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Correlation between maximum leg strength and smooth pedaling

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Correlation between maximum leg strength and smooth pedaling

Old 01-25-24, 02:07 PM
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Originally Posted by PeteHski
That’s a bold claim and highly unlikely. Do you have any examples of such an obvious oversight?
Sure. Compare the pedal force graphs in the links you just published to the pedal force graphs in https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10019633/ (a better link to the PLOS published study). As we see, it's more informative to see the total BB torque than the two separate pedaling graphs.
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Old 01-25-24, 03:05 PM
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Carbonfiberboy I do NOT do ANY pedaling drills. When I started in 2007, yes, I did one leg, max spin ups and low power cadence ladders. Maybe the first couple years as I remember as part of warmup.

My one hour duration analogy was to show that to make pedaling drill "material", the duration would have to be long. Look, if one wants to do pedaling drills as part of a warmup, sure, why not. If someone has an injury, a pedaling drill may be very useful. I do not find them material to my results and I am unwilling to put any real amount of time into them. Do you remember Power Cranks? Gone. Did they work? Who knows?
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Old 01-25-24, 04:01 PM
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Originally Posted by Carbonfiberboy

And that's the reason I persist in doing this stuff on my light rollers - no flywheel effect. IMO the addition of flywheels to trainers to give them a more road-like feel is a mistake. Why not just ride on the road? For me, the purpose of a trainer is to train, not to have what most riders might call fun. Though I suppose if one were unfortunate enough to live in a area with no hills, also having a road-like trainer or just one with a variable flywheel effect might come in handy.
I know you like rollers, but this is getting silly now!
At no point does having a realistic road feel on my trainer seem like a mistake!
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Old 01-25-24, 04:50 PM
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Originally Posted by Carbonfiberboy
Sure. Compare the pedal force graphs in the links you just published to the pedal force graphs in https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10019633/ (a better link to the PLOS published study). As we see, it's more informative to see the total BB torque than the two separate pedaling graphs.
Well actually they both have their uses and plotting the left/right forces does not imply that analysts are unaware of their combined effect on crank torque.
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Old 01-25-24, 06:37 PM
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Originally Posted by Trakhak
Thanks for the links and data. This thread demonstrates yet again the truth that science was invented to rescue humanity from common sense.

Edit:

On the other hand, having poked around on line for science v. common sense discussions, here's a Scientific American piece arguing that common sense tends to be unfairly (and, often, misleadingly) denigrated in scientific circles.
It is said that “in my experience” are the three most dangerous words in medicine.
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Old 01-25-24, 07:42 PM
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Originally Posted by PeteHski
I know you like rollers, but this is getting silly now!
At no point does having a realistic road feel on my trainer seem like a mistake!
I don't mind being called a nutcase, really! Been out of the box all my life. It's just that the weird things I've been talking about are much harder to do with no crank inertial load and harder is better. It's one of the interesting things about cycling that so few pay attention to, or maybe even know about (present company excepted) that inertial load goes down on climbs, the steeper they are. And the weaker one is, the slower one goes and the lower that load is. Crank inertial load makes a difference in the pedal stroke of everyone, as has been well documented. That said, it makes a smaller difference for pros who climb 8% at 16 mph. Me, I climbed 8% at 6 mph, 132w, back in '19, with about 8500' of climbing behind me.

My thing has always been endurance rides with lots of climbing, mostly because that's the terrain around here. Being one of those with not much aerobic talent, I've had to figure out how to keep up with the younger and better riders for decades. Last time I measured my FTP, back when I was still riding well, it was 164w. There it is. I've been the fastest person in my age group on RAMROD for years. WTF. Hoping I'll get well enough to ride it in '25, when I'll be 80 and have a chance at bib #1. Then I won't have to do it again.

That said, I can totally understand why you like your trainer the way it is.
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Old 01-25-24, 08:31 PM
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I’m very glad you’re here, CFB, and I always appreciate your perspective.
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Old 01-25-24, 09:28 PM
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Originally Posted by Hermes
Carbonfiberboy I do NOT do ANY pedaling drills. When I started in 2007, yes, I did one leg, max spin ups and low power cadence ladders. Maybe the first couple years as I remember as part of warmup.

