#335 Unlocking VO2 Max: TIME-Saving Secrets (Why Zone 2 Alone Won’t Cut It) | REHIT And Metabolic Health With Ulrich Dempfle
Today, I’m joined by Ulrich Dempfle, the innovative mind behind the CAROL Bike. Ulrich’s journey is fascinating—he started as a mechanical engineer in Europe, became a pioneer in hospital AI systems, and is now laser-focused on bringing cutting-edge fitness tech to regular people, like you and me.
If you’ve been overwhelmed by all the talk about Zone 2 training—endless hours of slow, steady-state cardio being hailed as the “ultimate” longevity workout—this conversation is for you. We get into the realities of what Zone 2 actually does (and doesn’t do), why most people don’t realistically have time for four to eight hours of cycling or jogging every week, and, more importantly, what you can do instead that’s actually proven to boost your health.
Ulrich shares the science (and his personal story) behind alternate, time-efficient workouts—like just two 20-second, all-out sprints—that significantly improve your VO2 max and metabolic health. Spoiler: It’s possible to get results that move the needle for longevity in just a few minutes a week.
In this episode, you’ll hear us break down what VO2 max means, why it’s hands-down the most important fitness marker for lifespan, and how even a busy parent or a non-athlete can build and maintain real, measurable improvements. We also talk about the misconceptions around cardio, exercise efficiency, and how to leverage the latest tech for your own fitness goals—without needing to spend hours every day or sacrifice your other priorities.
So whether you’re an athlete, a weekend warrior, or still looking to get off the couch, this episode is packed with practical advice, honest conversation, and plenty of motivation. Dive in and discover how to take control of your health and longevity—without wasting a minute.
The folks at CAROL Bike are offering a pretty cool deal if you want to give it a try. 100 day FREE trial! Visit http://carolbike.pxf.io/Nat or use code NAT100 for a free 100-day trial.
Learn more from Ulrich Dempfle below:
What We discuss:
Zone 2 training: hype, benefits, and limitations ... 00:08:00
VO2 max: definition and importance for longevity ... 00:10:00
The impracticality and issues with Zone 2 for most people ... 00:15:00
Downsides of long-duration steady-state cardio ... 00:18:00
Why strength and mobility also matter ... 00:17:00
Carol Bike and REHIT: efficient fitness for longevity ... 00:31:00
REHIT’s proven VO2 max and metabolic improvements ... 00:36:00
Personalization and ease-of-use with Carol Bike ... 00:49:00
Carol Bike’s versatility: multiple workouts and app integrations ... 00:57:00
Who Carol Bike is for and safety notes ... 01:10:00
Carol Bike trial info, research, and closing ... 01:12:00
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