The 27-year-old, who with Mark Hunter won gold in Beijing 2008 in the lightweight double sculls and an emotional silver in London 2012, has not ruled out a future "sporting challenge".

The 2006, 2010 and 2011 world champion said: "I have been part of the GB rowing team for nearly a decade and during that time have shared a tremendously successful period with some of the world's finest athletes.

"Winning the gold medal with Mark at the Beijing Games in 2008 is as memorable today as it was those six years ago.

"To then have the chance to compete on home water in London and to win silver in front of a rapturous home crowd was an honour and something I will never forget."

Purhcase and Hunter were pipped by Danes Mads Rasmussen and Rasmus Quist Hansen in the London final, with the British pair looking distraught at missing out on gold.

Minutes earlier, there was drama when Purhcase's seat broke within moments of the race getting underway.

The race was restarted at the seat broke within the first 100 metres of the race.

Gold in the Beijing 2008 Olympics was a career highlight for Zac Purchase (right), who powered to lightweight double sculls victory with Mark Hunter ©Getty Images



"Since London, I have spent time reflecting on those results and I felt it was the right time to step away from rowing to explore other opportunities," said Purchase.

"I plan to keep fit just in case a sporting challenge presents itself.

"Rowing has played a significant part in my life, and was how I met my wife.

"I am indebted to everyone who has supported my career as a lightweight athlete over the years, particularly Fliss, my wife and my parents.

"I wish the British team well in their build up to the Rio Olympics and beyond."

Purchase won the World Rowing Under-23 Championships in 2005 in the lightweight single sculls, before winning the same event in the World Rowing Championships the following year.

He formed a partnership with Hunter in 2007 in the lightweight double sculls, going on to win Olympic gold and silver, and double World Championship gold.