Mangabeira graduated from the University of Florida with a bachelor's degree in food and resource economics in 2004.

[2] At the 2004 Summer Olympics, Mangabeira made it to the finals of the 100-metre butterfly where he finished in sixth place, beating the South American record, and swimming alongside well-known swimmers like Ian Crocker and Michael Phelps.

[11] Mangabeira also qualified to compete in the 2007 World Aquatics Championships in the 100-metre butterfly and 50-metre backstroke, but did not make it past the initial heats.

[1] In 2009, Mangabeira competed in the 2009 World Aquatics Championships in the 100-metre butterfly and 4×100-metre medley relay, and reached the finals in both events, finishing eighth in the individual race and fourth in the relay, which he swam with Guilherme Guido (backstroke), Henrique Barbosa (breaststroke) and César Cielo Filho (freestyle).

At the 2010 South American Games in Medellín, Mangabeira won a gold medal in the 4×100-metre medley.