Athens last month when a calf injury ended her ambitions of regaining her world title - came shortly after a similar announcement from Britain's other Olympic champion of 1992, Linford Christie.
Christie's first reaction on hearing the news was one of disbelief. "She's got years still ahead of her," he said.
True enough. But Gunnell has decided that they no longer need to be years given up to the spartan dedication of the world class athlete.
"Linford had a total passion for running," she said. "But as I said to him at the time, I didn't have the motivation to win any more. I didn't think I could go out and train for another year."
The strain of recovering from two traumatic injuries to her Achilles tendons had plundered her resources. And when her rising hopes and returning confidence were crushed down by yet another injury last month, she knew what she had to do.
"It's funny really," she said. "But in January 1995 I was frighteningly fit - fitter than I had ever been. My goal was to break the world record again, and I think I pushed it a little bit too hard. After 1995, I was always having to play catch-up.
"When I made my decision I felt an enormous sense of relief, as if something had been lifted from my shoulders. Now," she added, hunching her shoulders and rubbing her hands briskly together, "it feels like a new beginning."
She has, however, one remaining fixture to honour - a 200m relay in tomorrow's Bupa Grand Prix. Thereafter she is free - or relatively so. She still has endorsement deals with, among others, Mizuno sports shoes and Berlei bras.
She is lending her name to Fit Stop gym company, an organisation which plans to open a number of clubs around the country in the next three years. There are plans, too, to extend the start she made in television when she presented the series Body Heat. Other projects are also likely to divert her. As she said of her husband in Athens - "The pressure is all on him now. He's got to support me and get me pregnant."
For the moment, though, Gunnell is preparing for the potentially difficult occasion of saying goodbye to a sport which has occupied a central position in her life for 15 years. "It will feel strange to run my last race," she said. "It is bound to be a huge emotional thing for me. I'm not sure how I will feel on Monday."
Her farewell comes at the end of a week in which she, along with millions of others, has been deeply upset by the death of Princess Diana. The hotel in which she spoke yesterday was next to Kensington Palace, with a view of the flowers and cards wedged into the railings. She had brought her own posy of flowers up from her farmhouse on the edge of the South Downs to lay in tribute.
"It was an absolute shock when I heard the news," she said. "Diana was the only one of the Royals I hadn't met, but she was the one I wanted to meet out of all of them, really."
Three months before Diana's visit to Angola to publicise the campaign to ban land mines, Gunnell had made a similar visit - also at the request of the Red Cross. "It was amazing watching her documentary of the visit the other night," Gunnell said. "I recognised all the places and people she met."
The Angolan trip was not without dangers. But Gunnell's fears concern something nearer home - a horse called Eric.
She and her husband own a half stake in Eric, a highly promising showjumper, the other half belonging to its rider, Chris Ellis.
Gunnell's Olympic ambitions have been transferred to a four-legged runner - the dream is to get Eric to Sydney in 2000.
"Training horses is not a million miles away from training athletes," she said. "You have to prepare them very carefully."
Gunnell of all people is aware of the potential dangers of over-training. Eric is currently resting for three months in a field.
The next competitive decision facing Gunnell will be whether to follow her husband into showjumping. "He is already competing at some smaller meetings on his horse, Corky. It freaks me out a little bit when I see him jumping. I'm not sure I've got the bottle for that. But maybe I'll feel the competitive urge in six months' time."Reuse content