PeteHski

Well all I can say is that a lot of contemporary studies disagree with you about trying to reduce radial forces. It sounds intuitive, but that’s a trap that we often fall into with cycling history.

The studies you linked to earlier are interesting, but don’t actually contradict any of the studies I mentioned. They focus on guided pedal force feedback in an attempt to increase IFE, but they don’t really address the elephant in the room that is whether or not reducing IFE in this way is actually beneficial to cycling performance.

Have you ever considered investing in a pair of power meter pedals so that you can analyse your own pedal stroke? It would be interesting to see how far removed you are from the standard force vector model that you are saying is “totally wrong”.

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.

PeteHski

Ha, ha. That’s why I decided to become an engineer. We make science into reality

MoAlpha

It's essentially a library where you can upload .pdfs of anything you want, which is not in itself a problem, but according to the journal publishers it's theft. There are all sorts of bottom feeding journals indexed in MEDLINE too and available on PubMed, and being indexed there implies no quality control or endorsement by the National Library of Medicine or the US Govt, so it's always caveat emptor.

As for research being free, yes it should be. Currently, all NIH-funded research must be made freely available within a year of publication and there is a new mandate that it be freely available immediately. I hope other governments and NGOs will follow suit. However, the solution is to pay a reasonable open-access fee to a reputable journal, which handles the editorial and peer review process and deserves compensation for it, not to take copyrighted material and post it on a dodgy site.

MoAlpha

I'd also suggest that cycling is a problem of energy metabolism, not mechanical efficiency. The two are related but not coextensive and once the basic pattern is established, the nervous system is going to refine the neuromuscular program to minimize energy demand by shifting activity to muscles and parts of muscles that are efficient for non-mechanical reasons such as blood supply, glycogen content, and mitochondrial density.

PeteHski

I think this is why studies chasing mechanical efficiency ie minimising radial forces and maximising tangential forces, never appear to prove any clear performance advantage in doing so.

For example those pesky, non-propulsive, radial forces near the bottom of the pedal stroke are certainly detrimental to the calculation of mechanical efficiency. But the muscle activation in eliminating them would be a bit like stopping your golf or tennis swing from following through naturally after striking the ball.

I think that’s why all pro cyclists simply mash down on their pedals and let their feet naturally follow through without trying to artificially reduce or even reverse their pedal force toward the bottom. Their muscles would actually be fighting against both gravity and inertia to achieve that goal and that’s why we don’t see it happen in force vector plots with significant power and cadence, regardless of how much “foot scraping” or “pedalling circles” is perceived.

The pros obviously mash down harder than we do, but the force vector plots still look much the same and nothing remotely like the perfect mechanically efficient solution.

ZHVelo

Don't those journals rake in cash but don't pay peer reviewers much? And really, what makes science science is the peer review process, otherwise it's just someone writing whatever. If researchers would benevolently peer review each other's work (as many do anyway already as peer reviewers of journals) with the idea "I peer review this piece and someone else will peer review mine", the journal and its ridiculous fees can be jumped over.

But of course many don't want to, because the prestige of certain journals is how they rank each other, and those with connections certainly wouldn't want it and so on and on.

MoAlpha

Yes, the big publishers, Elsevier, Springer, Wiley, et al., make huge profits and get lots of free labor. Ad hoc reviewers are almost never paid and neither are part time editors. I put in several hours a week as a section editor on two Elsevier journals for nothing but the honor of the thing and my employer lets me do it as official duty because that’s what guys like me are supposed to do.

Here’s a peek into the workings. The vast majority of reviews are ad hoc, meaning the editorial office gets a submission and sends to an editor like me. If I decide it’s good enough after a quick read, I find peer reviewers for it and send it out I may know a few people who are right for a particular paper, but it usually involves a bit of online searching, particularly to find the young researchers who have the time and motivation to do it. Often, I have to send it to 10 or 15 people to get 2 or 3 good reviews. Then, when the reviews come in, I have to decide whether to send the paper back to the authors for revision, often more than once, or reject it. I have excellent admin support from my editorial offices, which are housed at the academic institutions where the Editors in Chief work, also often for nothing. Support staff are paid either by the organization who “own” the journal, such as a scientific or clinical society, or the publisher.

