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How to hack your cardio

5 facts about cardio, discussed by CAROL CEO and co-founder, Ulrich Dempfle, and Dave Asprey—on The Human Upgrade podcast.

More isn’t necessarily better

You don’t get fit while you workout, you get fit in the recovery between your workouts. The workout just has to provide the stimulus and with Reduced Exertion HIIT (REHIT), you can create the most powerful stimulus with just 40 seconds of maximum effort, split into 2×20-second sprints. All you need is 5 minutes, 3x a week. 15 minutes total. And it’s scientifically proven to be the most effective workout.

Beyond 2×20-second, it doesn’t matter how long you sprint. More or longer sprints don’t have additional benefits. It’s like flipping a switch, pressing it longer doesn’t have more impact. What matters is that you sprint at your personalized maximum intensity, switching from zero to max in a fraction of a second.

Cardio fitness impacts longevity

Many people think of exercise as a way to lose weight, but that’s only a small part of it. You’ll live a longer and healthier life.

VO2max is the main measure of fitness. The higher your VO2max, the fitter and healthier you are—and a 10% improvement in VO2max adds 2 years of healthy life expectancy.

VO2max declines by about 10% every decade after the age of 30, but effective cardio training can reduce the drop in VO2max to 5% every 10 years. CAROL Bike increases your VO2max by 12%–in just 8 weeks.

Menstrual cycle impacts performance

For women, the menstrual cycle has a strong impact on athletic performance. They are at their peak performance halfway through the follicular phase. So much so that professional athletes time their period so that they are in peak shape for competitions.

Consistency is key

Less than 5% of the population meet recommendations for aerobic exercise. And the number one reason given is lack of time.

Exercise is like diet. You can build a surprising amount of fitness in only 6-8 weeks, but if you don’t stick to it, you will also lose it again as fast as you gained it. So you need something sustainable that fits into your life no matter what.

CAROL saves you more than 2 hours a week on your cardio. Instead of the recommended 150 minutes, all you need is 15 minutes.

A 5-min workout, 3x a week. Habit-forming numbers that work.

Maximizing calorie burn

HIIT and Reduced Exertion HIIT (REHIT) workouts will help you burn more calories than steady-state exercise, such as normal cycling or even strength training.

Research by the Western University Colorado shows that you’ll burn more calories on a 15-minute CAROL Bike ride, than a 30-minute run.

Get Fitter


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Live Healthier


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