RChung

Good idea. I could've assigned him some of my homework problem sets. And then graded harshly.

tomato coupe

Remember, you just want to put him in his place, not humiliate him.

Troul 

trying to sustain a MAX cad is where I expect it to be no more gooders.

The ticker couldn't tolerate a MAX output before it beats itself up.

79pmooney

Downhill on a fix gear. I"m not superman!

We should keep in mind that this discussion really only matters for a rather small range of RPMs. 80-120. (Really 90-110.) Yes, some of us ride outside those limits but racers only do uphill, especially when gear limited like the old days and briefly when very high powers are needed (or on the track - again, gear limited).

What isn't being discussed here is what bodily resources are being consumed by riding at these different rpms. Low rpms - the ability of the muscles to keep applying that force, and more important in races, higher forces and rpms later when it matters. High rpms - more energy expended. With smart eating and replenishment, this can be offset to a degree but the ability to do so must be trained on. And - very important, different riders have different abilities at both of these (not radically different rpm-wise) extremes.Heavier and more muscular riders will be less efficient at high rpms. The skinny guys wear themselves out trying to lug the lower rpms but can spin the fast stuff relatively easily.

Conversely, low rpms don't drain the body as rapidly of sugars so more is 'in the tank" at the end. The spinners have less fuel but their muscle fiber hasn't done a whole lot and is ready to handle a few minutes in that big gear. And again, different bodies have different tank sizes and cylinder volumes (to use car analogies; smart drivers drive the race with what they got).

There are other factors too. One is not often discussed - although its biggest advocate benefited greatly from it - oxygen performance enhancers. That advocate? Lance Armstrong. (Well, he never came out and said anything until long after, but his performances were a stark tribute to EPO's oxygen uptake improvement and therefore ability to ride those higher rpms to advantage.) He was not a spinner who could ride the world off his wheel up mountains before EPO. It would be fun to see a study of what happened to average rpm over the EPO years and see if it has settled down some since.

PeteHski

Modern road racing pros seem to favour the 90-100 rpm range as an average riding cadence. I don't think there is very much variation amongst them. They sprint at 120-130 ish rpm and may cruise along down in the 80s when not trying. There is probably most variation in their climbing cadence. Some spinning above 100 rpm, others considerably lower. Probably more gear and W/kg related in that case. The lightweight mountain goats are inevitably going to spin a higher cadence than the sprinters up a mountain pass in the same low gear i.e. riding faster.

Hour record attempts are typically in the 90-100 rpm range too, usually at the higher end. Ganna averaged 98 rpm when setting the latest record.

livedarklions

You're postulating a 150 rpm cadence. That's basically a reductio ad absurdum extreme. I don't think it's unreasonable to assume someone pedaling at that rate is doing so at a very low gear.

I actually push the reductio ad absurdum high gear for hours at a time. For my legs, it's very efficient. I'm not built like a racer, so racing technique generally doesn't apply to me very well.

PeteHski

Just for clarification, are you talking about peak sprinting power (e.g. 3-sec duration) or maximum sustained power (e.g. 1 hour duration)? The latter makes more sense relative to my own cadence and torque limits. My cadence limit without bouncing like crazy is approx 160 rpm (achieved for a few seconds only during low power cadence drills) and my 1-hour best power is achieved at a cadence of around 85 rpm. So that ties up very well with your statement above. However, my peak sprint power is attained at 100-110 rpm (I'm not much of a sprinter btw). So considerably closer to my max cadence. Could I possibly spin at 220 rpm? I suppose maybe I could if I trained myself, but 160 rpm is certainly my current limit without losing control.

RChung

Until very recently, most hour record attempts were done above 100 rpm. Obree was an exception, at below 90. If you look around on the intertoobs, lots of riders, including coaches who advised high cadences for those of us with more plebian abilities, would say, "it's no coincidence that hour records are set at 105 rpm."

I was talking about max output, not sub-maximal. Most (many?) of us have max cadence somewhere in the range of 200 to 250 rpm, so max output is rarely achieved at more than 120ish rpm. That said, if max output is produced in the range of 120ish, there's really no reason why sub-max (considerably sub-max, in the case of 1 hour duration) should be higher than that. For many of us, max output may be 500% or 600% of our "threshold" power, but power-maximizing cadence isn't 5x or 6x "threshold" cadence.

