recursive

Most people here are using clipless pedals, which do attach one's shoes to the pedals.

Debusama

Right, but from a physics standpoint; inertia being an objects resistance to changes in velocity, it is much more relevant to accelerating up to speed than it is to maintaining a consistent speed. Why would inertia of the flywheel affect the cadence at which I am able to comfortably produce the most power?

StanSeven

Thanks. That is really helpful and informative.

RChung

Because the wheel speed isn't consistent and our legs don't produce constant torque. Max torque (or pedal force) is higher than average torque (or force), and on most trainers the rotational inertia is only a small fraction of the translational inertia we experience on the road.

hyhuu

Wut???

revchuck 

The problem isn't with the red herring of cadence, but with the strawman you're creating. I'm not aware of anyone who writes professionally about training who even implies that one's cadence should be "x" in all conditions. Rather, it's presented in context, whether it be on the flat, on hills, sprinting or otherwise, because these all require different cadences at different times. In my experience, the same thing occurs over coffee/beer/whatever in informal conversations after a ride.

It is an issue that needs to be discussed with newer riders, because there is a sweet spot for each rider where the best balance between cardio and muscle effort occurs, and yes, it does vary among cyclists and is further fitness- and situation-dependent. Ignoring the whole issue, which you seem to imply to be the way to handle it, would be a disservice to a new rider.

wrr1020

I usually average 90-95.

contango 

Depends how I'm feeling on the days I ride. Some days I keep the cadence somewhere around 50-60 (estimated) and let my leg muscles do the work. Other times I keep it higher, I'd reckon 80-90, and get a bit of a CV workout. Some days I chop and change. I used to try and mash my way up hills and did it for a while (being a heavy guy it's easy to put a lot of weight on the pedals) but soon found that if I misjudged a hill I'd power up the first part and then burn out, so when I encounter a hill I constantly remind myself to just keep the pedals turning smoothly rather than mashing.

RChung

OK, then, since those cadence recommendations are presented in context, can you show me examples where "sweet spot" recommendations are given for the power and crank torque that each rider should use? We know that power = cadence * crank torque (* a constant) so the context should be either power or crank torque. If you don't give a recommended crank torque (or power) whenever you give a recommendation about cadence, that would be a disservice.

SPlKE 

85-105

I aim for 95-100 on long flats.

revchuck 

The context within which this is presented concerns the activity - climbing, sprinting, time trialing, etc. Specific cadences aren't given, but ranges. Your arbitrary introduction of a locked-in power/cadence standard would work only in a theoretical world where all cyclists are identical. Tom Boonen and I might both like to cruise with a 90 rpm cadence, but there would a huge difference in power (and speed) between us. The "sweet spot" varies among individuals, and even with an individual it will vary based on fitness and other factors. We all find our own eventually.

This needs to be discussed with newer cyclists because pedaling at a higher cadence (~90 rpm) is counter-intuitive. Almost all of us grew up pedaling our bikes relatively slowly as kids. Pedaling slowly puts the majority of effort on our legs; pedaling quickly puts the majority of effort on our cardiovascular system. Somewhere between the extremes, usually in the 85-95 rpm range, is where most of us find our sweet spot.

rangerdavid

85-95 usually. When I was starting out, that rpm seemed really fast to me. now my max is around 115, that being the point at which I start to bounce in the saddle. As my legs get stronger, I think I'll be able to hold that and hopefully up to 120 or 125 without bouncing.

RChung

Cool. So you're saying you *do* give pedal force or crank torque recommendations to new riders along with the recommendation that they pedal at 90+ rpm. So, here's a simple question: for a new rider, what pedal force in N or crank torque in Nm recommendations do you give?

svtmike

As much as you want to point to C A-S's data and say cadence is a red herring, you can clearly see that when he's climbing he turns over at about 80 rpm, and when he's cruising he turns over the pedals at around 90 rpm. Of course there's variability to the data, but there are very clear clusters of data there.

