Cooke has been one of GB's most consistent performers
Britain's Rebecca Cooke is to quit elite swimming at the age of 24.
The current Commonwealth 800m freestyle champion and former world bronze medal winner failed to make the British team for this summer's Olympics in Beijing.
The City of Glasgow swimmer, who now wants to complete her physiology degree, said: "I was disappointed because that was my one remaining goal.
"This has brought forward my retirement by a few months. I had already resolved to make the change after Beijing."
As well as her bronze at the Worlds in Barcelona in 2003, Crawley-born Cooke claimed bronze medals at the 2006 World Short-Course and European Championships.
She also won three golds and two silvers at two Commonwealth Games, competed at both the Athens and Sydney Olympics and has held both the British 800m and 1,500m freestyle records.
British Swimming head women's coach Ben Titley said: "Becky has been a fantastic athlete, role model and personality to have on the British team.
"She's one of our toughest competitors, and testament to this is her success at world, European and Commonwealth level, plus the fact she's competed in two Olympic finals.
"Becky has a reputation for going that extra mile in training and I'm sure that work ethic will serve her well outside of the sport."