My mate Dan is one of my best friends, and one of the reasons why I get to do the best job in the world. He's been there, supporting my work as a science communicator from the very beginning, and he's been instrumental in forming a community around my videos. He also has cystic fibrosis. Without the work of the CF trust, I don't know if he would be here today, or if I would have even met him.

This is my attempt to give something back, and to help people like Dan live their best, fullest lives.

I'll be running the Bath Two Tunnels half marathon on the 15th of August. I'm not a natural runner, and while I have been training for several weeks, I'm not feeling very confident that I'll be able to finish the course, let alone in good time. Any and all donations will make the sweat and pain and ache of training absolutely worth it :)

Cystic fibrosis (CF) is a life-limiting genetic condition affecting more than 10,000 people across the UK. It affects the lungs and digestive system and can cause chronic infections and reduced lung function. Currently, half of those with CF will not live past age 41.The Cystic Fibrosis Trust is fighting for a brighter future for people with CF and their families by funding cutting-edge research, driving up standards of care and supporting people with the condition and their loved ones every step of the way.