Bradley Wiggins has dismissed the marginal gains process at the centre of British Cycling's success under Dave Brailsford as "a load of rubbish" and called Victoria Pendleton "bit of a milkshake".
Along with fellow Olympic gold-medallist Pendleton, Wiggins was critical of sports psychologist Dr Steve Peters, who worked with Brailsford at British Cycling and Team Sky and created the "chimp paradox" model for dealing with pressure.
Former Olympic champion Chris Boardman originally headed up British Cycling's "Secret Squirrel Club", now known as "Room X" under head of technical development Tony Purnell, to find any slight advantage through modifications to bike technology and riders' clothing.
"That may work with some people, but as Roy Keane would say: it's utter nonsense."
Wiggins won eight Olympic medals, including five golds, as well as the Tour de France for Brailsford's Team Sky but, speaking at a corporate event reported on by Eurosport, said: "A lot of people made a lot of money out of it and David Brailsford used it constantly as his calling card, but I always thought it was a load of rubbish.
"It's a bit like the whole chimp thing. At the end of the day, chimp theories and marginal gains and all these buzzwords - a lot of the time, I just think you have got to get the fundamentals right: go ride your bike, put the work in, and you're either good or you're not good.
"Sometimes in life or in sport, whatever, you're either good at something or you're not. That's what makes you a better athlete: your physical ability and whether you've trained enough - not whether you've slept on a certain pillow or mattress."
Pendleton, who won sprint gold at Beijing 2008 and the keirin at London 2012, has credited Dr Peters as a major part of her success.
But Wiggins said: "Vicky's a bit of a milkshake anyway. You can overanalyse things but at the end of the day, it's about your ability and whether you're a better athlete than the other person or not.
"Whether you've come to grips with this other person living inside you, it's all a bit... well, each to his own. That may work with some people, but as Roy Keane would say: it's utter nonsense."
Wiggins made no mention in the interview of the ongoing investigation into a medical package delivered to him at the 2011 Criterium du Dauphine.