Journals are ranked on commercial metrics of how often articles in them are cited by other articles. The most commonly used metric is something called “Impact Factor.” There is no source of prestige other than that, but since high impact journals attract more and better submissions and those, in turn, attract more attention and get cited more, the rich tend to get richer. There are also thousands of junk journals publishing garbage and profiting from the prevalent “open access” model, where the author pays for publication and the publication is free to the public.

The model is outmoded and gradually failing. Pretty soon, I think government mandates on access will force some kind of reorganization. Funding organizations like the NIH have enough purchasing power to demand concessions on publication fees and squeeze the big publishers. It can’t happen too soon..

Carbonfiberboy 

I was going to write a post supporting the use of tangential forces for efficiency, as possibly supported by this study::
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3628359/
But then I realized, who cares? Very few, if any riders who visit this forum have goal rides exceeding 200k or involving multiple 1 hour pass climbs, which is where greater efficiency starts to make a real difference. If one doesn't bounce at cadences over 120, one is already limiting radial force. There was that Newton guy.

MoAlpha

This is an interesting study which was designed to investigate the rather old theory that the motor system is organized to activate muscles in particular groupings and timings or “modules” and the fresher question of whether these modules are selectively recruited according to feedback condition. They used two conditions, a “just pedal” one, where the feedback was purely internal, and one where participants were instructed to produce maximally tangential force. They called this “Effective Pedaling” presumably because it is mechanically optimal and I don’t think anyone would dispute that. However, the study had nothing to say about what was or is biomechanically or bioenergetically most efficient, and for experimental purposes, the feedback could have been aimed at producing any kind of pedal stroke.

terrymorse 

200km rides with multiple long climbs? Yes, please. Not now, but later in the year.

Great, now all I can think about are long rides with multiple big climbs. Markleeville, Mammoth Lakes, Bishop, Mt Lemmon, Colorado front range. Road trips!

ZHVelo

My goal for the year actually

PeteHski

Exactly. If we pedal many thousands of miles over many years our pedal stroke is likely to become optimised automatically. At least if we pay attention to our bike fit. Steve Hogg makes a similar point in this blog post.

https://www.stevehoggbikefitting.com...-what-is-best/

Steve Hogg quote from above link:-

“It [pedalling technique] is within your conscious control on flat roads at 25 km/h if you choose it to be, because the load is light and there’s plenty of time to ‘play’ with pedaling technique if you choose to. But who cares?

Riding at slow speed and light load has it’s place, but when the pressure is on and the wattage rises, don’t worry about your pedaling technique. Accept what comes naturally to you and refine it by doing it (riding) a lot. What results is the best technique for you, for who you are functionally and for the position (good, bad or indifferent) that you have on your bike.”

Trakhak

Great quote from Steve Hogg; thanks. The sentence I highlighted reminded me of the time that, during a race, I overheard a teammate complimenting a guy on another team for his smooth pedaling technique. When I asked him after the race what that was about, he said, "I could tell from how still his upper body was that he was concentrating on keeping his pedaling smooth. I figured, as long as he's wasting energy, why not try to get him to waste a little more?"

There are some older posters here who seem to believe sincerely that pedaling as smoothly as possible, a.k.a., "pedaling circles," is unmixedly beneficial. Even back in the 1980's, my teammate knew otherwise. One old guy (who quit posting in a snit a few months ago) insisted that these days all riders pedal at too low a cadence, what with their newfangled 10- and 11-tooth sprockets, while he serenely ignored the 30-tooth sprocket on the other end of their cassettes.

