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  1. #1
    'Mizer Cats are INSANE Mentor58's Avatar
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    Determine Most Efficient Cadence???

    Hey Gang,

    I've searched, but come up empty, so here's my question. Is there any fairly simple way to determine the most efficent cadence for an individual. For example, my natural-feeling cadence on flats, no wind seems to be around 110 or so, but some folks that I ride with tell me that I'd be better at 90-100 RPM, that high of cadence is more stressfull on the cardio system.

    I'm wondering if I could do something on the trainer with my HRM to try and determine at what cadence my system is working best overall. Problem is that I don't think that just a straight graph of "RPM vs Heartrate" will solve anything. I'm thinking that due to the various factors (resistance, gearing, speed, etc) that the measurement I'd be looking for would be something like "heartbeats per mile". Yea, I've got too much time on my hands.

    What limited thought processes I have make me think that this would indicate portion of the envelope that everything is working most efficently at. Please let me hear your feedback on this, I know that it's very possibly solving a problem that doesn't exist, but isn't that the purpose of having a hobby?

    TIA

    Steve W.
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    There have been many studies of most efficient cadence (you can search PubMed or Google) and the results always show a most efficient cadence around 60 rpm. The problem is efficiency (power produced per unit of power available from O2 or fuel consumed) is not a good metric for cycling. The object in racing is to cover the distance faster than the competition (mass start) or in the least possible time (TT's). Any other measure (efficiency, heart rate, etc) is meaningless and efficiency doesn't factor significantly in winning races. Outside of competition, there could be other objectives, but I wouldn't put efficiency on the list.

  3. #3
    a blend of wit and charm Moochers_Dad's Avatar
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    It's 88 rpm. trust me.

  4. #4
    more ape than man timmhaan's Avatar
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    possibly the best idea is to ride a certain course at different ranges of cadence and see what the best times are. pez cycling (i think?) did an article on that. turns out the guy was faster overall with a lower cadence.

    of course, this would just be a snap shot of your current abilities. most beginners have a slower cadence than more experienced cyclists, but that's not always the case. i guess what i'm trying to say is that your natural cadence can change over time.

  5. #5
    'Mizer Cats are INSANE Mentor58's Avatar
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    Quote Originally Posted by asgelle
    There have been many studies of most efficient cadence (you can search PubMed or Google) and the results always show a most efficient cadence around 60 rpm. The problem is efficiency (power produced per unit of power available from O2 or fuel consumed) is not a good metric for cycling. The object in racing is to cover the distance faster than the competition (mass start) or in the least possible time (TT's). Any other measure (efficiency, heart rate, etc) is meaningless and efficiency doesn't factor significantly in winning races. Outside of competition, there could be other objectives, but I wouldn't put efficiency on the list.

    Look at it from the point of view of a touring rider who is interested in getting into Brevet riding. In this case Time isn't the primary concern, it's making the most efficient use of the limited amount of energy that the rider has available to cover long distances within a set time. Think if it as more a MPG competition than a MPH race. Seems like there ought to be a semi-rational way of determining at what pace ones own body is working most effectively, in terms of distance covered vs energy used.

    I'm getting back on the bike after about 4 weeks off due to an auto accident (cracked ribs, bruised sternum, hard to ride when you can only breathe at about 50%) , so right now it's hard for me to make any accurate judgements. I did make a concerted effort to keep my cadence down in the 90=100 range, as opposed to my usual 105-115 with spells at 120 range. I noticed that I seemed to have more power and felt good after the ride, but it was a short one (20 miles or so), really just designed to get my back out and riding, not really a test of anything.

    I'm thinking that the basic test would look like this... ride a fixed speed on the trainer (that will help eliminate variables like wind and road conditions), using different gearing to get various cadences between 80 and 110 or so. Spend enough time in each gear so that the heart rate can stabilize. Record and try next cadence set. I would think that the most efficient cadenc would be the one that resulted in the lowest heart rate. Going back to my example, that would be the highest MPG. For fun I'll toss in a run at 60 RPM, even if I know that my knees would file a restraining order against me if I tried that on an all day ride.

