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As a physical trainer in the Royal New Zealand Navy, athleticism was a huge part of Jack Church's life.
But all that was put on hold when tests revealed his heart had swelled and he would need a heart transplant.
Two years on, and Jack is about to put his new heart to the test when he competes in the Invictus Games in Germany.
He'll run for the New Zealand team in the 100 metre and 200 metre sprint races, but before that he's found some time to tell us about his journey.
Invictus Games Photo: www.invictusgamesfoundation.org