Endurance Nation | Triathlon Coaching, Ironman Training, Half Ironman, Beginner Triathlon

@Mike -- Coach P here as R drives up the 5 to NorCal for the clinic. Thanks for the comment...if we gotta put ourselves out there with what we believe to get feedback, we will do it! Neither one of us disagrees with what you are saying re an "optimal" cadence that allows the rider, given her strength, muscle fiber types, the current terrain, conditions, her cumulative fatigue, etc, to travel at a faster rate of speed than another cadence. (IOW, when I am shelled and try to ride at 90 rpms.) Rich's point is that the gearing itself doesn't _make_ you faster; rather optimal gearing will enable your muscles, in the given conditions, to put the best possible sustainable power to the road. But my 12/27 didn't move my bike; my legs did.

As another example, we never leave the house saying, "Today I will ride at 88rpms!" I do, however, think about the wattage I will be riding at; as my body/legs create that wattage. IOW the watts are what matter as a benchmark to monitor, train to, and improve.

In our world view, speed and cadence are outcomes of (A) how hard I am asking my body to work and (B) for how long.

IMO, by the time someone owns a PM, they have already developed a personal optimal cadence selection process. A PM highlights the costs associated with our gearing choice given the performance demands we are placing on our body, but that's it. IOW, inside EN, I would advise folks to shift around to find better watts, not a better cadence.

I have drank of virtually all of the EN cool aid but I don't know about this one in entirety. Mike I think you are own to something here.

Two bikes traveling at the same speed with the same effective weight and rolling resistance are utilizing the same functional power. However, I think the fast twitch slow twitch muscle scenario comes in to play.

I turn 80 rpms, if I turn 40 rpms on the same 12% grade hill I will "Blow up" but if I turn my same 80 rpms I chug straight up the hill.

Why? I think it is because I recruit different muscles for the two rpm levels. Can I train to turn 40 or even 110 rpms, yes. Do I need to train with that much variation?

Coaches I need more koolaid because I am not smart enough to answer that question.

OK, geek alert here. But I've gotta do it.

I agree with the fundamentals of what you're saying. However, there's a basic biomechanics phenomenon you're ignoring which needs to be considered. It has to do with the force-velocity curve in the muscle.

We agree that fitness is in the muscles. We agree that going x miles per hour (under controlled conditions) means you're doing Y watts. But one rider can be working harder than another, because muscles produce force, not watts. The force a muscle can put out is a function of how quickly it is contracting. Quicker contraction, less available force.

link to quick force-velocity primer
http://www.sportsci.com/sports...

Because of the shape of the curve, power is optimized at a particular contraction velocity (RPM). This is a trainable phenomenon.

So, no question, we want to go faster on race day, and speed is the final arbiter. But, perceived exertion based on different cadence is not just between the ears. It can also be in the muscles.

In other words, gearing is more than just a transmission. It can also influence the engine.

-MG