Fitness apparel startup Gymshark was started by a 19-year-old and is now one of the fastest growing companies in the world - here's what the clothes are actually like

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• Fitness apparel startup Gymshark was founded by a 19-year-old in his mom's garage in 2012.
• The company is reportedly generating $128 million in annual sales as of 2018, making it one of the fastest-growing in the world.
• Much of its success is due to a big social media presence, including exposure via celebrity trainers.
• The marketing is effective, but most importantly, the gear itself is great: affordable, breathable, and very flattering.
• Find Gymshark's bestsellers below. Find other fitness startups making great leggings here.

Ben Francis was 19 years old and driving a car that smelled permanently like pizza. He was working as a delivery person at the time, just as he decided to found a fitness apparel company called Gymshark out of his mom's garage.

That was 2012. In 2018, Gymshark has reportedly generated $128 million in annual sales, and become one of the fastest growing companies in the world.

The UK startup has a few key tools to thank for its explosive success: an early trade show that sent daily sales from $400 to $42,000 in a single day, and a masterful use of social media.

Gymshark's main Instagram - which, as of November 2018, has 2.5 million followers - is flush with Gymshark-clad celebrity trainers (including Kim Kardashian's trainer Melissa Alcantara), big-time athletes, and fitness icons with millions of social media followers on their own. The company's Facebook page has 1.5 million likes. Facebook COO Sheryl Sandberg reportedly even used the company as a model example of European brands excelling at growing a business on the platform.

But Gymshark isn't just successful because it has figured out social media. It is successful because it is one of few companies to accurately understand "gym culture" - and to then make spot-on products for gym-goers.

Young gym-goers want to look and feel good going to the gym. They want functional gym clothes - sweat-wicking, flexible, and durable - that perform well, and, yes, look really good on them. Gymshark understood that, and it delivered.

Here's an example. Probably the most iconic Gymshark item is their $38 Flex Leggings (seen above). They're breathable, flexible, and no-nonsense - the high waistband is compressive, slimming, and supportive, and the seamless construction moves with you without complaint. But they're also designed with a none-too-subtle hand to be extremely flattering and "bum-contouring." The color contouring is overt in light colors, and modest enough to go almost unnoticed in the darker colorways.

The clothes are also unusually affordable. For staples like leggings, shoppers can pay as little as $35. At other brands with comparably cult-like followings, the same shoppers might pay closer to $100. Best-selling shirts go for as little as $25. Fabric compositions may not be the most elegant in the game, but they'll suffice for the average gym-goer - especially for the frequent athlete who can't spend $50 on shirts they need in bulk. Plus, they look really good.

Gymshark does all the trends you want in a uniquely masterful way and at an affordable price. The men's $45 Taped Joggers have tapered legs but an overall slouchy fit so your shape is discernible. The women's $46 Solace Bottoms are similarly well-executed: fitted through the leg, concealed zip pockets, high-rise enough to reach the part of your waist that's universally flattering, and - best of all - there's a seam on the back that prevents the cute high-rise from looking like a pair of your grandmother's pants in the back.

All in all, it's not the brand that's going to get you many "cool" points in alternative Brooklyn coffee shops. But you're probably not wearing it there. It's a little "bro-y," so steer clear if that's going to bother you. But, ultimately, it doesn't really matter - it's pretty great stuff for a price that most gym-goers are happy to pay in exchange for the functionality, and, more honestly, probably for the style.

Below are a few of Gymshark's bestsellers: