Stefan van der Fluit is the founder and CEO of FLOWBIO, the London company behind the S1, a reusable sensor that measures water and electrolyte loss in real time.

Stefan's route into hydration came through sport. Trying to go pro as a triathlete, he learnt that dehydration is not a lack of water but the balance of water to salt, and that the only way to measure it was a lab test costing hundreds of pounds. Six years ago he set out to fix that.

In this episode:

Why hydration was the hardest pillar of performance to quantify, and why PepsiCo, Samsung and Coca-Cola all tried and failed to crack it.

What FLOWBIO's data shows in practice, including the athlete who needed seven electrolyte sachets after a session and took one.

Why going reusable forced the invention of AHI, the hydration intelligence FLOWBIO is now building to run inside the wearables people already own.

Why owning the data layer is what makes a company defensible in an AI world.

And why founders should test investors as hard as investors test them.

Connect with Stefan:

https://www.linkedin.com/in/sapvdf/

https://flowbio.com/

In this episode, I sit down with Will Reed. An exited founder and prominent investor in the health industry.

Will spent the first part of his entrepreneurial career building Sideways6, an employee ideas platform that worked with companies like M&S, British Airways, and Primark. After nearly a decade of growing Will exited the business in 2023

Since then Will has immersed himself into the European health scene investing into and advising some of the most exciting emerging companies in the space as well as launching his own business Healthier which builds and scales consumer health products.

In this conversation we deep dive into investing in Health and cover everything you need to think about when raising money in this space including how to think about capital structure in relation to the life you actually want to live, and what investors looks for when assessing new deals.

Connect with Will here:

https://www.linkedin.com/in/wread
https://www.willread.co

In this episode, I sit down with Nicola Gunby, founder of CLIQ, a social networking and community app focused on getting people off their phones and into real-life communities and events.

Nicola quit university at 21, moved to Southeast Asia and Australia with her partner Jason for three years, and came back to her parents' spare room to start MyRev, a marketplace for freelance beauty professionals that was acquired by Revolution Beauty inside three years.

Three months later Nicola and Jason started CLIQ after realising none of the existing social apps were actually helping anyone meet anyone.

We get into raising as a second-time founder, what to watch for as a woman fundraising in a male-dominated investor world, what it's like to build a tech company with your partner, and the stroke Jason had six months into CLIQ that forced a complete reset on how they work.

Plus where the app is heading as it expands internationally.

Connect with Nicola and check out CLIQ here:

https://www.linkedin.com/in/nicola-gunby/
https://www.instagram.com/findyourcliq/
https://www.instagram.com/nicolargunby/

• 00:00:00 Introduction
• 00:02:42 One-Way Ticket To Asia
• 00:09:30 The MyRev Acquisition
• 00:13:42 Three Months Of No's from Investors
• 00:17:48 Where The Idea For CLIQ Came From
• 00:25:35 Building A Company With Your Partner
• 00:31:38 Raising A Seven Figure Round
• 00:38:38 Investor Red Flags And Women's Safety
• 00:44:24 Hiring, Health And Jason's Stroke
• 00:52:39 Rapid Fire

In this episode, I sit down with Richard Carter, CTO of Proximie, a health technology company
using computer vision and connected software to help surgeons collaborate, improve outcomes
and scale expertise across operating rooms.

Richard started his career in law and investment banking before moving into healthcare, looking
for work with more direct impact. At Proximie he’s spent years thinking about how surgery works
as a system, and where technology can improve access, efficiency and patient outcomes.

We get into why surgery is still surprisingly analogue, how Proximie is building infrastructure for
the operating room, and what AI, robotics and data could change about the future of procedural
care.

Connect with Richard and check out Proximie here:

https://www.linkedin.com/in/richiecarter/
https://www.proximie.com/

• 00:00:00 Introduction
• 00:01:40 Why Surgery Is Still Analogue
• 00:07:10 Richard’s Path From Law And Banking To Health Tech
• 00:13:55 The Scale Problem In Surgical Care
• 00:20:42 Building Infrastructure For The Operating Room
• 00:25:49 AI, Robotics And The Future Of Surgery
• 00:33:30 Commercialising In Complex Health Systems
• 00:42:18 Leadership, Scale And Company Building
• 00:52:14 Personal Health, Performance

In this episode, I sit down with Shaun Traynor, founder of kip, a product designed to help people reduce screen time by combining a physical tag with an app to control how they use their phone.

