2 min read

Next-level HIIT

CAROL’s the only bike with REHIT, the next-level HIIT workout that gives you double the health benefits, in just 10% of the time.


Reduced Exertion HIIT (REHIT) was developed by scientists looking for the shortest, most effective and accessible way to exercise.

Research proved that REHIT is the fastest way to get fit, with short workouts that fit any schedule. But there was a catch: true REHIT was only possible in the lab.

We teamed up with the world's leading exercise researchers to get REHIT out of the lab—into the real world. And 40 prototypes later, CAROL launched the world’s only home REHIT exercise bike.

“CAROL is the only bike that accurately replicates REHIT outside of the labs. This scientific exercise cannot be done on a regular bike because it requires the supra-maximal resistance tailored to each person’s physiology.”

Dr. Niels Vollaard

PhD, Exercise Physiology Researcher, University of Stirling

Read the full study here.