My one hour duration analogy was to show that to make pedaling drill "material", the duration would have to be long. Look, if one wants to do pedaling drills as part of a warmup, sure, why not. If someone has an injury, a pedaling drill may be very useful. I do not find them material to my results and I am unwilling to put any real amount of time into them. Do you remember Power Cranks? Gone. Did they work? Who knows?
I was saying that this is supposed to be a strength training thread and I purposely have done and do those drills with effort and durations which make them strength rather than endurance workouts. IOW, I do them to exhaustion over relatively short periods of time, whether its OLP, FastPedal or low cadence climbs. For endurance I ride outside. If one thinks these are warmups one isn't going vaguely hard enough.

I don't know why you think strength work is not material. The FastPedal drills can take more time than most strength workouts, but If I'm holding a cadence which is as fast as I can spin at low load, when I get off the bike I can hardly walk even though it was just HR zone 2. If that weren't true, I'd have pedaled faster. I had a Cat 1 trackie for a spin instructor for a while. He could hold 200. As I said somewhere above, if you're not crying for your mommy doing this stuff, you aren't going hard enough.

Depending on the drill, either a lot more resistance, or a much higher cadence. It's supposed to take you to your absolute limit - or it's not efficient training. Like I always squat until I can't do another one, do intervals until I can't hold the power. That's the idea. The high cadence drill isn't obvious strength training, but it does take muscle to jerk our legs around like that, following a specific circle and those muscles have to fire in a very specific sequence. The faster we jerk them around, the more force has to be applied to achieve the desired leg acceleration. That's where it starts to become strength training, at a much higher cadence than one could use on the road or the track, and then holding it to exhaustion. I start with a cadence I can only hold for 15' and over a period of months, that length of time increases. The reason for very low power is to keep HR down enough that it doesn't become an issue that might cause the cadence to slow. Though I have to admit, I take September off and then when I start over in October, I'm in HR zone 3 to start with, but that'll gradually come down. Thus only muscular exhaustion slows cadence and then we quit. Just like power intervals, no sense in continuing if you can't hold the power. Similarly, doing squats we use many times the max force we would apply to the pedals. Strength training only works if we do it outside the envelope of our usual activities.

Your coach probably wouldn't let you do this stuff anyway, but I thought I'd do a better job of explaining for some future reader.
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Old 01-25-24, 09:33 PM
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I must say, I very much appreciate the criticism above. I'm defending a dissertation. There's no substance to that without very probing questions. It sharpens the mind and improves one's thought processes.
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Old 01-26-24, 05:13 AM
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Originally Posted by Carbonfiberboy

The high cadence drill isn't obvious strength training, but it does take muscle to jerk our legs around like that, following a specific circle and those muscles have to fire in a very specific sequence. The faster we jerk them around, the more force has to be applied to achieve the desired leg acceleration. That's where it starts to become strength training, at a much higher cadence than one could use on the road or the track, and then holding it to exhaustion. I start with a cadence I can only hold for 15' and over a period of months, that length of time increases. The reason for very low power is to keep HR down enough that it doesn't become an issue that might cause the cadence to slow.
When we do very high cadence drills at very low power, it takes a lot of muscular effort just to suppress the pedal force applied on the downstroke. We are basically working directly against our own leg mass and inertia to keep the pedal force low enough to avoid bouncing in the saddle. The hard work involved in achieving this is exactly what the paper I cited earlier concludes that we shouldn’t attempt to do within our normal pedal stroke. While it reduces mechanically inefficient radial force at the end of the downstroke, it comes at the expense of using additional muscle force to oppose it.

In your high cadence drill it would actually require less muscular effort if you increased the crank resistance just enough to balance your leg mass and inertia on the downstroke and power would increase effectively for free (actually better than free as it would require less muscle recruitment) - even though it would look less mechanically efficient in terms of radial forces.