    Steve W
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    Quote Originally Posted by Mentor58
    Look at it from the point of view of a touring rider who is interested in getting into Brevet riding. In this case Time isn't the primary concern, it's making the most efficient use of the limited amount of energy that the rider has available to cover long distances within a set time.
    See my first post. There have been plenty of studies on cadence and efficiency. You should be able to search for them as well as I. As to your proposal, why do think minimum heart rate occurs at maximum efficiency?

  7. #7
    Long Distance Cyclist Machka's Avatar
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    In one of my books, it talks about ideal cadences for different types of cycling ... just a moment ... let me see if I've got that book within arm's reach .... OK, I don't seem to have that one right here, however, what it said basically was this:

    New cyclists generally ride with a cadence of <70 rpm
    Endurance cyclists (and possibly also Time Trialists) ride with a cadence of somewhere between about 85 and 95 rpm
    Racers ride with a cadence of >100 rmp.

    Another book I have here (Bicycle Medicine) also indicates that the optimum cadence for endurance is fairly low (in the 80-85 rpm range).

    As it happens my cadence is 85 rpm ... and that seems just about right for me!


    BTW - I thought you'd vanished from the forums for a bit there ... I hope you are healing well.

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    Quote Originally Posted by Machka
    In one of my books, it talks about ideal cadences for different types of cycling ...
    I thought the question was about most efficient cadence. That's not the same as ideal or optimum.

  9. #9
    Long Distance Cyclist Machka's Avatar
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    Quote Originally Posted by asgelle
    I thought the question was about most efficient cadence. That's not the same as ideal or optimum.
    In my language "ideal" and "optimum" would equal (or at the very least include) "efficient". If you are cycling at the ideal and optimum cadence for your type of event, wouldn't that also mean that it would be efficient?

    But if it is efficiency in particular that you're after, have a read over pages 111 to 118 in Bicycling Medicine by Arnie Baker. He says a lot of things in those pages, but in particular he says this: "almost all studies have shown that the most efficient cadence is still well below 80 r.p.m." ... and then a page later, he summarizes the section by saying, "Each rider's optimal cadence is specific to that rider. No matter what the studies say, you've got to find your own."

  10. #10
    'Mizer Cats are INSANE Mentor58's Avatar
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    Hi Machka.... Yea, between being unable to ride for a while, and some extra consulting work that I took on I've not posted anything much lately. IIRC the local Borders Books has a copy of that, and since it's right next to my usual haunt for Sunday Breakfast, I may just look at it.

    I may have been guilty of not being as precise in my language as possible. What I'm looking at is finding a cadence that will maximize my endurance and still allow for effective cycling. Having done some touring and a few (for me) long distance rides, (300 miles in 3 days), I feel that my usual high cadence may be working against me. Based on some of the studies that I've seen on the web, a high cadence tends to be more cardio-vascular stressful than lower (which makes sense), and also utilizes a larger percentage of Fast Twitch Muscles. A lower cadence will tend to utilize Slow Twitch Muscles, and would be better for maximizing performance if your metric is "riding long distances with speed being of secondary concern".

    I know my knees and suspect that going sub 80 on the cadence for any length of time will not make them happy. On the other hand, constantly spinning like a hampster on crack may not be the best option for me either. I think I'll spend some time working at moving the cadence down into the 90's and see how that feels. I know that one century I did this summer I tried that and found that I had a lot more in my legs toward the end of the day.

    Steve W.
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  11. #11
    Senior Member Richard Cranium's Avatar
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    What limited thought processes I have .......... Please let me hear your feedback on this, I know that it's very possibly solving a problem that doesn't exist..........
    Yes, had you given your post a little thought, you would have realized that "optimal cadence" can only be expressed in relation to "optimal load." And yes, selecting optimal load is a very important problem for most cyclists.

    Whenever you downshift by selecting an easier gear, during a bicycle ride, you are actually doing something more important than adjusting you cadence - you are adjusting your load. [pedal resistance]

    Whenever you upshift by selecting an harder gear during a bicycle ride, you are actually doing something more important than adjusting your cadence - you are adjusting your load. [pedal resistance]

    So, had you given your post a little thought, you would have asked this question:How do I determine the optimal cadence [pedal frequency] for riding my bicycle at a constant speed for this specific length of time. [specific distance] I would expect a cyclist could include a "steady-state" constant-grade hill-climbing-problem also, but ther answers would be too variable because of the nature of rider power-to-weight ratios.....