How I see this topic: our quads and glutes are much bigger than our hamstrings because evolution favored swift runners. Running entails an application of explosive force followed by a comparatively lengthy low-effort follow-through---hence our smaller hamstrings. No point in dragging around extra meat.

So I try to replicate that distribution of force while cycling: a brief burst of effort across the front followed by as long a recovery period as possible in the rest of the circle.

That, by the way, is why rollers are fine for zone 1 or maybe 2 efforts---where the smoothness that rollers require doesn't interfere with efforts to produce higher power, or at least not much---but are inferior to stationary trainers for anything else.

The people who ran the Colorado Springs U.S. Olympic Training Center evidently reasoned the same way, because their roomful of rollers was replaced with stationary wind-resistance trainers the year that those hit the market. I replaced my rollers with a Racer-Mate trainer pretty quickly back then, too.

Edit in anticipation of arguments from roller fanciers:

Yes, rollers can be equipped with fans and the like to add resistance. Sure, but stationary trainers, and especially smart trainers, are much easier to use for doing intervals. You concentrate on the workload without the distraction of having to balance and steer.

And no, rollers don't make you a better pack rider. Anyone who can ride 50 feet without falling over has all the balancing skill necessary to ride in a peloton. Steering a bike safely in a peloton is a matter of judgment, not balance.

Carbonfiberboy 

Yeah, that's the sort of thing where I did the best. I've finally gotten my heart thing sorted and I'm back at it but with a CTL of 25. It's gonna be a long road. '25 maybe.

This thread reminds of of when I joined here, back in '07. By then I'd been doing bike-specific strength training for about 10 years and found that it worked really well, giving me a killer sprint and better endurance on long rides. But I was the only poster here who thought that. Back then, everyone else here agreed that all strength training did was steal time away from cycling and make riders put on unnecessary weight. This kinda feels just like that and we still see some residue from that here. I've been training my pedal stroke since '95, haven't had to think about how I was pedaling in decades. That said, I do pedal stroke maintenance every year. Even skiing, every year I work on the same things, I never "just ski." That's how one gets good at doing a thing. Cement it into one's ganglia and constantly reinforce that information.

Just watch Shiffrin run slalom. She's changed the sport. Go back and watch slalom videos from a decade ago: and now: Besides incredible talent, a lot of that's training and specific strength training. Watch the slo-mo and see how she brings her skis off the snow coming out of those turns. That's how hard she's pushing down in the turn (and Vilhova is starting to do that too), the g-forces she's generating to get her though the turn more quickly.

Anyway, back to cycling. Every year, I do these drills:
1) From October to January 1 I do FastPedal on my rollers. Until I hit 70, I'd try to pedal in a very small gear on my rollers at 115-120 rpm for 15'-45', once a week, gradually increasing the time while trying to stay in HR Z2. In the fall I'd be slower and a lot of Z3, but I'd get better as the weeks went by. The trick is to relax the feet, wiggle the toes, keep the feet flat, and pedal with the uppers, trying to keep a little air between one's socks and the shoe's insole.

2) From January 1 to April 1, I'd change that once a week to one-legged pedaling, again on my rollers, 2' right leg, 2' left leg, 2' legs together in Z2, alternating the cadence in the one-legged sets between 55 and 85 rpm, freely chosen cadence for legs together. Then repeating that sequence until I start to get a slack chain on the backstroke or 45', whichever comes first. Most people find that this is not easy. Early on in the season, I cut the 2' interval short if I get that slack chain, which I define as failure, but keep on trying until I just can't. I figure if I'm not crying for my mommy, I can keep at it. When I could do 2' consistently, I'd increase the gear so it was still at my limit, and of course I'd use a different gear for the 55 and 85 cadence sets.

3) For 4 weeks in April, I change that once a week to 50-55 cadence Z3 X 10' hill repeats, no upper body movement. By then, this felt quite natural.

