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-   -   Why do I feel slow on flat-ish terrain? (https://www.bikeforums.net/showthread.php?t=1254250)

burnthesheep 07-01-22 10:24 AM


Originally Posted by RChung (Post 22559544)
I have Matthieu van der Poel's data file from his winning ride in this year's Ronde. Here's the distribution of his cadence data:
median: 91 rpm
75th percentile: 98
90th percentile: 102
95th percentile: 104
97.5th percentile: 106
99th percentile: 109


Originally Posted by koala logs (Post 22560215)
I don't think you know that I know what I'm talking about.

The person I just quoted above you here, they do know what they're talking about. A person highly regarded within the bike/tri racing community.

I'll put it simply, you're full of BS. Same comment to you I made to another poster in the other topic..........there are those that do, then those that do not. You clearly do not.

I constantly choose to engage with posters like this because otherwise the signal to noise ratio in BF gets intolerable at best, and at worst it can lead riders who genuinely don't know yet down rabbit holes that keep them from enjoying riding as much as they could. I file this one under "misinformation".

RChung 07-01-22 10:27 AM


Originally Posted by terrymorse (Post 22560330)

A summary comment from RChung :

Um, nice comment, but that's from Stephen Cheung.

koala logs 07-01-22 10:37 AM


Originally Posted by cyclezen (Post 22560414)
Ok, so lets pick >your< best current level - doing any kind of ride... TT, hill climb, rolling loop...
And you want to 'improve'...
you accept that the studies above are accurate an applicable to you... and that the most 'efficient' cadence is somewhere around 60 rpm ish....
how are YOU going to 'improve' ???
there really are only 2 things, improve power and improve efficiency - efficiency comes from 3 factors, aero, mechanical, and 'motor' - mechanical is very minimal which includes all aspects of the 'machine/bike' (tires, drivetrain, overall weight, etc...) , aero - again somewhat equipment, somewhat ride/position, a lot of the environment (flat road vs steep hill, head vs tail wind, etc...)
...finally - the efficiency of the 'engine/motor' - can this be improved? - let's leave that for the moment...
Back to improve engine/motor 'POWER' - if you accept 'efficiency is already predefined at somewhere round 60 ish rpm - what and how do you improve the only other option open, your power?
will it be enough? you're already 35-40 yrs old (or older...) , and not as 'powerful as you were 10 yrs ago... you have many constraints on your time/ability to maximize your 'power improvement' - what's left to do to improve?
here's a great video on results of doing ONLY power based work for a period of time and the result of it, eliminating any possible change in 'motor efficiency'
https://www.youtube.com/watch?v=J4UJVeO7_eg - whoop commercial aside...
increased power enough to 'improve' actual riding over time?
... back to 'efficiency'
if you accept that 'efficiency' is within the studies' observed bounds, can there be substantial/substantive efficiency improvement? or are you limited?
OR
is YOUR engine/motor efficiency not yet at it's optimum? (not observed in ANY of the studies...)
if there's an opportunity to 'improve' your efficiency, what can/will you do to improve or define your 'efficiency' and it's limits?

Ride On
Yuri

I've been riding for 3 years now. At this point, I don't typically get any significant gains in performance, unless I did something totally different or stumbled upon a structured training program that works well for me.

One of those things that did it for me is training to raise my "preferred" cadence. Did not happened overnight though. It's a process that took at least two months.

koala logs 07-01-22 11:06 AM


Originally Posted by burnthesheep (Post 22560441)
The person I just quoted above you here, they do know what they're talking about. A person highly regarded within the bike/tri racing community.

I'll put it simply, you're full of BS. Same comment to you I made to another poster in the other topic..........there are those that do, then those that do not. You clearly do not.

I constantly choose to engage with posters like this because otherwise the signal to noise ratio in BF gets intolerable at best, and at worst it can lead riders who genuinely don't know yet down rabbit holes that keep them from enjoying riding as much as they could. I file this one under "misinformation".

I also know they do know what they're talking about.

terrymorse 07-01-22 11:29 AM


Originally Posted by RChung (Post 22560446)
Um, nice comment, but that's from Stephen Cheung.

Oops, sorry (attribution fixed above).

cyclezen 07-01-22 04:55 PM


Originally Posted by terrymorse (Post 22560330)
I think the idea behind the high cadence drills is to allow for the bursts of power needed during a race course.