    OK, so someone go tell this guy what his optimal cadence is for some selected speed on flat, windless pavement. But remember to tell him what he is really doing -is selecting his optimal load.
    Last edited by Richard Cranium; 10-22-06 at 09:18 AM.

  12. #12
    Senior Member DannoXYZ's Avatar
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    Cadence is a matter of balancing your muscles vs. your cardiovascular system. At any given speed, there's a required amount of power that you have to generate to overcome aero and rolling-resistance. How you generate that power is up to you, but it's given by the following:

    POWER = PedalForce X RPM

    At any given power-output, you can push hard at low-RPM or push lightly at high-RPM.

    Then in order to balance the muscles vs. lungs, you determine which one is the limiting step in your riding. If your muscles get tired, sore and cramped up first, then you'll want to spin higher-RPMs with lower force (lower gears) to preserve your muscles.

    If your lungs & heart are falling out and your legs don't feel a thing, then use higher gears and push the pedals harder.

    Quote Originally Posted by Mentor58
    I may have been guilty of not being as precise in my language as possible. What I'm looking at is finding a cadence that will maximize my endurance and still allow for effective cycling. Having done some touring and a few (for me) long distance rides, (300 miles in 3 days), I feel that my usual high cadence may be working against me. Based on some of the studies that I've seen on the web, a high cadence tends to be more cardio-vascular stressful than lower (which makes sense), and also utilizes a larger percentage of Fast Twitch Muscles. A lower cadence will tend to utilize Slow Twitch Muscles, and would be better for maximizing performance if your metric is "riding long distances with speed being of secondary concern".
    I think you're mixing up two different concepts, cardio vs. muscular balance (determined by RPM) and fast vs. slow-twitched as determined my muscle-force. We've gone over cadence above.

    the percentage ratio of force generated from fast vs. slow-twitch muscles is determined by total force. Your muscles can only generate up to a certain amount of max-force, as determined by a 1-rep max-lift. At this load level, you're using 100% of both your fast & slow-twitch muscles with the primary contribution coming from fast-twitch anaerobic muscles.

    At the lower load-levels, say a 40-50 rep lift, you'd use primarily aerobic slow-twitch muscles.

    On the bike, there's actually a 3d graph of muscle-load X RPM X fast/slow-twitch depending upon the power-required. The higher the power-generated, the more pedal-force requried and more utilization of fast-twitch muscles. HOWEVER, at any given power, you'll still use more slow-twitch muscles at higher-RPMs due to the lighter loads on your muscles. For example, take the following two power-outputs and the required pedal-force

    200-watts output ~19mph
    90 rpms = 27 lbs average force on pedals
    60 rpms = 39 lbs average force on pedals

    400-watts output ~25mph
    90 rpms = 53 lbs on pedals
    60 rpms = 80 lbs on pedals

    You'll see that the lower-cadence at any given power-output will require higher force at the pedals. Depending upon where your LT is, a function of max-lift strenght and aerobic efficiency, you'll use a ratio of fast vs. slow-twitch muscles. But as you get closer and closer to LT with higher pedal forces, you'll get a larger and larger portion of force from the fast-twitch muscles.

    There is yet another variable (resulting in 4D graph) of fat vs. carb utilization which affects endurance on long rides. Fast-twitch, high-force muscles use primarily carbs for energy while slow-twitch, low-force muscles use a lot of fat. Pushing hard on teh pedals in high-gear will have you burn up carbs at a faster rate than pushing ligher in low-gears which would burn up a higher percentage of fats. If your endurance-limit is partly determined by energy-supply & bonking, this will play a role as well.


    So to find your "optimum" cadence... compare the end-results you have now and see how varying your cadence will affect it. Is your "endurance limit" a muscular-fatigue issue? Like your muscles are sore, cramped and tired? Then a higher-cadence would actually reduce muscle-loads and increase your endurance. If your lungs and heart tire out first and your legs feel fine after a double-century, then you might to push harder on the pedals and use a higher-gear.
    Last edited by DannoXYZ; 10-22-06 at 12:28 PM.

