Muñoz was born in La Plata, Argentina. He was a self-made man, who rose from humble beginnings to become the owner of various agencies specializing in finances, tourism, and insurance, as well as a building company and a hotel chain. In November 2004, he was elected President of the football club Gimnasia y Esgrima La Plata, the oldest club currently affiliated to the Argentine Football Association (AFA). He occupied this position until the end of 2007, when a new management committee was chosen.