The fact that you can barely walk after spinning a very high cadence at very low power, minimising “wasteful” radial pedal forces is actually a great demonstration of why it is not a good idea in a normal pedal stroke!
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Old 01-26-24, 08:06 AM
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Not sure how, or if, this pertains to the topic at hand:

As far back as 1965, when I was the only guy with a track bike on training rides with the local team/club, I learned that the only way I could keep up on long, steep downhills was to concentrate on pedaling in (what felt like) a kind of shuttling motion - straight forward, straight back. "Pedaling circles" - not a chance. It was quite a cadence drill: somewhere around 210 to 220 rpm at the highest speeds.

Other than that (if that counts), I've never done anything that could be even remotely classified as specific pedaling training. Despite that, or maybe because of that, I was always fast and strong; genetics plus riding a track bike everywhere, maybe. (Even back in the mid-1960's, one of the guys in the New Haven club was envious to the point of trying to get me thrown out of the club because he had an afternoon job and thus couldn't do as much riding as I could - it was "unfair" that, at 15, I was two years younger and yet stronger than he was.) (If you're reading this, Ken - no hard feelings.)

Don't know if I could do a cadence of 200-plus now; the last time I rode that way was probably 15 years ago. On that ride, when we stopped at the next rendezvous point, one of the riders told me that he'd started out on the descent next to me but then moved away, because "it looked as if your legs were going to tear away from your hips!"

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Old 01-26-24, 09:01 AM
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Originally Posted by Trakhak
Not sure how, or if, this pertains to the topic at hand:

As far back as 1965, when I was the only guy with a track bike on training rides with the local team/club, I learned that the only way I could keep up on long, steep downhills was to concentrate on pedaling in (what felt like) a kind of shuttling motion - straight forward, straight back. "Pedaling circles" - not a chance. It was quite a cadence drill: somewhere around 210 to 220 rpm at the highest speeds.

Other than that (if that counts), I've never done anything that could be even remotely classified as specific pedaling training. Despite - or maybe because - of that, I was always fast and strong; genetics plus riding a track bike everywhere, maybe. (Even back in the mid-1960's, one of the guys in the New Haven club was envious to the point of trying to get me thrown out of the club because he had an afternoon job and thus couldn't do as much riding as I could - it was "unfair" that I was stronger than he was.) (If you're reading this, Ken - no hard feelings.)

Don't know if I could do a cadence of 200-plus now; the last time I rode that way was probably 15 years ago. On that ride, when we stopped at the next rendezvous point, one of the riders told me that he'd started out on the descent next to me but then moved away, because "it looked as if your legs were going to tear away from your hips!"
That's good to hear, good for you! Yes, I'm familiar with that shuttle foot motion you describe, that is other fixed riders on here have mentioned it as the only way to try to keep up during descents. Were you here when The Octopus was? I do a bit of that when I do FastPedal, definitely part of the puzzle. I did my first good FastPedal in a long, long time day before yesterday and sure enough, my quads are a little sore today, probably that pushing forward thing, slightly different motion. Hams didn't notice it. That drill is about precise muscle control, as much a ganglia drill as a leg drill. So many studies of pedal motion and varying advice on that sort of thing is because of the considerable time it takes to teach our muscles to fire in a certain way at a certain time. Ganglia rule. Most folks aren't going to do anything they don't have to do and in studies, they can't do it well. In your case, you had to do it.

