5 Minute Cardio? The Science of Reduced Exertion Interval Training with Ulrich Dempfle


Meet Ulrich Dempfle, the CEO and co-founder of the Carol Bike, a game-changing exercise equipment that offers efficient workouts in just a few minutes. In this episode, we discuss the psychological resistance to shorter workouts and how the Carol Bike overcomes this by delivering effective results in a short time. The workouts involve intense 20-second sprints, proven to be manageable and beneficial. We explore the science behind the Carol Bike’s short-duration workouts and its impact on fitness indicators.

The Carol bike is not just any exercise bike that can be replaced with running or ordinary bikes. Its specialized design and technology make REHIT more accessible, effective, and personalized, providing a superior exercise experience and accommodating a wide range of abilities and ages.

“VO2 max is probably the most important physiological marker and predictor of future health.”

Dr. Stephanie


The Science Page on Carol Bike’s website

Effect of Number of Sprints in an SIT Session on Change in V˙O2max: A Meta-analysis

Reduced Exertion High-Intensity Interval Training is More Effective at Improving Cardiorespiratory Fitness and Cardiometabolic Health than Traditional Moderate-Intensity Continuous Training

www.carolbike.com use code: BETTER for $100 off


0:00:01 The Clear Benefits of Exercise
0:00:52 Cardio Respiratory Fitness and VO2 Max
0:04:03 The Carol Bike: Efficient and Effective Exercise
0:08:42 Sprint and Recovery: The Key to Easy Exercise Habits
0:12:25 Addressing the Lack of Time for Exercise and the Inactivity Epidemic
0:16:05 The Power of Short 20-Second Sprints
0:21:02 Triggering Physiological Adaptations through Sprints
0:24:16 The Benefits of Two to Three 20-Second Sprints
0:28:35 Calorie Consumption vs. Actual Exercise
0:33:12 Significant Physiological Changes with MEDS-Z Score Reduction
0:36:36 The Benefits of the Carol Bike for REHIT Protocols
0:41:12 Personalized Workouts for All Ages and Abilities
0:45:33 Aging Process and Decline in Aerobic Capacity
0:50:27 Exercise with Specific Purpose and Long-Term Commitment
0:54:02 Zone 2 Training: Popular but Few Academic Studies
0:57:08 Enjoy Cycling with Zwift and Peloton Digital on Carol Bike
1:00:36 FTP Test: Pushing Limits and Getting Comfortable with Discomfort
1:04:15 Anaerobic workout measurement and its relation to VO2 max
1:11:25 Important Legal and Medical Disclaimer


Become the best version of yourself and get 15% off of all NED products with the code DrStephanie. Go to helloned.com/DrStephanie, or just enter the code DrStephanie at checkout.

I’m Dr. Stephanie

Part geek, part magic, and all the way passionate about being a well-lived woman.

I want to throw my grandkids in the air in my 70’s. I want to be squatting even more weight than I am now, and putting my OWN luggage in the overhead bin. Sound like weird goals? For me these are just some of the little things that represent a life well-lived.

My health is MY job – I’ll be damned if I rely on luck, ‘good genes’ or a cocktail of drugs that over promise and under deliver.

The Betty Body is my first book-baby, and a collection of what I’ve learned after thousands of clinical hours, hundreds of conversations with the world’s top experts, and most importantly…

This book is an outline of what took ME from “rock-bottom health” at 38, to being my own version of a Betty in my perimenopausal mid 40’s. A woman who is physically strong, full of energy, enjoys mental clarity, great sex and a joyful family life. Is it all roses? Of course not. But I have the stamina and tools to deal with the push and pull of life so that it doesn’t turn into chronic stress.

I want this for you too. Let’s go Bettys!