Adam Jones prepares for Cardiff Half Marathon after five-stone weight loss

Former Wales prop Adam Jones is preparing to run the Cardiff Half Marathon on Sunday 4 October after losing five stone, a change he says began when he decided to challenge himself beyond rugby. The 45-year-old Harlequins scrum coach has completed a 17-kilometre training run and says his main aim is to get around the course. He is running in aid of St David’s Hospice Care and Prostate Cymru.

Jones told BBC Sport Wales that he weighed 24 st 7 lb (156 kg) while working with the Wales coaching staff in Japan in 2025. He said he recently weighed 19 st 7 lb (124 kg). Those stated weights are five stone apart. Seeing footage of himself during the Japan trip, along with experiencing gout, prompted him to make a change, he said.

From short intervals to 17 kilometres

Jones said he began with a couch-to-5K approach, starting with walking and brief running intervals. His first session involved a five-minute walk followed by a 90-second run. Reaching five kilometres gave him a sense of achievement, and he began considering a longer event. He initially thought about a 10K before deciding there was enough time to prepare for the Cardiff race.

He described the process to the BBC as gradual. Jones said he has been training every day in one form or another and changed his diet, including cutting out chocolate and bread. He contrasted that approach with the crash dieting he said he sometimes used as a player when trying to reach a required weight before a match. His account describes his own preparation; it is not a training prescription for other runners.

Why Jones took on the race

Jones said he wanted a challenge that would take him out of his comfort zone. He also connected the decision to his coaching role: he asks Harlequins players to keep working when training becomes difficult, and felt they should see him make a comparable effort. He said players and coaches at the club have been supportive, with some sponsoring his run.

The former prop played 95 internationals for Wales and five Tests for the British and Irish Lions, according to the BBC. He was part of Wales teams that won Grand Slams in 2005, 2008 and 2012. Jones joined Harlequins as a player in 2015, retired in 2018 and moved into coaching. He also worked temporarily with the Wales coaching staff in 2025.

Jones has set no firm finishing-time target. ‘It’s more about getting around for me,’ he told the BBC. He said Harlequins player Cadan Murley had offered to double his contribution if Jones finished in under two hours and 30 minutes, but Jones did not present that as his goal. He expects his wife Nicole and daughter Isla to support him on the course.

What awaits in Cardiff

The race organiser’s event guide says the Cardiff Half Marathon will start on Castle Street at 10 a.m. on 4 October, following an elite wheelchair start at 9:57 a.m. This will be the event’s 23rd edition. More than 30,000 places have been sold across the weekend’s events, including junior races on Saturday and the half marathon on Sunday. The organiser says entries are sold out and there will be no places available on the day.

The route starts outside Cardiff Castle, passes the Principality and Cardiff City stadiums and heads through Penarth Marina and Cardiff Bay. Runners then loop around Roath Park lake before finishing in the civic centre. The organiser says road closures will be in place on race morning and advises participants and spectators to plan their journeys ahead. Jones told the BBC he hopes support from the Cardiff crowd will help him through the final miles.

Jones said he was nervous but excited after receiving his race number. He has spoken about possibly attempting another half marathon, while making clear that he wants to see how this one goes first. His finishing time, whether he completes the race and the amount raised for the two charities will only be known after the event.