Because of gearing, when we look at cadence across individuals, slowish individuals may have cadences about 75% of faster spinning individuals. OTOH, lower power individuals may have output that's a third of more powerful individuals. There's far more variation in pedal force across individuals than there is in cadence. Cadence is a red herring. I tend to use cadence prescriptions as an indication about the prescriber.

PeteHski

This is quite interesting thanks. Why do you think hour record cadence has recently trended a little lower? I remember reading about Joss Lowden running a relatively low cadence for her hour record i.e. 90 rpm. I'm far more interested in sustained power than maximum sprint power (as an endurance rider).

My FTP is around 75% that of an average Pro (although W/kg more like 70% or less as I'm not as lean), but my cadence is probably within 10% of typical Pros. So I get your point about pedal force variation across riders, but I'm not sure I agree with your statement about cadence being a red herring. My untrained cadence was significantly lower than it is today and I definitely gained both power and endurance from training with a higher cadence. Untrained I was generally riding at around 75-80 rpm at tempo, now I'm up in the high 80s to low 90s average. So I'm fairly convinced that training to push your cadence a little higher is of significant benefit. That's not to say I don't work on the pedal force side too. For me they are both important if your aim is to improve power output.

RChung

I think Ganna used taller gearing than many others would be able to. But I also think there are aero drag reasons both to use shorter cranks and taller gearing (which decreases pedal speed even more). Shorter cranks can improve positioning, and lower cadence can improve drag (ceteris paribus) because the legs churn the air.

I had edited my post to observe that for an individual, max output is typically 5x to 6x higher than "threshold" or "cruising" output but cadence at max output isn't 5x to 6x greater than threshold cadence. Your power has increased but your cadence almost surely didn't increase proportionately, so your pedal force increased also. You're pedaling faster because your power output is higher -- but there's a limit to how high your cadence can realistically go. Cyclists have been racing since there have been bikes but for most of the intervening time they've only been able to observe cadence, not power or pedal force, so cadence was the thing they fixated on. This is cargo cult: they imitated the thing that they could see fast riders doing but they couldn't see the underlying pedal force or power. That's why cadence is a red herring. It's mostly a dependent variable, not an independent one.

Carbonfiberboy 

Wow, this thread got all crazy. The answers are there, sort of subliminally in all the various posts. The theory is pretty simple: at the same speed, higher cadence = higher O2 consumption, lower cadence = higher leg force. There's always a balance to be found between these two, which will vary with the individual rider's physiology, the length of the ride, and the incline of the road. There's no right answer for everyone. Hence the reason that Lance spun 110-115 TTing was that he was on EPO which increases aerobic ability, and thus biases the rider toward higher cadence. We see the same thing in modern pros. Better aerobic ability means your legs don't get as tired and you slaughter your opponent near the top of the climb.

That said, to best exploit both ends of the cadence range, one needs to do some low cadence high effort work as well as high cadence low effort work. One should be comfortable all the way from 50 to 120 cadence, and both ends for say 30' at a time. Low cadence work will give your legs more endurance and high cadence work will reduce the amount of wasted effort in your pedal stroke at all cadences.

Having done that work, you'll find that there's a perfect cadence for you for all occasions, and it'll be different for each. The trick is to acquire the experience though experimentation to figure out what cadence to use when. When I ride, I watch cadence, power, and HR, in that order. I almost never look at speed. I'll watch elevation on a really long climb. Watching cadence is all about efficiency at the desired effort level, which is a major goal on most of my rides. It took me years of experimentation to figure out when to use what cadence.

As to why the Big Guy used a low cadence, maybe it's because he was a big guy and high cadence would have cost him too much oxygen? Do we know his VO2max compared with Lance, both juiced? Or maybe he just never trained outside his comfort zone? He was definitely lazy for such a high performer.

livedarklions

This is one of those pieces of conventional wisdom I hear all the time that is just obviously wrong--that torque doesn't vary much from person to person so focus on cadence. It's obviously absurd as it's incredibly easy to see how much leg strength varies from person to person in anything involving weights. Why would pushing pedals be any different?

tomato coupe

Who is making that claim?

livedarklions

No one in this thread, and I don't want to dredge anyone up. It's definitely something I've been told more than a few times, but you'll just have to take my word for that. Or don't.

