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Thread: Quad Burn

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    Quad Burn

    I've noticed over the last couple of months of training that my quads start to burn WAY before anything else, both in time and intensity. So much so that I think my FTP would be 20-30 watts higher if I had more endurance in this part of the body. The burn is in the top right portion of the quad a couple of inches up from the knee.

    Is this a bike fit thing or a quad strength (endurance?) thing? If it is a strength thing, is there anything specific I can do? I've been putting in a lot of LT work and seeing great results, but unfortunately my quads never seem to have the same failing point as the rest of my legs (calves, hamstrings, etc).

    Thanks!

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    Just anecdotal / I can't back it up with studies: When my quads start to hurt early, I find increasing carb intake as well as heavily loading up on electrolytes during the ride, potassium and magnesium vitamins during the week, etc. helps. After hard rides, I've been taking Amino Acid supplements (Amino Vital is the product I'm currently using)... Sure helps recovery-and therefore makes the quads fresher on the next ride...

    -mm

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    Legs of Steel chrisvu05's Avatar
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    buy a foam roller and start stretching. When my quads start getting imperceptibly tight they seem to burn faster. I spent Oct-May this year doing physical therapy. Part of the PT was Foam roller work every visit. When I started riding again my quads would never burn (except for intervals). Now when my quads start to burn in a ride I'll hit the foam roller that night and the quads will be good for a few weeks without stretching.

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    Quote Originally Posted by Hammonjj View Post
    but unfortunately my quads never seem to have the same failing point as the rest of my legs (calves, hamstrings, etc).

    Thanks!
    I'm confused. Why would you expect anything different. Cycling is a quad intensive exercise. Of course they see the results before your calves, or hamstrings. Yes, the other muscles are in use, but the quads and glutes are much more important in cycling.

    Hamstrings are almost totally out of the equation, as are the calves. probably 80 percent of the motive force is provided by the quads, and glutes. Hamstrings are used to bend the knee, which is certainly important in cycling, but a very small percentage in power output, and quite honestly, you can cheat and ride the pedal up, rather than getting a good rotation. In any case, a very small percentage of the total power output, even if performing a perfect pedal stroke. Calves, are pretty much along for the ride. They are in use, but in pretty much an energy free isometric mode. You want to see what a calve burn feels like, then do 300 lb calve raises. You will get the idea. You don't use them anywhere near that capacity in cycling.

    If you think that you are ever going to get a muscle to fail before the quads when cycling, you are sadly mistaken. Concern yourself with what matters. Build your quads. Push them to failure often. Strength training is not a bad thing.

    There are some good anatomy resources as they relate to training out there. They would help you to understand a little better what each muscle group does, and how they interact.

    EXRX.net is a good one.

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    50000 Guatts of power 127.0.0.1's Avatar
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    want a simple ?

    ez to try....works for me

    take 3 or 4 tums before rolling out. srsly....
    and roll your legs with massage stick before beddies
    I like fat bikes
    and I cannot lie.

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    Quote Originally Posted by chrisvu05 View Post
    buy a foam roller and start stretching. When my quads start getting imperceptibly tight they seem to burn faster. I spent Oct-May this year doing physical therapy. Part of the PT was Foam roller work every visit. When I started riding again my quads would never burn (except for intervals). Now when my quads start to burn in a ride I'll hit the foam roller that night and the quads will be good for a few weeks without stretching.
    Do you just place the roller under your quad and roll around or is it more complicated than this?

    Thanks
    James

    EDIT: Never mind, a quick youtube search yielded tons of results on how and what to do with a foal roller!
    Last edited by Hammonjj; 08-07-09 at 12:42 PM.

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    just another gosling Carbonfiberboy's Avatar
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    Quote Originally Posted by dahoyle View Post
    I'm confused. Why would you expect anything different. Cycling is a quad intensive exercise. Of course they see the results before your calves, or hamstrings. Yes, the other muscles are in use, but the quads and glutes are much more important in cycling.

    Hamstrings are almost totally out of the equation, as are the calves. probably 80 percent of the motive force is provided by the quads, and glutes. Hamstrings are used to bend the knee, which is certainly important in cycling, but a very small percentage in power output, and quite honestly, you can cheat and ride the pedal up, rather than getting a good rotation. In any case, a very small percentage of the total power output, even if performing a perfect pedal stroke. Calves, are pretty much along for the ride. They are in use, but in pretty much an energy free isometric mode. You want to see what a calve burn feels like, then do 300 lb calve raises. You will get the idea. You don't use them anywhere near that capacity in cycling.

