She started working with a personal trainer and hasn't looked back, clocking up countless races and dropping 60kg in just 18 months.
Cleave has been invited to race in the New York Paratriathlon on July 1 where she will represent New Zealand as an Achilles International Athlete, a charity which encourages the disabled to take part in sporting events.
She said one of the biggest challenges was needing a guide for training sessions and competitions, which often doubled her costs.
"Being visually impaired and running there's difficulties with footing so the guide needs to be able to tell you if the terrain is bumpy or has tree roots so you can adjust your pace."
Cleave said she wanted to coin the phrase "be inspired by you" and encourage everyone to tackle their own challenges.
"People have all sorts of things they overcome and if you take the time to look at your life, through your experiences, and see what you've overcome in your journey then you'll find inspiration for yourself in your own story."
She said she didn't compare herself with others, instead focusing on the progress she had made since she started eating well and training hard.
"The main thing that changed the path I was on is this mind shift that if you think of everything you do in your life as a choice; how you behave, react, act.
"Everything is a choice and if at each decision point, however small it is, you make the best choice you can you'll be living the best life that you can and you never know where that might take you."
She has set some hefty goals, aiming to rank in the top 10 paratriathletes in the world (currently ranked 14th) and be the first vision-impaired New Zealander to race at the ITU World Paratriathlon Championships finals this year alone.
However Cleave, who works as an office manager at the Blind Foundation, said she needed to raise about $20,000 to cover travel costs for her and her guides for overseas races in the lead-up to the events.
She was setting up a Givealittle page, which was yesterday pending donor validation.
In the meantime she said her personal trainer had set her a 10km time goal of 65 minutes for this weekend's competition, having run the same leg in last year's marathon in one hour and 14 minutes.
Those wishing to donate to Cleave can visit www.givealittle.co.nz/cause/shannon-cleave-para-triathlete#.