Never ridden fixed myself, just SS, not the same thing. We used to have a 2 who'd come out with us in the winter, fixed, so I got to watch him descend steep grades - we'd wait at the bottom. We'd pull at about 25 on the flat, so his legs would have had it after 30 miles and he'd take a shortcut back. Local legend, not the Strava kind. Wasn't any Strava back then.
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Old 01-26-24, 10:06 AM
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Originally Posted by Carbonfiberboy
I don't know why you think strength work is not material. The FastPedal drills can take more time than most strength workouts, but If I'm holding a cadence which is as fast as I can spin at low load, when I get off the bike I can hardly walk even though it was just HR zone 2. [...] Depending on the drill, either a lot more resistance, or a much higher cadence. It's supposed to take you to your absolute limit [...] The high cadence drill isn't obvious strength training, but it does take muscle to jerk our legs around like that, following a specific circle and those muscles have to fire in a very specific sequence. The faster we jerk them around, the more force has to be applied to achieve the desired leg acceleration.
Originally Posted by PeteHski
When we do very high cadence drills at very low power, it takes a lot of muscular effort just to suppress the pedal force applied on the downstroke. We are basically working directly against our own leg mass and inertia to keep the pedal force low enough to avoid bouncing in the saddle. The hard work involved in achieving this is exactly what the paper I cited earlier concludes that we shouldn’t attempt to do within our normal pedal stroke. While it reduces mechanically inefficient radial force at the end of the downstroke, it comes at the expense of using additional muscle force to oppose it.
I've often thought that high force zero speed training (e.g., 1RM strength training) has about as much theoretical basis for improving submaximal power as high cadence zero force training, but lots more people recommend the former than the latter.
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Old 01-26-24, 11:46 AM
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Originally Posted by PeteHski
When we do very high cadence drills at very low power, it takes a lot of muscular effort just to suppress the pedal force applied on the downstroke. We are basically working directly against our own leg mass and inertia to keep the pedal force low enough to avoid bouncing in the saddle. The hard work involved in achieving this is exactly what the paper I cited earlier concludes that we shouldn’t attempt to do within our normal pedal stroke. While it reduces mechanically inefficient radial force at the end of the downstroke, it comes at the expense of using additional muscle force to oppose it.

In your high cadence drill it would actually require less muscular effort if you increased the crank resistance just enough to balance your leg mass and inertia on the downstroke and power would increase effectively for free (actually better than free as it would require less muscle recruitment) - even though it would look less mechanically efficient in terms of radial forces.

The fact that you can barely walk after spinning a very high cadence at very low power, minimising “wasteful” radial pedal forces is actually a great demonstration of why it is not a good idea in a normal pedal stroke!
Really! I can tell when I have a really good gym workout because I can barely walk downstairs when I head for my car. Guess I better stop working so hard, too many reps, too much weight! The only fitness work that really matters is work done outside one's normal envelope of activity. That's why runners run, people go to the gym, etc., etc.

If I increase pedal resistance, it hides the irregularity in the pedal stroke, the very thing I am trying to eliminate. The idea of smooth pedaling is to try to maintain the same velocity all the way around. Any lost velocity has to be made up by an acceleration, and that's wasted energy. It's also helpful if both legs do the same thing, one leg not dragging the other along. That's the reason I try to never have a slack chain instant during my low load pedaling. Remember the old Mobil Gas economy runs? The object of the game was, if possible, to never use the brake or alter one's pressure on the accelerator. Efficiency. I just posted about this on that Winter Hill Climbing thread in Road Cycling.
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Old 01-26-24, 12:06 PM
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Originally Posted by Carbonfiberboy
The idea of smooth pedaling is to try to maintain the same velocity all the way around. Any lost velocity has to be made up by an acceleration, and that's wasted energy.
Acceleration, deceleration. That sounds like conserved energy.

The only wasted energy in pedaling would be effort that does not help turn the cranks.
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Old 01-26-24, 12:13 PM
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Originally Posted by RChung
I've often thought that high force zero speed training (e.g., 1RM strength training) has about as much theoretical basis for improving submaximal power as high cadence zero force training, but lots more people recommend the former than the latter.
In a data-free environment, one hundred flowers bloom.
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Old 01-26-24, 12:25 PM
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Originally Posted by Carbonfiberboy
Really! I can tell when I have a really good gym workout because I can barely walk downstairs when I head for my car. Guess I better stop working so hard, too many reps, too much weight! The only fitness work that really matters is work done outside one's normal envelope of activity. That's why runners run, people go to the gym, etc., etc.

If I increase pedal resistance, it hides the irregularity in the pedal stroke, the very thing I am trying to eliminate. The idea of smooth pedaling is to try to maintain the same velocity all the way around. Any lost velocity has to be made up by an acceleration, and that's wasted energy. It's also helpful if both legs do the same thing, one leg not dragging the other along. That's the reason I try to never have a slack chain instant during my low load pedaling. Remember the old Mobil Gas economy runs? The object of the game was, if possible, to never use the brake or alter one's pressure on the accelerator. Efficiency. I just posted about this on that Winter Hill Climbing thread in Road Cycling.
I think you misunderstood my point. Regardless of whether or not the physical effort of spinning 120 rpm at very low power makes you stronger in some way, it certainly doesn't make any sense in producing power on a bicycle. By definition, you are generating very little power with maximal effort.