A summary comment from Stephen Chung :

In the end, it appears that you can be fairly similar in efficiency and performance between the range of 80 – 100 rpm, so a higher cadence may not be as big a deal as it seems.

https://howtheyplay.com/individual-s...Faster-Cycling

S. Chung, Optimal Cadence: What’s Right For You?, 2005-02-07

You've taken the comment completely out of context. I suggest that those interested read the entire article and citation; and interpret the comments of the article themselves.
The article is interesting and an 'interpretation', the citation is a bit more straight forward and worth pursuing... so I've request a full copy of the study.
Thanks for the reference...
Ride On
Yuri

koala logs 07-01-22 08:18 PM

Here's another article about 120 rpm cadence.

https://www.roadbikerider.com/whats-...cling-cadence/

I myself doubt they really mean "efficiency" as-is. I think it's more of a combination of actual efficiency and muscle fatigue. If you're quite well trained at high cadence, you'll be able to cope with muscle fatigue better. At least that was my experience. When I attempted to do a century with previous training plan of 7 hours per week at preferred cadence averaging 70 rpm, I bonked hard. I completed the trip but felt really bad.

I maintained my 7 hrs weekly training but progressively raised the cadence while retaining the same heart rate intervals to see if things will improve and it did for half-century rides. Training for higher cadence took more than 2 months. I was averaging 110 rpm in the flats by the time I did my first century without stopping and without bonking. I did my hurt my neck because I wasn't used to riding long hours without stopping but my legs are still in good shape at the end of the trip and not fatigued. Training for high cadence does help to a great degree with endurance and delaying muscle fatigue especially if you have very limited time for training.

scottfsmith 07-02-22 09:24 AM


Originally Posted by koala logs (Post 22561112)
Here's another article about 120 rpm cadence.

https://www.roadbikerider.com/whats-...cling-cadence/

I didn't see 120 mentioned anywhere in that article, only 80-90 being optimal for serious riders.

That said I do like spinning. I average high 80s according to my Wahoo reading my pedal power meter; if you take out the standing/slowing places it is more like 92.

koala logs 07-02-22 10:20 AM


Originally Posted by scottfsmith (Post 22561478)
I didn't see 120 mentioned anywhere in that article, only 80-90 being optimal for serious riders.

That said I do like spinning. I average high 80s according to my Wahoo reading my pedal power meter; if you take out the standing/slowing places it is more like 92.

92 rpm is very good already. On climbs, I do between 80 to 95 rpm when trying to get up there as quickly as possible or 100 rpm if I want to take it easy using easier gears. Only in the flats I can sustain 120 rpm.

3rd paragraph from the top of the linked article:


Competitive cyclists pedal at an average cadence of 80 to 105 RPM and they do time trials at 110-120 RPM. If you train to increase your cadence, you will usually improve your cycling efficiency, allowing you to ride longer and faster.
And here's where the article gets quite interesting:


Why A Slower Cadence Tires You Earlier


When you feel tired and your muscles hurt on a long ride, your fatigue is caused by running out of sugar stored in your muscles. In one study, racers spinning at 50 pedal strokes per minute used up far more of their stored muscle sugar (glycogen) than they used up while spinning at 100 revolutions per minute to generate the same amount of power (Eur J Appl Physiol, Aug 2004;92(4-5):443-51) . Their bodies consumed the same amount of oxygen and had the same heart and breathing rates, total rate of power production and blood lactate levels. Interestingly, the extra loss of muscle sugar pedaling at 50 revolutions per minute occurred only in fast-twitch muscle cells that govern strength and speed. Over 30 minutes, the fast-twitch muscle fibers lost 50 percent of their glycogen (sugar) at 50 rpm and only 33 percent at 100 rpm. That means that your muscles weaken far more at 50 RPM than at 100 RPM because you are putting so much pressure on your pedals
When approaching the subject of cadence, one shouldn't just treat it as a matter of power output vs VO2 max but also in terms of fueling. Unless you can metabolize fuel at incredible speed, you'll last longer without fatigue if you spin high cadence (assuming your are also well-trained to spin high cadence). That was my own experience as well trying to do centuries with the least amount of fatigue afterwards.

Although you don't have to train to spin 120 rpm unless you see improvements in your performance and you won't be getting results overnight. Not even in a week. It would take at least one month to see anything substantial.

.

RChung 07-02-22 10:39 AM

MvdP, TDF 22, Stage 1 ITT

quantile, rpm
50, 94
75, 99
90, 103
95, 105
97.5, 106
99, 108

Sy Reene 07-02-22 10:50 AM

How much shifting does a pro TT rider do. I can obviously imagine that they train to be efficient over a wider spread of RPMs than us mere mortals, to reduce amount of shifting -- finding that a change in cadence is overall quicker than gear changes to maintain a narrow rpm range.

terrymorse 07-02-22 10:56 AM


Originally Posted by RChung (Post 22561541)
MvdP, TDF 22, Stage 1 ITT

Was that a fairly flat course?