The nice thing about this work is that until the end of March, this is all of relatively low aerobic impact. It works your legs but not your aerobic/hormonal system. So even though it's hard to do, the impact on training load is low, but the performance impact is large..

Of course I don't pull up on the backstroke when riding normally, but I do unweight that pedal to reduce downforce in the downstroke. The object of this whole thing is to reduce radial forces in the pedal stroke. Any energy one spends on radial force is endurance lost. I'm actually a mediocre physical specimen who got into it late and taught himself to keep up with the faster folk 10 or so years younger on long rides. Strength training also helped a lot as did just riding my butt off.

This is now late January. If one was inclined, one could shorten this up and do a month of each exercise in the progression. This probably won't be enough time to really cement this into one's ganglia, but enough time to see what happens as one goes through the phases.

Carbonfiberboy 

See my response to ZHVelo.

PeteHski

Sigh.....no point in wasting any more time on this then.

Trakhak

Anecdata always wins.

Carbonfiberboy 

That's familiar. Though by simple inspection it should be obvious that force which does not propel the bike is wasted force, whether or not it may be useful under some circumstances. There is this study, where we see that pros do pedal differently than non-pros, especially at higher power levels, no great surprise, and that much of this difference is in pulling up during the start of the backstroke, i.e. engaging the hamstrings or rectus femoris as well as unweighting the backstroke pedal the rest of the way up and then pushing forward at the top. Which is exactly what I'm advocating.
https://journals.plos.org/plosone/ar...l.pone.0282391
as well as these:
https://pubmed.ncbi.nlm.nih.gov/36928839/
https://pubmed.ncbi.nlm.nih.gov/21507064/.

In any case, we are doing science when we experiment.

PeteHski

I am just going to refer you back to posts #21 & 22 again regarding the restriction of radial forces and the consequences of doing so.

FWIW I do cadence drills too because I want to maximise my useful cadence range. The difference is that I just concentrate on hitting the cadence targets and don’t try to over-think my technique. I have also done single leg drills, but I gave up on those after I came to the view that they are probably a waste of time, unless you find them fun, which I don’t. Or if you are one-legged of course! I didn’t lose any performance after I stopped doing them. Otherwise I would have started doing them again.

Hermes

I do not do cadence drills or pedaling drills - not on my prescription. My take is that when one practices something to improve or get to the next level there must be materiality. Okay, doing one leg pedaling drills for an hour - that is material. Two minutes seems too short. The same is true for cadence drills. Go on the track and ride a 40 minute warmup in a smaller gear with fast guys. That will spin one up and if one can complete the workout be material.

For new riders, sure, pedaling drills, cadence drills and etc make sense. For advanced riders - meh.

Carbonfiberboy 

Thanks. I have no disagreement with what you see in that first link. Of course that's what one does in a sprint. But sprinting is interesting to me. I wound up with a very good hill sprint, maybe only 85 rpm. My ordinary pedaling style had so increased the power of my hamstrings that I had to be very careful of my weight distribution. Too far forward and I'd lift the rear wheel, losing traction. Too far aft and I'd lift the front wheel, losing steering. I was by far the fastest hill sprinter among my riding group until I got old and a younger guy beat me. I was also one of the fastest on the flat. Of course part of that is from strength training, but being able to pull up that hard in a sprint was partially because I always pull up on the first maybe 55° of the backstroke, though with less effort at the top of at angle. 90° on the downstroke is where one develops the most force. It's not that hard to put an equivalent torque on the BB using both pedals at the top and bottom of the pedal stroke. When seated, two legs combined can put out that max force..

About pedal stroke analysis - many analysts forget that there are 2 cranks. One wants to fill in the light spots on one side with force on the other so that ideally (IME) there's little variation in the torque being applied to the BB. That's most of the purpose of the drills I posted above. And I wonder what the max downstroke force usually is at say 300w and 90 cadence? I'm sure that's been measured but can't find it.

