The prison has a well-equipped gym and sports hall to encourage inmates to look after their health through fitness.

And Jamie Field, who plays for Featherstone Rovers, teamed up with pal Mark Field, former Wakefield Wildcats player now with Dewsbury Rams, to give a team of prisoners a gruelling training session in the sports hall.

Jamie said: "One of the prison officers trains at my gym - Five Star Fitness in Castleford - and he said some of the lads might like a session, so we thought we would come in and give them one."

One in five of Armley's 1,000 prisoners regularly uses the gym.

Jamie said: "If they are doing training it gives them something to do and helps keep them motivated for when they go out. Giving them an interest in something like weights can only be for the good."

Mark works as a personal fitness trainer at Jamie's gym, which Jamie runs with Huddersfield Giants player Ryan Hudson.

"We thought it would be nice to do something different for these guys," he said.

The session included one-to-one pad punching - a form of boxing training - with the two players.

Prisoner Kev Wiltshire, who works as a gym orderly at the prison, said: "It's brilliant. It's really good for fitness. I work out every day."

Another gym orderly, prisoner Neil Holmes said: "They definitely get a lot out of it. It takes a bit of the stress out of people, even if it is just a weight session.

"Some people come down stressed and go back feeling great."

Prison physical education officer Steve Booth said: "Some of these lads would be down here two or three times a day if they could. Prisoners who work get three or four sessions a week, unemployed prisoners twice a week.

"The idea is if they are working they get to use the gym on a weekend and in the evenings."

Prison jobs include kitchen work, cleaning, education and a number of workshops including tailoring, and jobs in the prison hospital.