I'm dedicating my final Ironman, on August 20th in Copenhagen, to my wife and soulmate Jayne and the charity, Brain Tumour Research that's funding work to cure her lifelong and life-changing condition, neurofibromatosis 2 (NF2).

NF2 is a genetic defect (thought not inherited in Jayne's case) that leads to tumours growing on nerves. Jayne lost the use of her left ear aged 18 when a tumour the size of a golf ball was cut away from the acoustic nerve and has since had surgery four times to remove tumours from her brain, ear and ankle. She currently has more than a dozen brain and spine tumours being monitored, including one growing on the nerve to her 'good' ear that has already robbed her of her balance and is destroying her remaining hearing. Jayne's last hope to stop her becoming completely deaf is gamma knife surgery and a cochlear implant.

NF2 affects one in 33,000 people and the diagnosis is especially hard on the young, who suddenly face an uncertain future: not knowing if and when they will lose their hearing, their balance and even their life; a never-ending cycle of MRI scans and waiting for results; never sure whether a headache is just that, or a tumour kicking off. It's a disease that takes a heavy mental as well as physical toll.

A cure for NF2 will be too late for Jayne but the Centre of Excellence of the University of Plymouth's work, funded by Brain Tumour Research, offers hope for future NF2 patients. Please help us with a donation or by sharing Jayne's story more widely to increase awareness and support.

When training for my first full distance Tri a colleague (PJH for those who know) told me that you have to do three to be a 'proper' Ironman. Next month, in my 60th year, I intend to make good on that. The knowledge that I'll be doing something to help Jayne's cause, and that I'll never have to swim again, will sustain me through the next few weeks of hard yards and the race on August 20th.

As ever, I'm covering all entry and travel costs myself. Any donations will go straight to Brain Tumour Research. Please give generously.

Thank you for reading this far.

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