Zef Eisenberg founded Maximuscle in 1995 with £3,000 and turned it into the UK's No.1 sports nutrition brand in just six years. Today it is now Europe's largest brand of its kind with distribution across the multiples, gyms, healthfood shops and online sales.

Its organic growth was achieved with no funding of any kind. During this time he was responsible for the introduction of many nutritional firsts to the sports industry, including products such as; Whey Protein, HMB and Creatine; products now used by England cricket, rugby and Premier League football clubs. He pioneered the world's first independent ISO17025 certified test for sports nutrition products, allowing Maximuscle products to be the first of their kind to offer 100% safety for elite athletes.

In June 2004, he sold a share of the business to private equity house, Piper Private Equity. In December it was sold for £75m to Darwin Private Equity in a refinancing deal, with Zef remaining as president of the business. He is also a prolific author on the benefits of a fitness lifestyle and strongly believes that 'fit is the new rich'. A passionate campaigner for sensible EC legislation on food, he writes for several national magazines and is the Vice-chair of the European Specialist Sports Nutrition Alliance (ESSNA). He was the winner of Ernst and Young's National Entrepreneur of the Year Award in 2002.