Isaac began his rowing career at Edgewater College in 2007 rowing out of St George’s Rowing Club.
He has won three red coats in the National championships. In 2017 he won a red coat in the men’s premier coxless quadruple sculls; 2019 in mens Premiere coxed eight and 2021 in the men’s premier coxless quadruple sculls.
In 2013 and 2014 Isaac was an U23 World Champion in the men’s eight.
He went on to represent New Zealand in the eight. He came fourth at the 2015 World Rowing Championships with the men’s eight, qualifying the boat for the 2016 Olympics. He came sixth with his team at the eight competition in Rio de Janeiro.