For Will Ahmed, the path to building a $10.1 billion fitness startup began with what he calls “the ultimate betrayal.” Who is the culprit? his own body.
Founded in 2012, the Boston-based fitness wearables company currently has more than 2.7 million users worldwide. These customers use Whoop’s screenless wrist devices to track a wide range of biometric data around the clock, from sleep quality to the body’s performance during exercise and recovery. The company achieved an 11-digit valuation in March with a $575 million funding round from a group of investors that included athletes such as LeBron James, Cristiano Ronaldo and Rory McIlroy.
“I have loved sports and exercise all my life,” says Ahmed, 36, founder and CEO of Whoop. He played several sports while growing up and eventually served as captain of Harvard University’s prestigious squash team. He also had an obsession with fitness to the point of chronic fatigue due to “overtraining.” “I was going through periods where I was getting fitter and healthier and then all of a sudden I felt completely weak…and I didn’t know why.”
While studying government and economics at Harvard University, Ahmed pored over hundreds of medical research papers to gain insight, he says. He found that fatigue from overtraining can affect anyone who exercises frequently, not just high-level athletes. He became convinced, he says, that the market was underserved for active, health-conscious consumers who wanted to better understand “what’s going on physiologically inside this person’s body.”
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Before graduating in 2012, he published an original research paper on the topic “Feedback Tools: Measuring Strength, Recovery, and Sleep” and began working on the development of Whoop. Working at Harvard’s Institute for Innovation with co-founders and fellow students John Capodilupo and Aurélien Nicolae, Ahmed wrote an initial business plan and developed an early prototype with physiological sensors.
The years that followed were not always smooth sailing. Investors repeatedly expressed skepticism about the business, and Hoop nearly went bankrupt about six years later, Ahmed said.
“I had never started a company, never had a full-time job,” says Ahmed. “I was building a business at the intersection of hardware and software, data science and medicine,[but]I wasn’t a hardware engineer or a computer scientist or a data scientist or a doctor. So I think there was a lot of skepticism.”
Launching a “very challenging” startup
Mr. Ahmed provided Hoop’s initial funding through an undisclosed sum from friends and family, he said. He spent much of 2012 unsuccessfully trying to convince big investors, estimating that he received a total of 143 rejections in the early years of the company.
In January 2012, Nike had just released FuelBand, a wearable device that tracks activity and calories. The long-rumored Apple Watch was released two years later. “It’s never a good thing when Nike and Apple, two of the best and biggest companies in the world, are competitors,” Ahmed said.
Investors suggested switching to building software for other companies’ wearables, but Ahmed said he believed the surest path to long-term success was to build “an entire end-to-end system,” including both the hardware and the software that powers it.
“It was a really tough time…Every day I was trying to pick myself up and put one foot in front of the other and continue to grow,” Ahmed says.
For him, Whoop’s differentiating feature will ultimately be its wide range of biometric data, including ECG monitoring of blood pressure and heart electrical activity. At the time, these data were primarily available through large invasive devices in medical centers. To collect that data, we needed to build a wearable that could successfully collect the data. Ultimately, this proposal helped Ahmed secure $3 million in seed funding in July 2013 from a group of venture capital investors led by Collaborative Fund.
With the funding in hand, Hoop could finally begin to turn Ahmed’s ambitious obsession into a tangible product. Whoop’s co-founders led the computer science and mechanical engineering elements, with Nicolae becoming chief hardware engineer.
The company started by developing individual technology components, such as LED sensors that non-invasively measure heart activity and blood flow using light, and then worked to combine them into wristbands. The first products appeared on the market in September 2015.
From the verge of bankruptcy to a “real business”
Whoop initially reached out to a demographic of top athletes, hoping that high-profile endorsements would bring instant cash to the brand. Ahmed said in a July 2025 episode of the podcast “How I Built This” that he connected with them through his personal trainer and performance coach. By September 2015, Whoop users included NBA superstar LeBron James and swimming legend Michael Phelps.
But famous customers don’t necessarily translate into reliable sales, says Ahmed. In 2017, Whoop was still not profitable, and at one point that year the company was “a week away from declaring bankruptcy,” he said, adding, “The technology was very powerful, but we still hadn’t figured out how to actually turn it into a business.”
While professional athletes might pay $500 for a fitness band, the broader demographic isn’t, and Whoop needed more sales revenue to cover its research and development costs, Ahmed said. In 2018, Whoop changed its business model to annual membership packages starting at $199 per year. Members will receive a fitness band and access to Whoop’s app, which includes a full suite of health and fitness tracking tools, as well as free software and hardware updates upon release.
Whoop’s subscriber base grew steadily at first, then even more rapidly during the COVID-19 pandemic as consumers’ interest in tracking their personal health increased, the company told CNBC in October 2020. The number of new members doubled compared to the previous year, and the company announced on March 31 that it finished 2025 with positive cash flow.
Whoop founder and CEO Will Ahmed speaks with NFL quarterback Patrick Mahomes.
Source: Oops
However, the fitness wearables market is no less competitive than it was in 2012, still dominated by products like the Apple Watch, which sold an estimated 281 million devices in its first 10 years, Wired reported in April 2025. There are also rival health-tracking startups like Fitbit, which Google acquired for $2.1 billion in 2019, and Oura, which was most recently valued at $11 billion in October.
Ahmed said he plans to further expand Hoop’s subscriber base by adding more international customers (members currently live in 200 countries) and investing further in technology developments, including artificial intelligence. Starting Whoop right out of college was “one of the scariest decisions of my life, because I had no idea what I was signing up for,” he says.
Other entrepreneurs should follow suit and believe in their courage, he added. “It was a huge leap of faith,” says Ahmed. “The lesson I learned is that sometimes you need to take a big leap…if that’s what your inner voice is telling you is right for you. At least for me, the inner voice I had when I was 22 was screaming, ‘You have to start this company.'”
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