  13. #13
    Oil it! sfrider's Avatar
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    This is one of those things people buy power meters for... You can go crazy otherwise speculating over what impact 1-2mm of seat height, crank length, road surface, saddle fore/aft position, arm positions, etc, all have on power production. Each one is very minor, and is only meaningful if part of addressing everything as a system. For instance, you may need to change hand and seat positioning to really take advantage of a cadence change.

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    Quote Originally Posted by sfrider
    This is one of those things people buy power meters for...
    Some quotes from Andy Coggan on the use of powermeters for positioning.
    http://forum.slowtwitch.com/gforum.c...t_reply;so=ASC

    "Looks can be deceiving: it's really nothing but a highly-adjustable, eddy-current braked, ergometer, the likes of which have been around since before 1900. They're almost indispensable when doing laboratory-based research, but almost worthless when it comes to optimizing someone's position on a bike."

    and this

    In Reply To
    >>Very true. Fit is an ongoing thing, but as this fit bike was explained to me, it shows power output as you are riding and you can tweak your position while riding (via remote control and motors controlling seat height, bar height, etc). Thus, you can see if a 3mm raise in saddle height yields more power or less power, or you can see the change in power with a lower or higher saddle to bar drop, etc.<<

    "And how, pray tell, do you control your relative effort, so that you know that any changes in power output aren't simply due to you choosing to work harder/less hard in any position? The answer is that, short of making a maximal effort, you can't...and even if you have the time and are willing to repeatedly torture yourself on multiple occasions (to eliminate fatigue effects), you still haven't accounted for adaptation/accomodation. "

  15. #15
    Faster but still slow slowandsteady's Avatar
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    In my language "ideal" and "optimum" would equal (or at the very least include) "efficient". If you are cycling at the ideal and optimum cadence for your type of event, wouldn't that also mean that it would be efficient?
    Well not necessarily. It depends on what you are doing. Let's take an extreme example of a 100m sprint(running). What is ideal for that type of race is all out speed with no regard for efficiency. There is nothing efficient with running like you are being chased by a lion. But, that will get you to the finish line faster than any other method.

    A higher cadence may be more effective for long events because once glycogen stores are gone from muscles you are done. The heart however, has the ability to get its nourishment from the entire body. Generally speaking, the heart doesn't tire out. If it did, we would die.

    Your leg muscles however, can cause you to collapse if you push them hard enough. You get that burny jello feeling. That is why people talk about having a higher cadence since less effort is done with your legs which have a lower threshold for work than your heart does. The key to finding the perfect cadence has to do with your fitness level and that is based on the individual. The more in shape you are cardio wise, the higher the cadence you can tolerate and the more you can save your legs.
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    There is no definitive answer to what a good cycling cadence is. Right now it is actually diffucult to decide whether you should train to optimize for a slower or a faster cadence. I have commented on a study in this article about pedalling frequency.

    In the study 9 trained cyclists completed two rides with 180W for 2˝hrs - one with freely chosen pedalling rate and one with a fixed pedal rate, which was around 20 revolutions lower. Following 2˝hrs riding, they did a 5 min all-out test. In this test the "slow cadence" made the highest VO2 peaks and felt better during the ride. I think that this study is quite interesting, since so many people argue for extremely high cadences.

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    figuring the cadence

    How do I figure what my cadence or rpm is?

  18. #18
    Senior Member DannoXYZ's Avatar
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    Quote Originally Posted by asgelle
    In Reply To
    >>Very true. Fit is an ongoing thing, but as this fit bike was explained to me, it shows power output as you are riding and you can tweak your position while riding (via remote control and motors controlling seat height, bar height, etc). Thus, you can see if a 3mm raise in saddle height yields more power or less power, or you can see the change in power with a lower or higher saddle to bar drop, etc.<<

