Former Whitehaven captain Marc Shackley has been banned from all sport for four years, following a positive reading for a banned substance in a urine sample.
The UK Anti-Doping test taken in September 2021 showed trace of clenbuterol, an anabolic agent.
Shackley, now 33, retired that month because of a knee injury and said he had taken a fat burner containing the agent to slim for surgery on the joint.
He could not prove the violations were unintentional and the ban was imposed.
Shackley also stated he had already retired before the test and a subsequent anti-doping rule violation had been picked up in an out-of-competition test.
However, an independent panel ruled UKAD had jurisdiction on the violation, and Shackley could not prove he did not know of the presence of clenbuterol, which was his secondary position.
The ban he has received is backdated to 8 October 2021, and will expire at midnight on 8 October 2025.
He scored 26 tries in 236 games for Cumbrian sides Workington and Whitehaven.
“Athletes are solely responsible for what they put in their bodies at all times and should always check their supplements and medications on Informed Sport and Global DRO before taking them,” UKAD director of operations Pat Myhill said.
“The rules are clear and athletes have a responsibility to protect their own health, career and their sport.”
The Rugby Football League’s director of operations and legal Robert Hicks added: “This is a case which reinforces the responsibility of players to take the steps to reduce the risk of failing a doping violation by checking their supplements.”
