Fireman was born to a Jewish family and raised in Brockton, Massachusetts where he attended Boston University, but did not graduate. After working in a variety of jobs, including for a family-owned sporting goods store, Fireman acquired the North American sales rights to Reebok in 1979. He later bought the British-based parent company in 1984. Capitalizing on the increasing popularity of aerobics, particularly with women, Fireman grew the company and issued an IPO in 1985. By visiting gyms and high schools across the country, Fireman conducted first-hand market research. After the IPO, Fireman alternated between building a real estate empire and serving as the CEO of Reebok. Fireman sold Reebok to Adidas in 2006 for $3.8 billion; Fireman himself made $800 million from the deal. In 2009, Fireman founded Fireman Capital Partners, an investment firm. Fireman Capital has bought major stakes in Newton Running, Hudson Jeans, and Evolution Fresh.