    "And how, pray tell, do you control your relative effort, so that you know that any changes in power output aren't simply due to you choosing to work harder/less hard in any position? The answer is that, short of making a maximal effort, you can't...and even if you have the time and are willing to repeatedly torture yourself on multiple occasions (to eliminate fatigue effects), you still haven't accounted for adaptation/accomodation. "
    Exactly! You need to have some controls that are held constant in order to determine what changed. With three variables you're monitoring, POWER, BIKE-POSITION, and... O2-CONSUMPTION? you need to hold one constant, change the 2nd and see how it affects the third. Even then, the "efficient" measurement-metric will vary depending upon the event:

    1. SPRINTS - would require a bike-position, pedaling-form and gearing that gives you maximum power-output. In this case, "efficient" is measured in "shear power-output".

    2. TIME-TRIALS covering point A->B in the shortest amount of time can be judged "efficient" in terms of "fastest average speed". You'd want to balance gearing such that your HR and VO2-max coincides roughly with your muscle's LT. Spin too low a gear and your HR will be over VO2-max, and tax your heart & lungs while your legs take it easy. Spin too big a gear and your HR will be below VO2-max; your heart & lungs aren't working at maximum, yet your legs are over the edge. Balancing the two will give you the highest average-speed.

    3. ENDURANCE may be measured with the "efficiency" test of "calories/burned per ride"? or maybe "average-speed"? Or whatever, I have no idea what people mean when they say "improve endurance". Is it completing a double-century without having sore & cramping legs? Or is it finishing a double in under 10-hours? Without a concrete quantifiable measurement of what constitutes "efficiency" in regards to endurance, it's really impossible to figure out how to improve it.


    BTW - the measurement of "power-generated per Oxygen-consumed" is pretty worthless really. That typically comes out "most efficient" to operating your muscle at 60-rpms or so. The most efficient athlete ever tested at the OTC was a football linebacker. He generated the most power for O2-consumed ever tested. But he certainly couldn't keep up with the rest of us on the rides due to his size (blocks a lot of wind) and his weight caused him to literally come to a standstill as soon as we hit a hill.

    While you may be able to generate X-watts @ 60rpms and Y-oxygen consumed, this Y amount is typically only a percentage of your VO2-max. You may actually be able to generate 2X-watts by using 3Y-oxygen. Not as "efficient", but you'll go faster. A better metric of cyclists efficiency may be "wattage@VO2-max" perhaps. In which case, you'll find that higher-RPMs will allow you to generate maximum-wattage at VO2-max without throwing your muscles well over their LT limit. You're really comparing a cartesian product, 2x2=4, of oxygen-consumption versus lactate-threshold. There's plotting a 3D graph which may show maximum power-output with taking both variables to their limits.

    As slowandsteady mentioned, it's darn hard to recover from pushing your muscles over LT and having them be sore & tired; you'll have to stop and rest, perhaps even end the ride prematurely. Recovering from pushing over VO2-max on the other hand, can be as easy as shifting gears...
    Last edited by DannoXYZ; 10-24-06 at 09:14 PM.

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    Senior Member howsteepisit's Avatar
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    What is "effective"? I see it a lot in this thread, but to me effective means making the bike roll down the road/path whatever. Efficient, thats different. Sorry, one of my moments about ineffective language
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    why can't HR be a (relatively) accurate indicator of effort?

    I was thinkng about this yesterday during a low intensity ride...

    I can hold:

    160bpm and 260 watts at 85 rpm
    or:
    160bpm and 220 watts at 100 rpm

    of course i could just pedal a bit harder at 100 rpm and bring the power back up, but then my HR would increase, so if i were wanting to go faster, shouldn't I just pedal harder and increase the HR at 85rpm?

    So can someone please explain why 85rpm wouldn't be my ideal cadence period, and that anyone with access to a powertap couldn't do the same for themselves?

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    Senior Member DannoXYZ's Avatar
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    Quote Originally Posted by brianappleby
    why can't HR be a (relatively) accurate indicator of effort?

    I was thinkng about this yesterday during a low intensity ride...

    I can hold:

    160bpm and 260 watts at 85 rpm
    or:
    160bpm and 220 watts at 100 rpm

    of course i could just pedal a bit harder at 100 rpm and bring the power back up, but then my HR would increase, so if i were wanting to go faster, shouldn't I just pedal harder and increase the HR at 85rpm?

