He deadlifted 145kg, bench pressed 90kg and squatted 122.5kg for a combined total of 357.5kg, around the same weight as your average rugby front row.
Cooke said he enjoyed the experience down in the capital.
"I love powerlifting and it was good to catch up with my friends from Otago," he said.
"I had a really great time. I had to do some fundraising to get there too."
Cooke sold eggs, kumara, pumpkins and asparagus to fundraise his trip down to Wellington and it paid off.
Not content with just competing in Special Olympics events, Cooke has made a splash on the national scene.
Competing in October's New Zealand Benchpress Championships, hosted by Whangarei, Cooke won the U74kg junior division with a lift slightly better than his 90kg in Wellington, hoisting 92.5kg.
That was the last year Cooke could compete in the junior division so he knows it'll be a big challenge to repeat the feat in 2018. However his competitive nature and passion for the sport should hold him in good stead.
When he and his mother, Sharon, returned from Wellington with a heavy stack of medals, Sharon jokingly asked Josh if he wanted to give the code away next year.
It's fair to say he wasn't impressed in the slightest.
"Don't bring that up," he said.
Cooke now will enjoy some well-deserved time off because the lifting season has concluded for the year.
He will now look to help out his mum in their home garden and go down to Hikurangi's fire station to do cadets.