This idea of a smooth, constant pedal velocity sounds intuitive, but actually involves a lot of physical effort (which actually reduces your power) as demonstrated by your low power cadence drill. So why not just press down on the pedals and stop fighting against your leg momentum in an effort to pedal more smoothly? Even unweighting on the upstroke takes a lot of physical effort, although at least that contributes a little to the net torque. We see that pro cyclists tend to do this a little more effectively. But let's not forget that pro cyclists just mash their pedals harder and don't worry much about style marks or mechanical efficiency!
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Old 01-26-24, 12:36 PM
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Originally Posted by MoAlpha
In a data-free environment, one hundred flowers bloom.
Yeah, my only data is time-on-course. But I think that's rather the point.
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Old 01-26-24, 12:39 PM
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Originally Posted by terrymorse
Acceleration, deceleration. That sounds like conserved energy.

The only wasted energy in pedaling would be effort that does not help turn the cranks.
For example, effort used to counter your leg momentum toward the bottom of your downstroke. Effectively adding a braking force.
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Old 01-26-24, 01:09 PM
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Originally Posted by PeteHski
For example, effort used to counter your leg momentum toward the bottom of your downstroke. Effectively adding a braking force.
Have you seen anything to confirm that happens? I don't think it does when riding normally.

If riders did actually push down at the bottom of the pedal stroke, they would bounce in the saddle at high rpm. AFAIK, bouncing in the saddle is still a no-no. That pesky Third Law. Back when I would go out with geared bikes on a SS, I'd have to hold 135 for long periods in the paceline, no bouncing. At my g.i. that's ~24 mph IIRC.

So the question remains, did I pull up to decelerate those legs, or did I allow the pedal to do it for me? Of course the pedal did it, so that shows as downforce on a plot because the pedal is pushing up against my foot, slowing it. But by the bottom, that downforce (actually an up-force from the pedal) has succeeded in stopping my foot's downward motion. Note, I did not push down, rather the pedal pushed up or seen another way, the fast motion of my leg on the downstroke created momentum in that leg, and I used that momentum to push the pedal down, rather than having a muscle do it and waste energy. I don't see why that doesn't occur to people. The pedal can't tell whether it's muscle force or momentum that's pushing on it.

Of course that doesn't create as much power as pushing down with muscle force all the way, so that's how we sprint and how most riders ride a TT. However it's more efficient to let the pedal slow your leg, which is what counts on an endurance ride.
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Old 01-26-24, 01:29 PM
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Originally Posted by terrymorse
Acceleration, deceleration. That sounds like conserved energy.

The only wasted energy in pedaling would be effort that does not help turn the cranks.
That last: Exactly so. But no. All acceleration burns more calories than steady-state. Hence my referral to the Mobil Gas economy run on one of these threads. The most efficient pedal stroke keeps a constant speed throughout the pedal stroke.

You would be correct if there were a way to save that conserved energy and feed it back into the system, less losses incurred during said saving, just like a modern electric car coasting or going downhill. But our bodies don't have a way of storing that energy. Entropy, the heat death of the universe and all that. When we spend it, it's gone.

The bike does store energy though most folks understand that varying the bike's speed on a climb wastes energy. That used to be a big argument for light wheels, but it turns out that top riders keep a very steady pace and no energy loss has been detected in tests between very light and very, very heavy wheels other than that from the weight itself. Of course light wheels save energy on a climb but only in that they contribute to the total weight of the bike. I can't remember where I saw the study. November? Now they all climb with deep rim wheels, still light, but not as light as they could be. Aero's even more important at low speeds because they can save energy over more time. So they say. Remember Helium rims? I only saw those for 1 or 2 seasons, then just gone.
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Old 01-26-24, 03:43 PM
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Originally Posted by Carbonfiberboy
That last: Exactly so. But no. All acceleration burns more calories than steady-state. Hence my referral to the Mobil Gas economy run on one of these threads. The most efficient pedal stroke keeps a constant speed throughout the pedal stroke.