Lots of people say a lot of dumb stuff.

Troul 

times like these are why I'm glad I don't get off into reading a lot. Rather go huff wax chain lube.

tomato coupe

Got it.

PeteHski

That is not "conventional wisdom" where I live and ride. Maybe a very old-school myth I've never heard before?
As for pushing pedals, it's different from static weight training in that you are generally nowhere near your typical "10-rep" muscle force that you might push in the gym. You are pretty much always limited by your aerobic performance in cycling, not your outright muscle strength. Dr Andrew Coggan discusses these differences in his books. That's not to say strength training isn't beneficial for cycling. Just that the muscle loading is very different.

livedarklions

I'm thinking that it is some old school thinking, and I'm very glad to hear people aren't saying this much these days. In principle, though, I think we've all been saying that the aerobic limits are less important if you can push a big gear. That's the trade-off we've all been discussing.

PeteHski

Interesting points. I can see what you mean about cadence being a dependent variable on a single-speed bike, but multiple gearing allows you to effectively select your cadence for a given power level. My cadence is limited by HR and muscle coordination. If I spin at 130 rpm for a few minutes, even at modest power, then I find my HR soon hits threshold and I have to focus to avoid bouncing in the saddle. It's really not comfortable or sustainable for me! My pedal force on the other hand is limited more by muscle fatigue. Ultimately I try to work on both increasing cadence and pedal force. I've found 85-90 rpm to be my optimum cadence at threshold power (it's about the limit where I can keep control of my HR). If I drop below 80 rpm at threshold power then I feel more limited by muscle fatigue after 20 or so minutes and I start to bog down. So it's clearly a balancing act. Out on the road I tend to vary my cadence periodically and give it very little conscious thought!

PeteHski

Cycling is primarily an aerobic sport.

Doge

I don't think how you pedal matters much.

Trakhak

You forgot to do a mic drop.

Carbonfiberboy 

Thanks. You gotta do your high cadence work indoors, using itsy teeny gears. Well, small gears anyway. Bouncing in the saddle is the wasted energy I mentioned. Bouncing means you're not keeping your pedal force tangent to the pedal circle, i.e. you're still pushing down at the bottom. (Newton's 3rd law). Don't do that. Anyone under say 65 should be able to pedal at 150, no bouncing. The trick is to wiggle your toes and think "pedal with your uppers." Yes, focusing helps. I've always done a fair bit of my training indoors so I can concentrate on what I'm doing without worrying about getting killed. After a while your ganglia mostly take over the mental load.

Back when I was strong and could easily do what I'm talking about, I used 45-50 g.i. at maybe 90 watts, 116-117 cadence, 45' no breaks. Didn't have power then. Now, I'm limited to ~110 cadence, g.i. don't much matter - I'm using 23 g.i. . I still do the drills though. Helps. Even staying below VT1, 45' of 115-120 will totally waste your legs, even after a few months of once-a-week drills. Wasting your legs means it works, as does being able to do it longer every week. As mentioned, pedal force isn't a big issue, though oddly enough, weight training does help. Lance did have to train to do what he did.

RChung

Here's a plot of a rider doing a hillclimb on a multi-geared bike. The top left panel shows the relationship between cadence and power, the top right shows the relationship between crank torque and power. I'd say the correlation between cadence and power is lower than that between crank torque and power. The bottom panels show the same thing: the relationship between cadence and crank torque, though the bottom right also shows the power level. As you may be able to see, there's a (weakly) negative relationship between cadence and crank torque. I'm not saying that cadence is exclusively a dependent variable; I said it's mostly dependent. I think that one mostly tends to decide on the power or crank torque or pedal force or effort that one wishes to put out, and you then use gearing to to help you do that. That's why the relationship between power and crank torque is closer than between power and cadence.


cadence and crank torque during a hillclimb

wolfchild

Just ride and don't worry about your cadence.