After a glittering youth career in which he won global medals at junior, under-23 and Universiade level, Cohen graduated to the senior ranks with a fourth place finish in the double scull alongside Rob Waddell at Beijing 2008.

Alongside new partner Joseph Sullivan he then won World Championship titles at Karapiro in 2010 and Bled 2011 before winning once again at London 2012 to highlight a golden period.

However, although originally planning to continue his partnership with Sullivan up to a title defence at Rio 2016 Cohen has faced heart problems which have disrupted his preparations and forced him to withdraw from this years World Championships in Chungju.
 
When outlining the problems, he described how "once you're into the race, your heart isn't in rhythm, oxygen is running out and you lose power and become weaker and weaker as the race goes on."

Nathan Cohen and partner Joseph Sullivan celebrate after winning the double sculls gold medal at London 2012 ©Sports Illustrated/Getty Images


With the problem failing to improve Cohen has admitted that announcing his retirement was "not a decision he took lightly" he that knew it was "the right time."

"I have thought about it very hard over the past few months and I feel I have achieved everything that I wanted to achieve in the sport," he added.

Cohen was a key member of a generation of top New Zealand rowers, including other London champions in single sculler Mahe Drysdale and dominant pair, and world rowers of the year for 2013, Hamish Bond and Eric Murray.

However while New Zealand's other Olympic titles were won from the front, Cohen and Sullivan gained a reputation for  producing a strong finish and won gold in London with a typical and thrilling late burst over the closing stages.

Cohen is the latest in a growing list of London 2012 rowing champions to announce their retirement - following the likes of Great Britain's coxless four champion Tom James and South Africa's lightweight four winner Matthew Brittain.