You would be correct if there were a way to save that conserved energy and feed it back into the system, less losses incurred during said saving, just like a modern electric car coasting or going downhill. But our bodies don't have a way of storing that energy. Entropy, the heat death of the universe and all that. When we spend it, it's gone.

The bike does store energy though most folks understand that varying the bike's speed on a climb wastes energy. That used to be a big argument for light wheels, but it turns out that top riders keep a very steady pace and no energy loss has been detected in tests between very light and very, very heavy wheels other than that from the weight itself. Of course light wheels save energy on a climb but only in that they contribute to the total weight of the bike. I can't remember where I saw the study. November? Now they all climb with deep rim wheels, still light, but not as light as they could be. Aero's even more important at low speeds because they can save energy over more time. So they say. Remember Helium rims? I only saw those for 1 or 2 seasons, then just gone.
This calls for some clarification:

Yes, acceleration requires more energy than maintaining a steady speed, but the cost of that acceleration is gained back by the decreased cost during deceleration.

There is a way to save the energy put into acceleration and feed it back. It's called kinetic energy. If you happen to be accelerating uphill, there's another type of stored energy: potential energy.

No, varying the speed on a climb does not waste energy. Unless you look at the secondary effects, like rolling resistance and wind drag. But for most climbing situations, you are simply converting pedaling energy into potential energy.

Pros climb with somewhat deep rim wheels, but not as deep as they use on faster stages. Pros climb fast, so reducing aero drag is more significant to them than saving a few grams. Not true for most of us less talented climbers, for whom weight is the most important thing.
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Old 01-26-24, 04:18 PM
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Originally Posted by terrymorse
This calls for some clarification:

Yes, acceleration requires more energy than maintaining a steady speed, but the cost of that acceleration is gained back by the decreased cost during deceleration.

There is a way to save the energy put into acceleration and feed it back. It's called kinetic energy. If you happen to be accelerating uphill, there's another type of stored energy: potential energy.

No, varying the speed on a climb does not waste energy. Unless you look at the secondary effects, like rolling resistance and wind drag. But for most climbing situations, you are simply converting pedaling energy into potential energy.

Pros climb with somewhat deep rim wheels, but not as deep as they use on faster stages. Pros climb fast, so reducing aero drag is more significant to them than saving a few grams. Not true for most of us less talented climbers, for whom weight is the most important thing.
Sorry, that's simply incorrect. Look it up for cars like:
https://nepis.epa.gov/Exe/ZyNET.exe/...kPage=x&ZyPURL

We burn fat and carbs, cars burn gas or Diesel, it's the same thing, but we only have numbers for cars. It's just physics.
Pros actually climb very smoothly. Again, look it up. That's the reason the wheel weight didn't make a difference other than as being a part of the bike.
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Old 01-26-24, 05:27 PM
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Originally Posted by Carbonfiberboy
Sorry, that's simply incorrect. Look it up for cars like:
https://nepis.epa.gov/Exe/ZyNET.exe/...kPage=x&ZyPURL

We burn fat and carbs, cars burn gas or Diesel, it's the same thing, but we only have numbers for cars. It's just physics.
Pros actually climb very smoothly. Again, look it up. That's the reason the wheel weight didn't make a difference other than as being a part of the bike.
If you are talking about micro acceleration and deceleration within each pedal stroke then the physics tells us that it simply cancels out in terms of energy consumption. Heavier wheels actually damp out these slight speed fluctuations anyway. Not to mention that the accelerations are of tiny (insignificant) magnitude. Even a full bore sprint acceleration requires very little additional power to spin up heavier wheels. It’s very easy to calculate. I made a quick spreadsheet last time this was argued.

This is not the same thing as a rider constantly attacking on a climb and then sitting up. Of course that is inefficient in terms of our energy systems.
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Old 01-26-24, 05:45 PM
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Originally Posted by Carbonfiberboy
All acceleration burns more calories than steady-state. The most efficient pedal stroke keeps a constant speed throughout the pedal stroke.
This word “efficient” again. This constant speed pedal stroke ideology is not at all convincing given the way we physically apply pedal forces.
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