You mightn't want to quit those sweaty gym sessions just yet, but shivering in the cold could be the next big thing for your health.
After 15 minutes of cold your body will be pumping out two hormones that could turn unhealthy white fat into energy-burning brown fat.
That's the theory behind Australian scientist Dr Paul Lee's research published in the journal Cell Metabolism.
Dr Lee has just returned from the US where he conducted human trials that show shivering and moderate exercise produce the same energy-burning hormones.
He has also conducted laboratory experiments that show the hormones are able to turn human white fat cells into healthy brown fat cells.
Until a few years ago it was thought brown fat was found only in newborn babies to keep them warm, he says.
But research has shown adults retain brown fat. In babies it is mostly around the upper back and shoulders and in adults it is around the neck.
"The more brown fat an adult has, the leaner they are and the lower their blood sugar is," said Dr Lee, from Sydney's Garvan Institute of Medical Research.
"If we can increase the amount of brown fat in the body, it may protect people from gaining weight and developing diabetes."
Dr Lee's study has shown that shivering for 10 to 15 minutes at 14C to 16C has similar hormone-producing results to an hour of moderate cycling.
There were also benefits at a less chilly 19C, he said, emphasising more research was needed to determine safe and effective levels of exposure.
"Our results showed that moderate exposure to cold may be helpful, but the importance of a healthy diet and regular exercise should not be neglected."
Dr Lee was optimistic his work could add a new dimension to the battle against diabetes and other diseases.
"The current strategies against obesity are not curbing the the rise. Brown fat may not be a solution on its own, but it opens new avenues," he said.
"Brown fat is very healthy. It helps burn up calories and sugar," said endocrinology Professor Don Chisholm of Garvan and St Vincent's Hospital, Sydney.
"The cold is a strong activator of brown fat. It may be that modern humans lost its effect because we no longer get cold.
"A question is whether we can find pharmacological or lifestyle methods to activate brown fat."