Back on the CAROL bike - an example of slope-of-the-curve biology

In Smarter Not Harder, Dave Asprey discusses the concept of slope-of-the-curve biology. For math nuts, this refers to the derivative as opposed to the integral, which represents the area under the curve.

For the longest time, we have been told that area under the curve is what matters. How many reps, how much weight, and how long you perform exercise. It turns out that the body responds better to the slope of the curve–how fast you increase and how fast you return to baseline.

The perfect example is the CAROL bike, which I was lucky to win at the Biohacking Conference in Orlando. This is no ordinary stationary bike. The CAROL bike uses a concept known as REHIT–reduced-exertion, high-intensity interval training. This type of training works because it causes rapid glycogen depletion, which triggers signaling molecules and increases mitochondria.

You start with a two-minute warm-up where you pedal as slowly as possible. You do not want your heart rate up; this is just a lazy stroll. Then you do an all-out, balls-to-the-wall sprint for 10-, 15-, or 20-seconds. The bike uses AI to apply variable resistance during the sprint. By the end, it feels like you’re pedaling through sand. You drop back down to a leisurely pace for three minutes, then do another sprint. The final three minutes are a cool-down, and the exercise is done. A great workout in less than nine minutes!

Why is REHIT better than standard HIIT? Studies show that regular HIIT requires such long recovery periods it isn’t as time efficient as it is often claimed to be.

I have been derelict in using the bike for several months, and now it’s time to get back on the horse.