Shaun didn’t come from a technical background and had to figure out how to build both the product and the company from scratch. What started as a personal frustration with phone use
turned into something bigger as he began to understand how deeply behaviour, habit and addiction are tied to the way we use our devices.

We get into why blocking apps doesn’t actually solve the problem, what’s really driving phone addiction, and how kip is trying to coach behaviour rather than just restrict usage.

Connect with Shaun and check out kip here:

https://www.linkedin.com/in/shaun-traynor-183bb717
https://www.instagram.com/kiplife_
https://www.kip.life

• 00:00:00 Introduction
• 00:01:05 The Problem With Phone Usage Today
• 00:03:40 Building kip Without A Technical Background
• 00:08:15 Learning To Build And Solve Problems
• 00:12:30 From Idea To MVP
• 00:17:10 The Behaviour Behind Phone Addiction
• 00:22:00 Why Blocking Apps Isn’t Enough
• 00:24:00 Coaching People To Change Habits
• 00:47:50 Phones, Sleep And Mental

In this episode, I sit down with Dan Strang, Co-Founder of Coopah, a run coach app built for performance-focused runners.

Dan grew up around sport and business, but spent over a decade building and exiting a previous tech company before starting again. Coopah began as a way to fix broken training plans, but quickly became something deeper as the team realised runners needed more than automation to hit their goals.

We get into why most training plans fail, how Coopah combines human coaching with tech, and what happened when Strava announced the acquisition of their biggest competitor, Runna, just days before the London Marathon.

Connect with Dan, and follow Coopah, here:

https://www.linkedin.com/in/dan-strang/
https://www.instagram.com/coopahruncoach/

00:00:00 Introduction
00:00:24 What Coopah Is And Who It’s For
00:01:30 Why Training Plans Don’t Work
00:04:51 Dan’s Background In Sport And Business
00:11:02 Building And Exiting A Tech Company
00:13:56 Starting Coopah And Finding Product Market Fit
00:17:47 The Story Behind Coopah’s Founding Mission
00:19:52 London Marathon Partnership And Early Growth
00:25:24 Strava Acquires Runna And What Happened Next
00:33:03 Repositioning Coopah And Narrowing The Focus
00:48:42 Rapid Fire

In this episode, I sit down with Ryan Hopkins, two-time TED Talker, bestselling author, and Chief Impact Officer at JAAQ

Ryan broke his leg at 19, lost his identity overnight, and spent years battling bulimia, anxiety, and an undiagnosed autism and ADHD diagnosis. Now everything he does is built around one mission: helping people not end up where he did.

We get into why most company mental health programmes don't move the needle, what he built at Jack, and what he's launching next with Healthy, the world's first corporate health operating system.

Connect with Ryan here:

https://www.instagram.com/theryanhopkins1/
https://www.linkedin.com/in/theryanhopkins/

• 00:00:00 Introduction
• 00:01:16 The Mission Behind the Work
• 00:03:30 Finding Identity Through Experience
• 00:06:57 Deloitte
• 00:14:33 Why Wellbeing Initiatives Fail in Organizations
• 00:21:37 JAAQ's Impact
• 00:25:49 Launching The First Corporate Health Operating System
• 00:34:57 Building a Sustainable Culture
• 00:38:29 Rapid Fire

Two ex-Bank of England analysts. One idea that wouldn't go away. The SPORTL story.

Matt and Ryan didn't set out to disrupt fitness. They started with a grassroots sports idea, got told the money wasn't there, pivoted, and landed on something they couldn't shake: why is pay-as-you-go the norm in every industry except fitness?

In this episode we get into the full story. The validation walks around London at 6pm after full-time jobs, the fundraising wins that weren't wins until the money hit the bank, building a team of five before the product launched, and why the fitness industry is one of the most surprisingly collaborative spaces either of them have encountered.

What we cover:

• Why they walked away from stable Bank of England careers
• How they validated with 250 gyms before writing a line of code
• Raising smart money over fast money and turning down property developers
• Building culture early: run clubs, autonomous teams, and no two days the same
• The biggest bet they've taken so far
• Where SPORTL needs to be in 12 months
  
  

Best line of the episode: "I've never been busier. I've never worked harder. I've never been poorer. I've never loved work more."

Health Stack is the podcast for founders, operators, and investors building technology companies in health and human performance.

New episodes every two weeks.

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