    If you think that you are ever going to get a muscle to fail before the quads when cycling, you are sadly mistaken. Concern yourself with what matters. Build your quads. Push them to failure often. Strength training is not a bad thing.

    There are some good anatomy resources as they relate to training out there. They would help you to understand a little better what each muscle group does, and how they interact.

    EXRX.net is a good one.
    Actually, your calves and hamstrings provide a great deal of power during the stroke, along with the hip flexors. Try to pedal so that you never feel the sole of your shoe. Just put the weight of your leg on the pedal in the downstroke, then use your hamstrings, glutes, and hip flexors until you get to about 10:00. Then push forward with the quads and again let your leg fall. I'll often cramp in my hamstrings before my quads. If your quads get tired or start burning, stop using them and pedal with your hamstrings instead. When your hammies cramp, pedal with your quads. You can trade back and forth. I've never cramped a glute, FWIW.

    To improve the strength and coordination of your whole leg, find a 10-15 minute hill with a fairly smooth slope. Pedal seated in a big gear at a steady 50 cadence, HR at about 90% of LT. Most importantly, don't allow your upper body to move at all. Do it all with your legs. Keep the pedal speed very even through the whole stroke. Do repeats until your speed starts to drop off. You'll see what I'm talking about. You will feel the shoe sole at that cadence, but you shouldn't at 90 or better. You will need a computer with cadence to keep it even.

    Could partly be a bike fit thing, since it's just in that one spot.

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    Senior Member reef58's Avatar
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    What is your cadence. I find my legs tire quicker a lower cadences.

    Richard

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    I'm happy when my quads burn -- it means cardio is not my most limiting factor and my overall fitness is decent, which not the case too much of the time.

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    Quote Originally Posted by Carbonfiberboy View Post
    Actually, your calves and hamstrings provide a great deal of power during the stroke, along with the hip flexors. Try to pedal so that you never feel the sole of your shoe. Just put the weight of your leg on the pedal in the downstroke, then use your hamstrings, glutes, and hip flexors until you get to about 10:00. Then push forward with the quads and again let your leg fall. I'll often cramp in my hamstrings before my quads. If your quads get tired or start burning, stop using them and pedal with your hamstrings instead. When your hammies cramp, pedal with your quads. You can trade back and forth. I've never cramped a glute, FWIW.

    Sorry, but you are mistaken. Cycling is predominantly a Push exercise. Certainly, a proper pedal stroke involves every muscle in your leg, but the power comes from the Quads and Glutes. Anatomically, and in terms of energy produced, they are way more important. There are lots of athletes with below the knee amputations who still perform at an amazing level, for that very reason.

    Additionally, your glutes are not used in lifting your leg, as you indicate "then use your hamstrings, glutes, and hip flexors until you get to about 10:00". Your glutes are exactly the opposite of your hip flexors, so they are obviously not used in the same portion of the stroke.

    Your Hip Flexors (Pectineus) are hip adductors, while your Glutes (Gluteus Maximus) are hip abductors. So, hip flexors, lifting the pedal, glutes, pushing the pedal. Sorry if that isn't how you understand it, but it is anatomically what is happening.

    The degree that calves (Gastrocnemius & Soleus) are involved in pedaling are directly related to cleat placement (fore and aft), and the technique, but it is still a very small portion of the actual stroke, and work performed. The farther forward your cleats are, the more you use them, and the inverse is also true. The more you ankle, the more you use them. If you used full ankle range of motion (plantar and dorsaflexion) involving both the calves and tibialis anterior, it is still a miniscule energy production compared to the amount of energy provided by the Quads.

    Your hamstrings , consisting of (1. Biceps Femoris, Long Head 2. Biceps Femoris, Short Head 3. Semitendinosus 4. Semimembranosus) are rather unique, in that they are both knee flexors, and hip extenders. They are therefore involved to a degree in both the up and downstroke.

    Simply put, we have evolved over thousands of years to walk upright, and support much more than our individual weight on our legs. The muscles which lift us off the earth, for lack of a better way of describing it, have developed tremendous strength compared to the relatively smaller and weaker ones which are designed by evolution to do no more than lift an individual limb high enough to advance it the next step. While the smaller ones can be trained to perform at a higher level than normal, they can come nowhere near the power capability of the greater muscles (quads and glutes). Your calves are there primarily for ballance to enable you to walk upright. Again, they can be trained to a degree, but it is a small percentage of the total. I am sure that once you think about it, you will realize why you can not develop anywhere near the same power on the upstroke as you can the downstroke.