I haven't been able to do a successful FastPedal in about a year and a half (heart). I got on my rollers this evening for the first go at it in a long time. Wow, was that tough (and rough). I was only spinning 100 at about 80 watts, so very low load, and I kept having instances of chain slack, mostly on the backstroke, IOW that foot wasn't keeping up with the other foot or maybe I was accelerating that foot too fast at the bottom of the backstroke, and at only 100 rpm. After about 15 minutes, that unevenness went away. As Kafka said, "There is hope, only not for us."

The Fuji climb was also interesting. He was climbing at 2375'/hr. That's a good rate for the average club rider, but not an example of superior performance on a relatively short ride. When I was 72, I was climbing 1900'/hr for the last 1000' toward the last high point (Sunrise, Mt. Rainier) of a 55 mile, 6000' day and I've always been a slow climber. I was probably about an hour behind the faster guys, only in their 60s.

AFAIK the record in a long race was set by the doping Il Pirata on the Giro, ~6000'/hr. If you noticed in that PLOS 2023 study, modern pros, when going hard, pull up with their hamstrings at the bottom of the backstroke, about like I do, and then unweight that pedal for the rest of the way up, not pulling up, just unweighting so the downstroke pedal doesn't have to lift that weight. Because my max force is pretty low, I do that all the time. Keeps my quads alive. If they cramp, I can pedal just fine with my hamstrings and if they cramp, I just go back to my quads. If they both cramp, I have to stop and drink pickle juice. It helps that I do one set of leg lifts on the Roman chair to exhaustion twice a week, but then there are many things which are helpful.

PeteHski

That’s a bold claim and highly unlikely. Do you have any examples of such an obvious oversight?

PeteHski

I agree. Out of pure coincidence I ended up doing a cadence ramp workout yesterday (which I haven't done in years). Basically just half a dozen cadence ramps from 100-130 rpm with a few minutes recovery in between. The first ramp I did was a little lumpy, but the rest easy enough. Power was set at around 250W in ERG mode. As you say - meh.

I do more low cadence work because of all the steep climbing I need to prepare for. But I get that just from virtual climbing on Zwift with my Wahoo bike simulating my road bike gearing. Steep ramps drop my cadence down into the 50s or less at FTP and I find that translates well into real life climbing, along with strength training off the bike.

Carbonfiberboy 

Wow! You can pedal continuously with one leg on the trainer for an hour? I bow, your ARE incredible.

I also think that if it doesn't tire me out, it's not worth doing. It is way easier on the road because the crank inertial load is much higher. On my old ABS drum rollers, that load's almost zero. I purposely choose a gear which limits me to an absolute max of 2' for the OLP before I start getting a momentary slack chain. I use a much larger gear for the 50-55 cadence than the 80-85. I'm trying to mimic strength training in the gym, where ~30 reps to exhaustion takes me between two and three minutes, depending on the exercise. Even advanced riders benefit from strength training.

For the FastPedal, I do it until either I can't do it perfectly anymore (no chain slack) or 45', whichever comes first. For me, pedaling near 120 in a low gear for a long period does tire my legs out, but really once I can to it for 45' what I'm getting is reinforcement for my ganglia. My challenge, other than the time, is keeping it in HR zone 2, which would mean that I've become adequately efficient. I've tried not doing these drills for a year and found that my climbing suffered. That's because I try to do one of those drills once a week for about 28 weeks.

A decade or two ago, when I went out with our moderate group for the Sunday ride, I'd drop to the back of the pack and do the climbs one-legged, or I'd ride in the group and drop my cadence into the fifties. Either way I'd get to combine a moderate aerobic workout with a tiring strength and pedaling workout. These drills are all designed to fall outside the normal pedaling envelope, which is why I do them. Working my legs harder than I'll ever have to on a usual road endurance ride is a good thing and the whole point.

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.

Anyway, that's the reason I posted this pedaling stuff on a strength thread, because the way I do it, it's strength training. As I say, if it's not hard, I wouldn't be doing it.