    So can someone please explain why 85rpm wouldn't be my ideal cadence period, and that anyone with access to a powertap couldn't do the same for themselves?
    That's because HR is only measuring your heart/lungs. There's also your muscles, which has a different indicator. It's like comparing the tachometer vs. the speedometer in a car.

    The "ideal" cadence comes down to your personal physique and power-output. In general the higher the power-output needed, the higher the RPM. Try putting out 400w for a while at two difference cadences and note how your legs feel as well.

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    Quote Originally Posted by DannoXYZ
    BTW - the measurement of "power-generated per Oxygen-consumed" is pretty worthless really. ...

    A better metric of cyclists efficiency may be "wattage@VO2-max" perhaps. ...
    Except "efficiency" has already been defined as it is first used above. The second usage is just a misapplication of the word. If people want to talk about the cadence that gives the best desired outcome (however that's defined) they can do so, but the word "efficiency" can't be used in that context.

  23. #23
    Now Racer Ex Vinokurtov's Avatar
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    Your optimum cadence is pretty easy to determine if you have a power meter or access to a Computrainer, either of which has downloadable data.

    Do a 30-60 minute TT effort sitting just below your LT, or percieved max sustainable exertion level. Ride 10 minute intervals keeping a target cadence.

    Download the data and you can plot cadence over watts. More watts is indicitive of your most effecient cadence. Factor in a bit of a drop over time.

    Any other measure is mumbo jumbo.

    Case in point: During this year's District TT championships I got to ride with an SRM for the first time. The downloaded data confirmed what I was seeing on the meter. Drop below 88 rpm and my watts dropped off. 88-95 and I produced my best numbers.

    Keep in mind that high cadnece effeciency requires adaptation, which will take quite a few months of training. That's been my experience and so says Dr. Evil (aka Michele Ferrari).

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    Senior Member DannoXYZ's Avatar
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    Quote Originally Posted by asgelle
    Except "efficiency" has already been defined as it is first used above. The second usage is just a misapplication of the word. If people want to talk about the cadence that gives the best desired outcome (however that's defined) they can do so, but the word "efficiency" can't be used in that context.
    Ok, if we go by the OP's use of the word, then yes, your post on 60rpms is about right for that definition as it goes give the most power for O2-consumed. However, I think the context of the OP's post is more about "effectiveness" maybe? Somehow improve his endurance rides, but I'm not sure what that improvement would be. How would he know he improved it? If you do a century or double-century at 60rpms, you're gonna feel sore, cramped & wiped out just halfway through...

    Quote Originally Posted by Vinokurtov
    Case in point: During this year's District TT championships I got to ride with an SRM for the first time. The downloaded data confirmed what I was seeing on the meter. Drop below 88 rpm and my watts dropped off. 88-95 and I produced my best numbers.

    Keep in mind that high cadnece effeciency requires adaptation, which will take quite a few months of training. That's been my experience and so says Dr. Evil (aka Michele Ferrari).
    Yeah, you've got years of practice and experience to balance your muscles & aerobic system. Beginners probably don't have the form or conditionining to extract the most from their body like you.

    So the measurement-metric should perhaps be "wattage/O2-consumed@LT" then? Without a gas-analyizer to do real-time measurement of blood-gases, it's hard to determine actual pedal-force that throws you over LT, but you can approximate by feel pretty good. It's typcially when the burn starts. Then do several runs in different gears and different RPMs all at the same "burn" sensation. Measure output wattage & O2-consumed. You'll notice that O2-consumed at the highest-wattage output is not as "efficient" as at lower-RPMs and lower-wattage outputs. But you're still going faster.
    Last edited by DannoXYZ; 10-25-06 at 07:28 PM.

  25. #25
    Senior Member Richard Cranium's Avatar
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    Yeah, finding an optimal cadence is a "dynamic" process, my point is that more often than not optimum cadence is a reflection of acceleration or slowing due to increasing or decreasing loads.

    All the previous comments are theoretical bull manure. Should you be doing laps on a fixed gear at an indoor velodrome, you can go on with your BS.......

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