Underwear company Jockey has launched a pair of pants it says will put an end to the appearance of the dreaded 'builder's bum'.

Jockey said the new 3D Innovations line stays in place no matter what position the wearer gets into, preventing the potentially embarrassing occurrence of pants slipping down.

The company spent three years developing the underwear, scanning and measuring 6000 male bodies to understand what happens to male butt cheeks when they move.

3D Innovations are cut on the bias, and feature 1930s couture pattern technology that gives two-way stretch. The pants' cotton/spandex is cut across the grain to give four-way stretch. The two halves are twisted and joined with a seam to give the garments eight-way stretch.

Jockey claims the pants mimic the way the skin itself stretches, giving them the 'stay put' factor and providing a 'second skin' fit.

Marketing manager Ruth Stevens said: "Years of research have gone into the world's only 'stay put' pants. Every little detail of the underwear has been designed to fit the body perfectly, making them comfortable and stylish."

Chief creative officer Victor Herbert said: "For years women have understood the importance of fit and comfort in their underwear but men's pants have remained a 'one size fits all' market to some degree."