My gut suggests that the cadence would be a bit lower than that on a hilly course.

scottfsmith 07-02-22 10:58 AM

Oops you are right about the 120 in the article .. I skimmed over that.

Hey on a related topic it seems like the apps are reporting mean cadence, not median, right? I have Strava and Wahoo apps for example. Don't you really want to know the median as there are a lot of "low" points when you are slowing down for that stop light or taking a sit-break and doing a slow standing mash. Those points will lower the "average" and skew your supposed standard pedaling speed. When I eyeball my data it looks like my median is in the lower 90s. Is there anyplace I can upload the data and I will get the median spit out? Or even better the quantiles like RChung is posting (thanks for those by the way!!).

My own cadence seems to be constant up to about a 5 degree uphill, at which point my lowest gear is not low enough and my rpms are decreasing.

terrymorse 07-02-22 11:14 AM


When you feel tired and your muscles hurt on a long ride, your fatigue is caused by running out of sugar stored in your muscles.


That's a very confident and simple explanation of what causes fatigue. The actual explanation is much more elusive:

Although it is not difficult to know when one is fatigued, it is entirely another matter to be able to identify the physiological mechanisms responsible for this condition. Despite the accumulation of a substantial literature on the topic...few principles have emerged to characterize the phenomenon of muscle fatigue. Although progress has been made in the study of muscle fatigue...we are largely unable to state with certainty why an individual becomes fatigued under various conditions.

Enoka et al, Muscle fatigue: what, why and how it influences muscle function, 2007

Sy Reene 07-02-22 11:20 AM


Originally Posted by scottfsmith (Post 22561557)
Oops you are right about the 120 in the article .. I skimmed over that.

Hey on a related topic it seems like the apps are reporting mean cadence, not median, right? I have Strava and Wahoo apps for example. Don't you really want to know the median as there are a lot of "low" points when you are slowing down for that stop light or taking a sit-break and doing a slow standing mash. Those points will lower the "average" and skew your supposed standard pedaling speed. When I eyeball my data it looks like my median is in the lower 90s. Is there anyplace I can upload the data and I will get the median spit out? Or even better the quantiles like RChung is posting (thanks for those by the way!!).

My own cadence seems to be constant up to about a 5 degree uphill, at which point my lowest gear is not low enough and my rpms are decreasing.

There's the "Elevate" plugin for Strava which is nice.. eg gives you this type of info

https://cimg5.ibsrv.net/gimg/bikefor...2fbb838975.jpg

scottfsmith 07-02-22 11:29 AM

Sweet, thanks! It looks like the apps may in fact be reporting the median.. It gives me a 50% of 89 which is my average in Strava. Here is my ride this morning .. no super steep hills so my cadence was the same up the hills.


https://cimg8.ibsrv.net/gimg/bikefor...8e2b4345d7.png

koala logs 07-02-22 11:37 AM


Originally Posted by scottfsmith (Post 22561557)
My own cadence seems to be constant up to about a 5 degree uphill, at which point my lowest gear is not low enough and my rpms are decreasing.

My cassette goes from 11t to 40t! Plenty of opportunity to spin on climbs!

RChung 07-02-22 03:55 PM


Originally Posted by Sy Reene (Post 22561550)
How much shifting does a pro TT rider do. I can obviously imagine that they train to be efficient over a wider spread of RPMs than us mere mortals, to reduce amount of shifting -- finding that a change in cadence is overall quicker than gear changes to maintain a narrow rpm range.

They certainly shift more than I do, but I don't know whether that's because they use di2 and I don't. I shift more with modern brifters and 11-speed than I did when I used downtube shifters and 5-cog freewheels so that's evidence that my shifting can be influenced by technology.

If you have both a speed sensor (not GPS) and a dedicated cadence sensor you can usually back-calculate your gear ratios from ride data, so you can see when and how often you shift.


Originally Posted by terrymorse (Post 22561554)
Was that a fairly flat course?

Copenhagen, so dead flat. There were a lot of turns where cadence dropped to zero so that's a reason not to look at mean cadence but rather the cadence distribution. That's why I looked at the quantiles.


My gut suggests that the cadence would be a bit lower than that on a hilly course.
Cadence tends to drop on hilly courses. [Edited to add:] Cadence and pedal force (or crank torque) tend to be inversely related. On climbs, pedal force goes way up but cadence drops. On descents, riders tend to shift into high gears, but at some point the benefit of additional power decreases and you're better off just coasting. Things don't even out, so overall on hilly rides cadence tends to drop.

tomato coupe 07-02-22 06:00 PM


Originally Posted by koala logs (Post 22560204)
Don't fight the mass of your legs but rather use its momentum to carry the legs around the pedal stroke like a flywheel effortlessly.

