He competed at the 1980 Summer Olympics in road racing and finished in 26th place.

Among his 14 victories were two stages at Alpe d'Huez in the Tour de France and a national championship.

On the Dutch TV-show Reporter, Steven Rooks, Maarten Ducrot and Winnen admitted taking doping in their careers.

"I was very bad and had the choice: go back to home or to provide me with testosterone."

During his career with Raleigh, Panasonic and Buckler, Winnen used testosterone, amphetamines and corticosteroids.