The agency pitched against Spinnaker, Maher Bird Associates and Hicklin Slade & Partners for the brief, which includes print, outdoor, in-store and direct marketing campaigns for the health and fitness chain.
Kitcatt Nohr Alexander Shaw, the incumbent on the account, was not involved in the pitch.
The agency had worked on campaigns for the gyms since 2006, when it was appointed without a pitch.
The win is Mustoes' second since it merged with the integrated agency, Geronimo Communications, last month.
Last week, the agency secured the advertising account for the Milk Marketing Forum following a pitch against M&C Saatchi, Delaney Lund Knox Warren & Partners and the Scottish agency Merle.
The review was handled by the AAR.
.jpg)
.jpg)