SoulCycle has taken the US by storm, with fitness studios spreading throughout California, Illinois, Connecticut, Florida, Maryland, Massachusetts, and New York — and it's pacey takeover of the fitness world doesn't show any signs of cooling down and will undoubtedly spread "across the pond" to our shores.

Popular features of the SoulCycle brand include a convenient membership model, exclusive exercise classes, celebrated instructors, contemporary facilities, and a zen atmosphere — but none of this is new. What sets this fitness creature apart from its numerous competitors is its word-of-mouth marketing strategy: SoulCycle does not market its brand, its customers do.

Consumer interest in SoulCycle is created through social media — 'selfies' are actively encouraged before, during, and after classes and the global social media sphere is swimming with photos of celebrities, CEOs., and even First Lady Michelle Obama reaping the benefits of the SoulCycle lifestyle. And, what's more, these human billboards are frequently sporting the brand logo on their clothing and accessories which the company releases in monthly fashion lines and capsules. With product sales making up an increasing percentage of SoulCycle's revenue, not only is the company benefiting from free advertisement both inside and outside the studio, it's increasing its merchandise sales by using this marketing strategy.

In this digital world, social media marketing is fast becoming the most effective way to advertise your brand as consumer trust in celebrity endorsements, whether paid or otherwise, seems to be on the rise.

But, beware, this new approach to marketing doesn't mean you can ignore legal obligations regarding unsolicited email opt-in requirements.