Every cycling coach I've seen/spoken to/read has specified a target cadence range for certain activities. Climbing is typically recommended at 70-85 rpm, cruising 85-100rpm, and attacking/sprinting > 100rpm. There's nothing inconsistent in the data that you posted with these very common cadence range targets.

garciawork

I average 99 on flat rides, but with no big hills or stops, I usually have to think to stay below 110. I don't understand why my body wants to pedal so fast, I feel like it could be tiring my lungs out more, but oh well.

wkg

oxygen is (sort of) unlimited keep it up

RChung

Every coach? Hmmm. I've certainly seen/spoken to/read coaches who don't specify a cadence range like that. I think you need to see/speak/read more coaches. Do all your coaches specify a target pedal force range or power output for certain activities? You know, "Climbing is recommended at X watts, cruising at Y watts, and attacking at Z watts"? If cadence * crank torque (* a constant) = watts, why do these coaches recommend the same cadence range for guys whose FTP is 200 watts and guys whose FTP is 400 watts? If you look at other racers data files, you'll see that freely-chosen cadence varies with slope -- typically, the steeper the slope the lower the cadence. Your coaches, do they say "when climbing an X percent slope you should use a cadence in the range of THIS but when climbing a Y percent slope you should use a cadence of THAT"?

svtmike

Of course not. But they do specify a percentage of FTP that they want the effort made at. Oddly enough, the coaches' recommendations coincide with freely chosen cadences -- lower for climbing and TTing (where efforts are expected to be prolonged, intense, and easy to overshoot), higher for attacking and cruising.

Perhaps what you're missing (or refusing to accept) is that cadence is a trainable adaptation -- your "freely chosen" cadence today might be much lower than your "freely chosen" cadence after a couple years of training focused on a smooth, higher pedal cadence.

I think you need to lose your obsession with the idea that anyone anywhere would specify to riders in general that they should be riding at a particular absolute pedal torque or power level because you're the only person I've ever heard propose such a ridiculous thing (and you do know that it's ridiculous, I realize that).

RChung

Wait a sec. You're saying coaches specify a cadence that coincides with the freely-chosen cadence? Hey, I agree with that -- and so do several of the coaches that I know. They recommend (as do I) that riders focus on developing the power level that they need and use their gears so that they can produce that power in as comfortable a fashion as they can (given that producing 400 watts isn't really all that comfortable).

Well, perhaps so. I said quite often (and many coaches now agree with me) that I don't think cadence in isolation is a particularly trainable adaptation. As I've pointed out, cadence responds to the level of power, the gradient, crank inertial load, and the gears you have available to you. What that means is that *if* you're going to train cadence, it can't be in isolation; *if* you're going to train cadence then you should train it in the context of power and gradient and gears. Or, you can do what I (and some coaches) recommend: focus on developing your power and use your gears to produce that power as comfortably as you can. Training high cadence at low power isn't a particularly "targeted" way to develop the ability to produce high cadence at high power (and the same applies to crank torque or pedal force).

Oh, I agree it's ridiculous. No one makes recommendations like that -- but it's important to understand that there's nothing special about cadence that doesn't also apply to crank torque (or pedal force). It's just as ridiculous to make cadence recommendations in isolation as it is to make crank torque recommendations in isolation; yet people make cadence recommendations all the time without making crank torque recommendations.

Here, btw, is another plot for a hillclimb. Sorry if it's a tad small -- it was what I had handy. It shows the crank torque and cadence Rory Sutherland produced during the end of Stage 4 of last year's Amgen Tour of California. He finished that stage in 3rd, in the same time as Andy Schleck and Levi Leipheimer. Note the relationship between cadence, power, and crank torque. Which is more closely correlated with power, cadence or crank torque?

svtmike

Not sure what that chart is supposed to prove -- there are two independent variables for the rider (cadence and torque), and power is dependent on both of them as you know.

Since power is a mathematical derivative of torque and cadence, it therefore should (and does) show a correlation to both of them. Given that Power = Torque x RPM, there shouldn't be a stronger correlation between power and either one of them; if you calculate out the correlations they should be mathematically equal at 1.0, no?

gerundium

Fail? Power torque and RPM are by mathemical derivation correlated variables. don't call out someone with a statistic when all you are showing is that you haven't thought it through.

P = M*V (V = rotational velocity dtheta/dt in this case and M is net torque)

what we are seeing in this chart (most likely) is that Ctorque is measured by a device (strain gauges, a.k.a a power meter) and from that power is calculated. if RPM is measured seperately we can cause spreads like this from measurements not syncing up etc. by theoretical analyses though these variables should all be correlated.

fstshrk

My cadence is range is 70-110. I average around 82-85 and can drop to 70 or so on tough climbs. Any lower and my knees start hurting.

RChung

Well, I'm starting to see the problem.