Speaking on the challenge, Alex said: "I'm not built for biking, I don't like riding or running and really cannot think of anything worse than riding to Wembley. I have been asked to take this challenge on and to be honest im scared.
"I will always support charity especially RL Cares as for me it is the key charity in Rugby League. They are there for past and present players to support, assist and deliver services that help players deal with what ever issue they face.
"Allot of the amazing work they do daily remains anonymous due to the delicate and personal situations that they support players through. As well as difficult issues they offer educational support and assistance with the difficult time of transition when a players career comes to an end.
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Warrington legend Ben Westwood caught up with JJB on his 400th appearance to talk about the time he made his debut and how he helped launch the career of Gareth Ellis a week later. Hear more from him on tonight's show.