Pimenta has competed since the late 2000s. His first major result came at the 2010 World Championships in Poznań, Poland, when he won the K-2 500 metres silver medal together with João Ribeiro. One year later, he contributed to the Portuguese K-4 1000 metres gold medal at the European Championships in Belgrade, Serbia, and claimed a bronze in the K-1 1000 metres. Together with Emanuel Silva, he won the silver medal in the K-2 1000 metres event at the 2012 Summer Olympics in London, which was Portugal's only medal at these Games.