Parkinson was educated at Auckland'sSaint Kentigern’s College, before relocating to Nelson to join the Crusaders Academy and play for club team Stoke. He had an early taste of Super Rugby when he played four minutes for the Crusaders' top side in a practice match against the Highlanders in Oamaru in 2016, at 19 years of age. Parkison joined the Tasman Makos wider training group in 2016, having previously represented the New Zealand Barbarians Schools side. He made two appearances for Tasman in the 2016 Mitre 10 Cup and was recalled into the squad for 2017. Parkinson’s hard-working attitude earned him an Investec Super Rugby contract with the Highlanders for the 2018 season, debuting against the Crusaders towards the end of the season. In 2020, Parkinson established himself as first-choice lock for the Highlanders, during the Super Rugby Aotearoa competition, drawing praise for his performances and work-rate.
In 2018, Parkinson was selected for the Maori All Blacks tour of the USA, Chile and Brazil, thus following in the footsteps of his uncle Matua Parkinson, who played for the side and also captained the New Zealand Sevens team. During the tour, he started all three games at 5 in what was a clean sweep, however, he was yellow-carded in the match against the USA for a body slam on Eagles number 9 Shaun Davies. Parkinson represents his iwiTe Whānau-ā-Apanui, from the eastern Bay of Plenty and East Coast regions of New Zealand'sNorth Island. About his involvement in the Maori All Blacks, Parkinson said: "It was the icing on the cake of a pretty awesome Mitre 10 season" He also cited Chile as his favourite destination on the tour, because of the weather, the people and the training facilities, while also saying to be proud to be contributing to growing the sport around the world.
Style of play
From the position of lock, Parkinson stands out in the lineout and for his work around the park, using his big frame to carry the ball into defenders and setting teammates with his offloads. His dimensions made his Highlanders' captain Ash Dixon label him as a "baby giraffe".