    I won't argue what your particular results are, just that you misinterpret which parts of the anatomy are involved, and what is happening.
    If you are pedaling anywhere near your max capacity, then you are doing way more on the downstroke than the upstroke.

    This is basic anatomy and physiology. There are many resources available to improve your knowledge on the subject.
    Last edited by dahoyle; 08-10-09 at 11:01 PM.

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    Quote Originally Posted by reef58 View Post
    What is your cadence. I find my legs tire quicker a lower cadences.

    Richard
    I feel the same way. For a given speed, the lower cadence equates to a higher gear, requiring more pressure on the pedals to do the same work, than a lower gear, at higher cadence. One could argue that the work output is the same, but there are many variables at play. you can move a small weight a set distance many times, much easier than a heavier weight the same distance, a fewer number of reps.

    A good example would be with simple weights. Most people would be able to lift 30 lbs, 2ft twenty times. Few would be able to lift 200lbs 2ft, 3 times. The work being done is the same, but the immediate demands placed on the muscle are much higher at the higher load, and it will obviously fatigue much more rapidly.

    Certainly, the same thing happens when cycling, to a greater or lessor degree, depending on individual anatomy and cadence.
    Last edited by dahoyle; 08-10-09 at 10:54 PM.

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    just another gosling Carbonfiberboy's Avatar
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    Quote Originally Posted by dahoyle View Post
    Sorry, but you are mistaken. Cycling is predominantly a Push exercise. Certainly, a proper pedal stroke involves every muscle in your leg, but the power comes from the Quads and Glutes. Anatomically, and in terms of energy produced, they are way more important. There are lots of athletes with below the knee amputations who still perform at an amazing level, for that very reason.

    Additionally, your glutes are not used in lifting your leg, as you indicate "then use your hamstrings, glutes, and hip flexors until you get to about 10:00". Your glutes are exactly the opposite of your hip flexors, so they are obviously not used in the same portion of the stroke.

    Your Hip Flexors (Pectineus) are hip adductors, while your Glutes (Gluteus Maximus) are hip abductors. So, hip flexors, lifting the pedal, glutes, pushing the pedal. Sorry if that isn't how you understand it, but it is anatomically what is happening.

    The degree that calves (Gastrocnemius & Soleus) are involved in pedaling are directly related to cleat placement (fore and aft), and the technique, but it is still a very small portion of the actual stroke, and work performed. The farther forward your cleats are, the more you use them, and the inverse is also true. The more you ankle, the more you use them. If you used full ankle range of motion (plantar and dorsaflexion) involving both the calves and tibialis anterior, it is still a miniscule energy production compared to the amount of energy provided by the Quads.

    Your hamstrings , consisting of (1. Biceps Femoris, Long Head 2. Biceps Femoris, Short Head 3. Semitendinosus 4. Semimembranosus) are rather unique, in that they are both knee flexors, and hip extenders. They are therefore involved to a degree in both the up and downstroke.

    Simply put, we have evolved over thousands of years to walk upright, and support much more than our individual weight on our legs. The muscles which lift us off the earth, for lack of a better way of describing it, have developed tremendous strength compared to the relatively smaller and weaker ones which are designed by evolution to do no more than lift an individual limb high enough to advance it the next step. While the smaller ones can be trained to perform at a higher level than normal, they can come nowhere near the power capability of the greater muscles (quads and glutes). Your calves are there primarily for ballance to enable you to walk upright. Again, they can be trained to a degree, but it is a small percentage of the total. I am sure that once you think about it, you will realize why you can not develop anywhere near the same power on the upstroke as you can the downstroke.

    I won't argue what your particular results are, just that you misinterpret which parts of the anatomy are involved, and what is happening.
    If you are pedaling anywhere near your max capacity, then you are doing way more on the downstroke than the upstroke.

    This is basic anatomy and physiology. There are many resources available to improve your knowledge on the subject.
    This is an interesting discussion. We didn't really evolve to walk - we evolved to run. That was our "leg up," if you'll permit me. Running makes use of many of the same muscles we now use for cycling. In fact runners often have more developed hamstrings than do cyclists.

