Orangetheory Fitness has over 1,100 studios across the globe and is expanding at an impressive rate — there are currently 500 more branches in the development pipeline.

The company recently reached $1 billion in systemwide sales for 2018 and claim to be one of the fastest-growing fitness franchise brands on the planet.

Orangetheory offers heartrate-based workouts, combining technology and science with community and accessibility for all.

We tried it out and spoke to the founder and long-time fans to find out the secret of the brand's success.

"Rachel, hi! So good to see you again," says the smiling woman behind the counter as I walk into Orangetheory Fitness in Islington, north London.

It's my second visit to the fitness studio. Not just that week, but ever.

But unlike a lot of customer-facing roles, the friendliness seems genuine, like they really are glad to see me again.

Every person who walks through the door is greeted in a similarly warm way, and this personal touch is one of the factors that keep people coming back for more.

At a time when keeping fit has never been cooler and fitness-lovers are spoilt for choice when it comes to places to workout, successfully maintaining a loyal customer-base is not to be sniffed at.

Welcome to Orangetheory, the heartrate-monitoring fitness studio which has taken the world by storm — in fact, it reached $1 billion in systemwide sales for 2018 and, as a result, claims to be one of the fastest-growing fitness franchise brands on the planet.

Orangetheory currently has more than 800,000 members with over 1,100 studios in 49 US states and 22 other countries, and there are another 500 studios in the development pipeline.

Prices vary depending on location, but a monthly "Premier" membership (meaning unlimited classes) costs around £109-£149 in the UK, or around $129-$290 in the US, so it's easy to see why the business has been successful.

A portion of every Orangetheory workout is spent on the treadmill, but you can go at your own pace. Orangetheory

"We are a science-backed workout that produces results," Ellen Latham, its creator and cofounder, told Business Insider.

"That is why people come to a fitness product … for guaranteed results. Our technology allows our members in real time to see how their body is responding. What you do not measure you cannot achieve."

How it works

Orangetheory, which opened its first studio in 2010, distinguishes itself from other fitness franchises with its focus on heartrate.

Before entering the fitness studio, you strap a heartrate monitor around your arm which is linked to your personal profile.

There are three big screens in the studio displaying each person's stats: heartrate, calories burned (you input your weight amongst other details upon signing up), and "splat points" ie. how many minutes your heartrate has been in the red or orange zones.

Rowing machines are also a part of every workout. Orangetheory

Heartrate zones are divided into grey (rest), blue, green, orange, and red, and it's the orange zone you're aiming for, hence the name (and the matching interiors — yes, it feels a bit like EasyJet).

In an Orangetheory workout, each person is meant to try and achieve 12-20 minutes with their heartrate in the orange zone (over 84%).

The reason for this is all about "EPOC": Excess Post-exercise Oxygen Consumption. Essentially, the afterburn.

As your body recovers post workout, your metabolism stays raised, and you continue to burn more calories afterwards if you've hit that all-important orange zone.

It's not too hard to do, either — I managed more than 20 splat points each of the five times I visited Orangetheory.

A "multi-vitamin of metabolic training"

Orangetheory workouts are 60-minute group training HIIT sessions, with time split between treadmills (raising the heartrate), rowing machines (non-impact full-body work), and floor work with weights (muscle-building).

The founders call the workouts a "multi-vitamin of metabolic training," and they've been designed with fat-burning in mind.

Everyone around the world will do the same Orangetheory workout on any given day, but they won't know what it will be until they walk through the door — each workout falls into one of three categories: Endurance, Power, or Strength (or ESP, which is a combination of all three).

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The focus is slightly different depending on the category, but customers are kept in the dark until they arrive so they don't deliberately avoid their least favourite type of training.

"Most people want to do workouts they like, never realising it is usually the ones they don't like that will give them the biggest change," Latham says.

Of course, this could also mean that someone accidentally always does one type of workout, but there isn't actually too much variation between them all.

Twenty-eight-year-old journalist India Dowley, who is based in London and has been going to Orangetheory for three years, told Business Insider the way coaches get to knock their members and encourage them to reach the orange zone is part of the appeal.

"This kind of dual set-up combining forward-thinking tech with a personal, human touch means OTF successfully caters to all levels of fitness, without anyone feeling either left behind or unchallenged," she said.

Every workout also ends with a stretch and mobility session too, which isn't the case with all fast-paced HIIT classes.

It taps into our obsession with tracking

Orangetheory has tapped into our current obsession with tracking — from our sleep to what we eat, we can't get enough of self-monitoring. Not only are you able to assess your stats during an Orangetheory workout, but a detailed report will be emailed to you afterward.

It's not about competing with others, though, and the sense of community considering the scale of the organisation is impressive.

In fact, Latham believes Orangetheory's accessibility has been the key to the company's growth: "Any person no matter what their fitness ability level is can succeed."

The studios are, unsurprisingly, very orange. Orangetheory

Unlike many fitness studios, Orangetheory isn't intimidating and all levels are catered for — for example, treadmill levels are divided into "walker," "jogger," and "runner," and if you can't run at all, you have the option of going on a cross-trainer or exercise bike instead.

The trainers push you, but they're encouraging too, regularly using people's names during workouts. Everyone leaves the studio with a high five.

Technology and community aside, for some the appeal of Orangetheory is simply that they know they're going to get a full-body workout in and not have to think.

"Despite classes of up to 30, it's a very personalised workout thanks to heartrate monitors that allow you to track your progress throughout, meaning you know when you're not training where you need to be — which will be different from the person next to you," Dowley said.

"It works for me because I know that as long as I put on my gym kit and turn up the rest is sort of done for me."

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