© Parkrun
Biological men hold at least three Parkrun female records because of its policy that lets entrants self-identify their gender, according to the Policy Exchange think tank.
Gender ideology is risking the fairness and safety of competitions for women and girls, said the analysis backed by the likes of Martina Navratilova and Sharron Davies.
The report also claimed women could be 'alienated' from grassroots sports and highlighted major physical advantages which biological males have over females.
It said Sports England, the Government's non-departmental body for community sport, should tell Parkrun that it must collect participants' data based on biological sex, rather than gender identity, and update course records to reflect this. It added: 'If this does not happen within 12 months, taxpayers' funding should be withdrawn.'
Research by Policy Exchange found at least three female records set at 5km (3-mile) community Parkrun events are held by biological males.
This includes the female 45-49 category at Porthcawl in South Wales which had been set in 2008 at 20.06 minutes by Deb Roberts. In May this year, Siân Longthorpe - a transgender woman who is biological male - set a new record of 18.53 minutes.
Siân Longthorpe - a transgender woman who is biological male - completed the Porthcawl Parkrun in a record 18 minutes and 53 seconds in May in the women's 45-49 age category
The report said: 'Given the fact that men generally have a performance advantage over women of at least 13 per cent, it is unlikely a biological female will beat Longthorpe's time in the future.'
Longthorpe also holds the age 40-44 female record, as well as the outright female record at Parke in Devon, and the female record for ages 40-44 in Torbay Velopark.
Longthorpe is currently ranked 30th on Porthcawl's age-grading leaderboard with an age grade of 84.11 per cent due to self-identifying into the female category.
Parkrun has an age-grading calculator which is broadly based on the World Master Athletics calculator. According to sex, Longthorpe's age grade should be around 74.59 per cent.
Separately, transgender Lauren Jeska who was born a man has held both Aberystwyth's ages 35-39 record and the outright female record since 2012, with a time of 17.38 minutes.
The report said: 'Since 2012, three women have lost out on holding the outright title due to Parkrun's gender self-ID policy.'
Jeska, a former British fell-running champion, was jailed for 18 years at Birmingham Crown Court in 2017 when a dispute over her eligibility to compete as a female athlete despite being born male turned violent.
Transgender athlete Lauren Jeska who was born a man has held both Aberystwyth's ages 35-39 record and the outright female record since 2012, with a time of 17.38 minutes
Jeska, who is still listed on the Parkrun website as Aberystwyth's female record holder, also holds the ages 35-39 record in Cardiff and Parc Bryn Bach in Tredegar.
'They accept funding from Sport England, Parkrun results are published every week on the Power of 10 website and yet when challenged the response is that Parkrun is not a sporting event.
'They can't have it both ways and are alienating women. I am aware that there have been discussions over stopping publishing weekly results and statistics as a way of avoiding addressing the problem, but this again will disadvantage women.'
There are more than 1,000 parkrun events across Britain, with more than 350,000 people taking part each week.
The report said that when registering with Parkrun, runners are asked their gender, rather than sex, and are able to choose 'prefer not to say' and 'another gender identity' aside from male or female.
It added: 'Any male or female is able to enter into any category, therefore they are all mixed sex.'
James Davis, Parkrun's male record holder at Church Mead in Buckinghamshire, said in the report: 'I strongly disagree with parkrun's self-ID policy because it's outrageously unfair to females.
'Males like myself have many physiological advantages over females that allow us to run faster than the equivalent female athlete who is at the same standard.
'For example, my course record is 17:09, the female record on the same course is 19:20, and that advantage is why.'
The report said this table shows the 'scale of male advantage within sports', given that 'every single world record in Track and Field held by a woman has been beaten by a teenage boy'
And it said every British 'long course' swimming record set by an elite female swimmer has been beaten by a teenage boy.
The analysis highlighted concerns about 'gender self-ID', saying it 'fundamentally compromises fair and safe competition for women and girls within grassroots, amateur and elite sport'.
Policy Exchange is now calling on sport governing bodies, the UK Government and the International Olympic Committee to restrict categories for women and girls to biological females at all levels of sport.
Some 99.99 per cent of those taking part in sport and physical activity are not elite or professional, the report points out, meaning that grassroots competitions for females are 'much more likely' to be affected by the issue.
In county athletics championships, the winning male from the slowest county in the 1,500m race in 2023 would have beaten the winning female in 27 out of 33 counties, the think-tank said.
It recommends that the Department for Culture, Media and Sport should require all national governing bodies to update their policies within 12 months to ensure that there is a protected female single-sex category - and that they should lose taxpayer funding if they fail to do so.
Former Olympic swimmer Davies said: 'There is a sense within sports policy that while we should protect the female category within elite sports, women and girls participating and competing at amateur levels should budge over.
'They must 'be kind' and 'inclusive' while having to pretend it is not grossly unfair, demotivating and possibly unsafe to accommodate biological males within their races, teams and sports days.
'Every sport, at every level, from grassroots to elite, must ensure that the female category is ringfenced for biological females.'
Navratilova, the former world No 1 female tennis player and an 18-time grand slam champion, said: 'Female sport must be protected otherwise we risk not only alienating a generation of women, but also taking away dreams and possibilities of fairness and winning for girls and women.'
Daley Thompson, two-time Olympic gold medallist in the decathlon, who also backed the report, said: 'We risk alienating a generation of young female athletes if we cannot promise them fair and safe play from the grassroots level to the top.
'Categories exist to allow everyone the chance to participate, and the willingness to compromise this by policymakers within sport is a scandal.'
A spokesman for Sport England said: 'In 2021, the Sports Council Equality Group published Transgender Inclusion in Domestic Sport Guidance.
'While it is up to sports to set their own rules, we work closely with all organisations we fund to ensure they meet all the agreed criteria and code for sports governance.
'In this challenging and emotive area of policy, we understand and accept that there are a wide range of personal views, and we urge respectful discourse on this matter, and that sports consider their duty of care to all athletes.'
Culture Secretary Lucy Frazer said: 'I agree with the UK Sports Councils who concluded that balancing transgender inclusion, safety and fairness at all times is not possible in every sport.
'Self-identification cannot be reconciled with competitive fairness in every sport.
'Sport must be open to everyone and we are working closely with national governing bodies on a way forward that is compassionate for all, whilst maintaining the integrity of competition.
'While it is for sports to set their own rules we have seen cycling, swimming, athletics, Rugby Union and others take the lead in prioritising fairness at all competitive affiliated events, and I would encourage all sports to look into this issue.'
A Parkrun spokeswoman told MailOnline today: 'First and foremost Parkrun is a health charity. The organisation and our events exist to provide access to free, weekly, physical activity opportunities for as many people as possible.
'We do this in pursuit of improving individual health and wellbeing at scale, with a particular focus on those who might benefit most, including those who don't - and might never - engage with traditional sport and physical activity.
'We do not recognise parkrun as a 'sport' or a 'competition'. Some might consider this to be semantic, however we believe it is a critical distinction and something we have been working hard to communicate over many years.
'Of course how someone chooses to engage with and participate in parkrun is their individual choice. Some will find motivation in 'competing' against themselves and others. But that doesn't define what parkrun is.
'We've recently carried out a period of consultation to ensure that we are doing what is right for Parkrun regarding gender identification. You can read the statement here.
'This consultation included reviewing the UK Sports Councils' Guidance for Transgender Inclusion in Domestic Sport, both independently and with Sport England.
'We are satisfied that, as a health charity delivering non-competitive free to access physical activity events focused on removing barriers to participation, it is right that we continue to prioritise inclusion, enabling us to positively impact the lives of hundreds of thousands of people every single weekend.'
Commenting on the self-ID policy in July, Parkrun's chief executive Russ Jefferys said on X: 'I have absolute confidence in our current policy. Doesn't mean we're not listening and engaging, but I'm totally comfortable with our current position.'
At the same time, Parkrun communications chief Kirsty Woodbridge said in a blog post: 'We aim to be as inclusive and welcoming as possible, and whilst there is and possibly always will be discussion around how we record and present people's identities, we believe that our current solution is the most appropriate available at this time.'
Comment: Is it the most appropriate solution because they fear the backlash from the woke left?