New research suggests that male athletes should skip breakfast before training.
In fact, the study from Massey University claims that missing the first meal of the day benefits male athletes.
Steve Stannard, head of the University's School of Sport and Exercise, insists men and women burn fat differently.
"We've had the wool pulled over our eyes by breakfast cereal companies for so long now," Stuff.co.nz quoted him as saying.
He added: "There's this whole industry, built up around sports bars and drinks, based on the idea that if you have carbohydrates before exercise, you can go for longer and harder. A lot of it's rubbish."
Stannard conducted tests on two groups of cyclists for a period of four weeks,to reach the conclusion.
One group consumed a high carbohydrate breakfast before training, while the other had it after exercising.
Stannard said, cyclists who ate after exercising stored higher levels of muscle glycogen, which prolonged muscle energy, and increased power.
Also, it was noted that the female cyclists improved their ability to burn fat when they trained after breakfast.
He said: "Our results suggest that, for men, training before breakfast encourages the muscles to adapt in a more accelerated fashion than if training was always done after eating a high carbohydrate meal.
"Depending on your level of fitness, that might range from two hours' cycling to walking down the street and getting the newspaper.
"It could be to do with sex hormones and possibly the way fat is stored in the body."
The research has been published in the Journal of Science and Medicine in Sport.