Pedaling at 60 RPM (revolutions per minute) or at 90 RPM during an uphill course: what are the effects on performance, tiredness and recovery? 

 

At 60 RPM it takes 1.0 second for the crank to make a complete revolution (360º), at 90 RPM it only takes 0.66 seconds that is 34% less. 

The contraction time of the muscles involved in pedaling, decrease thus of that same percentage. 
During the muscle contraction phase, blood flow (and so the oxygen carrying) to the single fiber, especially the most profound ones, lessens because of the increased pressure within the working muscles. 

Moreover, in terms of equal power output supplied by the cyclist, a cadence of 60 RPM requires a 34% more of applied force to each push on the pedals, compared to a cadence of 90 RPM. This means a heavier load for muscles, tendons and lower limbs-lumbar joints. 

It is easy to realize the advantages of a more “agile” pedaling cadence, especially when the rider is busy with an all-out effort, as soon as the oxygen carrying becomes the limiting factor of his performance. 

Also the recovery between 2 or more efforts, within just one training session or race, or even within the next days, takes advantage from an agile pedaling cadence, whereas the risk of injuries or overworking lesions increases with lower RPMs. 

A high pedaling cadence also improves the pumping function of skeletal muscles, the most important factor in defining systemic venous return of the blood to the heart. 
This peripheral pump plays a critical role in circulatory functional 
capacity, and can be viewed as a second heart.

 

In conclusion, high pedaling cadences are favorable to riders, as demonstrated by the examples of great champions such as Miguel Indurain and Lance Armstrong. 

A very long training as well as specific sessions are needed in order to learn how to pedal comfortably and profitably at high cadences, particularly during climbs: but that is a different story.