Four years on, MacLarty is the first to admit that she hasn't made the progress most predicted. There are extenuating factors, significant ones, but more on those in a moment. As of today, the future looks decidedly rosy again – and that has much to do with McColgan. Now, coming together in what might be called Scottish athletics' dream team, MacLarty has been taken on by McColgan, with the former world 10,000 metres champion-turned-coach admitting she is "extremely excited" by her protégé's potential.

She isn't the only one. Indeed, MacLarty's excitement is such that it has been a factor in her making a major, life-altering decision. After wrestling with the dilemma for months, and having recently completed five years of medical studies at Dundee University, she decided this week not to pursue a career in medicine. Her desire to fulfil her potential as an athlete is a major reason, though not the only one. Another is McColgan's enthusiasm at the prospect of, as MacLarty puts it, "getting hold of me".

"I approached Liz initially," says MacLarty, "to ask if I could join her training group. She said that if I joined the group then she wanted full control. For the last couple of years I was in no-man's land, living and studying in Dundee, and going home to my training group in Stirling and my coach (Derek Easton]. I've been with Derek since I switched from football (MacLarty was an age-group internationalist] seven years ago, and I was more nervous about speaking to him than I was for my final exam. But Derek was really good, really supportive."

The decision wasn't easy, though. Indeed, MacLarty – who might sometimes be too intelligent and thoughtful, and certainly too nice, for her own good – was racked with feelings of guilt. "It was really upsetting. Speaking to Liz about working with her… it felt like I was cheating on someone who's really supported me and helped me."

She agonised, too, over what to do on finishing her medical degree. Although there is a healthy tradition of medics doubling up as top athletes – most famously Roger Bannister; more recently Curtis Robb – it isn't easy in the modern, non-amateur era. As she has juggled studies with training, MacLarty's progress has been hindered by a succession of injuries and illnesses, which some believe to be related to her over-stretching herself, and the impossibility of fitting everything in.

Having finished her studies, MacLarty was, until this week, contemplating two years working long hours, including night shifts, as a junior doctor. The prospect concerned her, and would almost certainly have signalled the end of her career as a top-class athlete. She enquired about working part-time. She asked about taking some time out. She understood that in "special circumstances" her terms of employment could be more flexible. But each request was met with a polite refusal. It seems a little ironic that an organisation devoted to health and well-being should prove so intransigent, and fail to support one of the country's top young sports people, though MacLarty, characteristically, says she fully understands why she wasn't deemed worthy of special treatment.

But it left her with a straight, if difficult, choice: medicine or athletics. "I haven't been sure about medicine for a while," she admits. "I love the practical procedures but there are things I don't like and I just wasn't sure any more."

McColgan has an interesting take on this: "She's a very intelligent girl who I think has been pushed into medicine through exam results rather than through a real desire to be a doctor. When I first sat down with her I said that medicine isn't just a job, it's a vocation – like athletics. I was happy to help her train around her foundation training, though I knew it wouldn't be easy; but then she told me she wasn't sure that she wanted to be a doctor. Ultimately, it was a decision she made herself."

"It feels like I've been carrying this massive weight around my neck the last few months," says MacLarty. "I just felt so uncertain about everything. Then I started talking to Liz and she was saying really exciting things. I just feel that with (the] 2014 (Commonwealth Games in Glasgow] coming up, I'd love the opportunity to compete there. So I've made the decision, and my parents have been amazing about it."

McColgan stresses that time is of the essence, and adds that her new pupil can't afford any more setbacks. "She's one of the most talented athletes in Scotland. She recently ran 2.09 (for 800m] off nothing, so the talent is still there, but it's now or never for her.

"When she approached me, in May, I said she either worked with me full-time or not at all," continues McColgan. "It doesn't work having a foot in different camps; she's been stretching herself every way but the right way. It was putting her under a lot of pressure and she got very ill after the (2006] Commonwealth Games. I'm also sure that all her niggly injuries are because of the pressure she's put herself under. She's only human, and sitting up studying till 2am isn't conducive to being an athlete. I want to take that pressure off her, and I deal with the whole package – nutrition, strength and conditioning, lifestyle."

McColgan says she has a two-year plan for MacLarty, which could see her approaching her best at the 2010 Commonwealth Games in Delhi. "But we're looking at London 2012, Glasgow 2014 – she can be challenging there," says McColgan.

The priority for MacLarty is to recover from her latest injury, a chronic hamstring complaint, while weighing up her options away from the athletics track. She fancies dentistry, pointing out that "I couldn't just do athletics – I need something else to focus on."

Already she has been impressed by McColgan's ability to impart her vast knowledge. She couldn't have a better teacher, though she adds that "I didn't really have any athletics heroes – I was more into football growing up. But Liz is an inspiration, and so many people remember her gold medal at the (1986] Edinburgh Commonwealth Games."

That was a big year for MacLarty, too. In a neat piece of synchronicity, her new mentor's major breakthrough came in the year that she was born.