Lewis joins the venture, which was launched in May, after working across the magazine industry, having held senior positions at Emap, IPC and, most recently, Hachette.
NatMag-Rodale currently publishes Men's Health and Runner's World in the UK and was the second joint venture NatMags established last year. It also launched ACP-NatMag with Australian Consolidated Press, which will publish new women's weekly Reveal.
Lewis will report into the NatMag-Rodale board and be responsible for managing all parts of the NatMag-Rodale business including magazines, online, brand extensions and new product development.
Duncan Edwards, NatMags managing director, said: "Rita has a huge amount of experience and an enviable track record in magazine publishing. It is testament to the strength of the Men's Health and Runner's World brands that we have been able to attract someone of Rita's calibre to the business."
Lewis joins NatMag after just a year at Hachette Filipacchi, which she joined in January 2004.
"I am proud to be invited to take up a position which offers me the opportunity to work with such strong award winning brands and to further grow the NatMag-Rodale business. The NatMag-Rodale mission -- to inspire and enable people to improve their lives and the world around them -- is an ethos I am passionate about," Lewis said.
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