Your legs have very little resemblance to a flywheel.

koala logs 07-02-22 09:06 PM


Originally Posted by tomato coupe (Post 22561894)
Your legs have very little resemblance to a flywheel.

A flywheel is simply a mass that is moving in a circle or a mass possessing angular momentum. Parts of the feet below the knee would possess angular momentum to varying degrees when you pedal. Above the knees, we still have angular momentum but in an oscillating fashion. That oscillating momentum is also carried over to the angular momentum below the knees through leg kinematics.

Don't fight it but work with it. Do you think the pros having powerful looking leg muscles is how they were able to turn the pedals for long periods above 100 rpm? Is it really air you're breathing?:)

tomato coupe 07-02-22 10:55 PM


Originally Posted by koala logs (Post 22562041)
A flywheel is simply a mass that is moving in a circle or a mass possessing angular momentum. Parts of the feet below the knee would possess angular momentum to varying degrees when you pedal. Above the knees, we still have angular momentum but in an oscillating fashion. That oscillating momentum is also carried over to the angular momentum below the knees through leg kinematics.

Don't fight it but work with it. Do you think the pros having powerful looking leg muscles is how they were able to turn the pedals for long periods above 100 rpm? Is it really air you're breathing?:)

Sure, parts of the leg below the knee have some angular momentum. But, the bulk of the legs have almost no angular momentum. Overall, the legs are very much not like a flywheel.

koala logs 07-03-22 02:12 AM


Originally Posted by tomato coupe (Post 22562090)
Sure, parts of the leg below the knee have some angular momentum. But, the bulk of the legs have almost no angular momentum. Overall, the legs are very much not like a flywheel.

All the momentum in the legs whether it's angular or linear momentum must be conserved or else it will violate two of the most fundamental laws in physics, the law of conservation of energy and also the law of conservation of momentum.

When the upper leg motion makes two brief stops at each end of its up and down motion per crank revolution, that momentum doesn't just disappear and is totally gone. That linear momentum is transferred to the lower leg mass through the knee joint and becomes angular momentum.

That angular momentum from the lower leg is again transferred back to the upper leg via the knee joint as linear momentum as the upper leg moves away from each end of motion. These back and forth transfer of momentum between the upper leg and lower leg and vice versa happens twice per crank revolution.

You don't need to have heavy "flywheel mass" to have efficient transfer of momentum in a leg type mechanism driving a crank. If the flywheel is light, it would speed up more to absorb the same amount of linear momentum being passed to it. A light flywheel would simply oscillate in rpm more dramatically than a heavy flywheel in such application but still perform its job with the same level of efficiency.

The good news is most of us already work with the leg momentum when we pedal. No one's really fighting against it. Any difficulty we feel at high cadence is simply due to different muscle adaption (which can be changed through training) and the "anti - placebo" effect. Thinking of a problem that isn't really there.

tomato coupe 07-03-22 03:02 AM


Originally Posted by koala logs (Post 22562145)
All the momentum in the legs whether it's angular or linear momentum must be conserved ….

Your understanding of how conservation of momentum and energy works in regards to the movement of one’s legs is incorrect. Energy is conserved, but the kinetic energy of the legs is not conserved. Momentum of the legs is also not conserved in the presence of losses.

koala logs 07-03-22 05:26 AM


Originally Posted by tomato coupe (Post 22562153)
Your understanding of how conservation of momentum and energy works in regards to the movement of one’s legs is incorrect. Energy is conserved, but the kinetic energy of the legs is not conserved. Momentum of the legs is also not conserved in the presence of losses.

Energy is always conserved:

https://www2.estrellamountain.edu/fa...20to%20another.

Momentum is always conserved as well:

https://www.grc.nasa.gov/www/k-12/ai...%20of%20motion.


Believe me if you know a way to violate the conservation of momentum, NASA would be banging at your door! "Bending" that law is the key to interstellar travel.

I agree with you about the losses but the losses mainly comes from the internal friction within your legs, within the body, interface losses like in the saddle and footwear, and any inefficiencies in the pedaling technique. The raw movement and momentum of your legs is never the source of resistance unless your pedaling technique is totally messed up which is unlikely.

Another source of "perceived loss" is pedaling at a cadence you're not used to. You can always try training at other cadences to see if you can net some gains.

tomato coupe 07-03-22 09:53 AM


Originally Posted by koala logs (Post 22562191)
Energy is always conserved ...

The total energy and momentum of a (closed) system is conserved. The kinetic energy and angular momentum of any given entity, e.g. your legs, is not conserved in the presence of losses.


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