James Hadley-Piggin has completed seven marathons in seven days, raising money for All Matters Neurodiverse.
The 27-year-old English teacher ran 26.2 miles each day for seven consecutive days, taking on courses in England, Wales, Guernsey, Sark and Jersey.
He set himself the challenge to raise awareness of neurodiversity.
James, who has dyspraxia and undiagnosed ADHD, has almost doubled his £2,000 fundraising target, collecting nearly £4,000 in sponsorship through his crowdfunding page.
He crossed the finish line at the Weighbridge on Sunday and told Channel 103 how he felt:
"It's like 'Wow, how did I do that?' and I almost kind of miss it.
"It really shows you how much people are there for you, and it really brought a sense of community spirit, which was so humbling."
James is organising an event next month to encourage more neurodiverse islanders to take up sport.
'Breaking Barriers' at FB Fields on 14 September aims to showcase the transformative power of activity and fitness.
"I work with lots of neurodiverse people, and being neurodivergent myself, as a child, I never had these opportunities.
"Trying to do sports like rugby, hockey, football or cricket, I could never do them because no one had belief in me.
"I think it's really important to empower people like myself and take away any stigma they may feel."
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