2014 was a golden year for Jo Pavey, crowned by winning the European 10,000m title in Zurich at 40. Only 10 months earlier she had given birth to her daughter Emily.
She is quite the inspirational woman.
But as she pounds the roads near her home in Devon preparing for a new season, it's not just the long training sessions occupying Pavey's mind. She's getting increasingly troubled by the rumours circulating athletics about the hormone-replacement medication thyroxine.
It is not outlawed but in her view it is very definitely unethical, if taken by those who don’t clinically need it. What’s more, those rumours suggest its use among elite athletes in Britain and beyond is not uncommon.
In short, Pavey wants it investigated.
Synthetic thyroxine is replacement medication for those who suffer from an underactive thyroid gland.
Many believe that for the athlete who doesn’t clinically need it, it can aid recovery from heavy training sessions and also, because of its effect on the body's metabolism, it assists weight loss. For endurance sport you can see the potential benefits.
Thyroxine isn’t a banned substance, but that's not for the lack of trying. UK Anti-Doping (UKAD) along with some of its like-minded foreign counterparts recommended to the World Anti-Doping Agency (WADA) that it should be on the prohibited list. That's because UKAD firmly believes it is a performance enhancer, it is potentially a risk to health, and it is against the ‘spirit of sport’; in other words it’s unethical.
WADA, so far, have only noted UKAD’s concerns but are not actively investigating it. They do have limited resources and, while pawing over allegations of systematic doping in Russian athletics, their hands are quite full. They also tend to engage in doping wars they think they can win.
UK Athletics' policy on thyroxine replacement medicine is clear: "there are no grey areas". If an athlete requires it because of an existing thyroid condition then with a doctor's exemption form, that is of course acceptable. But if an athlete is using it to help recovery or performance then that falls outside their guidelines.
A recent statement read: "British Athletics always apply the highest standards to medical practice. Thyroxine is only ever prescribed when treating hypothyroidism and we have worked closely with the EIS, UK Anti-Doping and the British Thyroid Association to ensure good clinical governance."
The "grey area" is the argument that, if an athlete's thyroid function is temporarily suppressed by overexertion, then using a hormone replacement simply brings the body back to function at its pre-exercise levels, albeit artificially - not unlike an iron supplement does for iron deficiency.
Those who counter that view say the imbalance is caused naturally, through exhaustion, and that is a by-product of what an athlete does, so to alter that balance is ethically questionable.
That is Jo Pavey’s very firmly held view.
She adds: “That's part of training and anything I think which is unnaturally making your body deal with the training, increase your metabolism, make you be able to train harder, I believe that's unethical and it shouldn't be something we think 'oh that's fine'.”
While UK Athletics team doctors do test thyroid levels when they monitor athletes' health under their care, during international championships for example, their investigations would not necessarily detect thyroxine usage.
UKA points out that the prevalence of those athletes who are legitimately using it falls inside the average for the general population over that age range. But if an athlete wanted to hide it, it's possible, and it is much easier, and of course less risky, than concealing steroid use, for example.
Pavey had a blood test in the summer before the European Championships and was informed by a doctor that the results revealed she had slightly irregular thyroid levels. It was suggested to her that she considered investigating whether hormone replacement was right for her. She was outraged.
It is perhaps fitting then that she went onto become one of the stories of last summer with her gold medal just a few weeks later.
Pavey’s reputation is almost as important as her achievements.
"I feel particularly protective that people think 'how's she running like that at the age of 40?' I've prided myself as being a clean athlete my whole career”.
It is a common complaint among clean athletes that cheats give them all a bad name.
The generally accepted medical guidelines are that Thyroid replacement should only be prescribed if thyroid levels are detected to be consistently at unnatural levels over a period of time, maybe a few months, but not usually after a single test.
Dr Jake Powrie is a consultant who specialises in thyroid disease and is also an adviser to UKAD. His personal opinion is that Thyroxine should be on the banned list. Whether it does or doesn’t have performance-enhancing qualities is now almost irrelevant, he says, because of the strong rumours swirling around.
Those effects could include severe weight-loss, muscle wasting and in extreme cases even osteoporosis, the so-called brittle bone disease.
However, I have spoken to one team Doctor who looks after many elite British sportsmen and women, Olympic medalists among them, who believes that as long as Thyroxine is not prohibited, its use is legitimate.
And to further illustrate the sensitivity over this drug, one high-profile and outspoken anti-doping British athlete we contacted did not want to talk about Thyroxine.
“It’s a really grey area...I don’t really wish to comment on,” they said.
But then we have already established in UKA’s opinion there is actually no grey area at all.
So perhaps this response is the most revealing – a hardened anti-doping campaigner, reluctant to give an opinion about this particular medication.
Jo Pavey has been brave in speaking out about this. Athletics does not like controversy and does not like one of its own spreading negativity.
That is not Pavey’s intention; she actually believes her sport is cleaner than it’s been for some time and her great success last year she says is perhaps evidence of that.
In the background she says her concerns are supported by many others in the UK and abroad. It is understandable perhaps that some of those others, at the beginning of their careers, feel less confident about voicing their disappointment.
Pavey wants her views to ignite an open conversation and her sport owes it to her to listen.
In a world where Nike, one of the biggest and richest names in track and field are happy to drop an inspirational role model like Pavey but pay the big bucks for a doping recidivist like Justin Gatlin, then in reality, if we care about clean sport, we should listen too.