    If I wish to demonstrate the power developed by the backstroke while out of the saddle, I can lift the entire bike off the ground with a powerful unbalanced backstroke and easily lift the rear wheel with a moderate unbalanced backstroke. It's necessary to pedal circles, or at least balance downstroke and backstroke while sprinting out of the saddle to wring maximum power from the legs while keeping traction on the rear wheel. This is especially true when sprinting uphill, as one must move body weight far enough forward to avoid lifting the front wheel and losing steering, and yet have it far enough back to avoid losing traction.

    I only experience cycling as a Push exercise when resting out of the saddle on a long climb. I do ride with one person who primarily pushes at a low cadence. He bobs his shoulders very noticeably and is a relatively fast long distance rider, so it's not unknown. If I try to pick up the pace and start pushing, the complaints from my quads always remind me to involve the rest of my legs. Hence my answer to the OP.

    To bolster my intuitive argument, we can watch the pros. They do not normally bob their shoulders nor pry on the bars when riding in the saddle. If the vast majority of the work were done on the downstroke, it would be necessary to do those things to resist that downward thrust. We can see a video model of the cycling muscles in action here:
    http://www.youtube.com/watch?v=Fb6oNTkqxSc&NR=1

    We can see very nice visuals of the muscles involved in pedaling here:
    http://cozybeehive.blogspot.com/2006...-to-pedal.html

    On the Beehive web page linked above, Stephen Thordarson's experimental data shows glute activity centered around 45. I seem to have trained my pedal stroke to center glute activity around 0, perhaps to introduce a little more power into that part of the stroke. The only really difficult part of the stroke is at about 310, when the hams are almost fully contracted, so perhaps that's why I've done that. Also notice how much muscle activity takes place all the way around the stroke.

    Climbing performance is limited by VO2 and energy production adaptations, not by muscular strength. Endurance at any speed is increased by increasing the volume and thus the number of muscles involved in the stroke. The more we can spread out the load, the faster we can climb. Watch Lance and see how he relaxes his foot and pulls up on his heel cup when climbing out of the saddle. Otherwise, pros use their muscles much the same whether sitting or standing. Similarly when sprinting, the more muscles we can involve in the stroke, the more power we can produce.

    I urge the reader to practice pedaling circles when climbing seated and to practice a powerful backstroke when sprinting. These techniques are great levelers.

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    Dahoyle's two posts seem correct to me and are in line with what I've read about anatomy and exercise studies. I have difficulty understanding what Carbonfiberboy is trying to say.

    Quote Originally Posted by Carbonfiberboy View Post
    If I wish to demonstrate the power developed by the backstroke while out of the saddle, I can lift the entire bike off the ground with a powerful unbalanced backstroke
    But can you do this with platform pedals too?

    My reason for bringing this up is that the same issue rears its head in discussions about platform-vs-clipless. Some folks argue that clipless pedals are better than platform pedals because they allow the rider to pull the pedal up, and so to exert power during a longer phase of the pedal revolution. If these folks were right, there would indeed be significant use of hamstring+hipflexor in cycling.

    However, research has shown that this is not the case. During normal riding, cyclists do not pull up on the upstroke (or backstroke if you want to call it that), instead they try to make sure that the downward force is as small as possible. This way they make sure that the one leg is not working against the other leg.

    In fact, exercise physiologist often recommend that cyclists do hamstring exercises off the bike, because the imbalance created by strong quads & weaker hamstrings can lead to knee problems.

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    just another gosling Carbonfiberboy's Avatar
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    Quote Originally Posted by dizzy101 View Post
    Dahoyle's two posts seem correct to me and are in line with what I've read about anatomy and exercise studies. I have difficulty understanding what Carbonfiberboy is trying to say.



    But can you do this with platform pedals too?

    My reason for bringing this up is that the same issue rears its head in discussions about platform-vs-clipless. Some folks argue that clipless pedals are better than platform pedals because they allow the rider to pull the pedal up, and so to exert power during a longer phase of the pedal revolution. If these folks were right, there would indeed be significant use of hamstring+hipflexor in cycling.

    However, research has shown that this is not the case. During normal riding, cyclists do not pull up on the upstroke (or backstroke if you want to call it that), instead they try to make sure that the downward force is as small as possible. This way they make sure that the one leg is not working against the other leg.

    In fact, exercise physiologist often recommend that cyclists do hamstring exercises off the bike, because the imbalance created by strong quads & weaker hamstrings can lead to knee problems.
    You don't understand what I'm saying because you haven't trained to ride efficiently. Sorry.

    Trials riders can lift the bike with platform pedals, though I don't quite see how. Yet another discipline! I haven't ridden platforms for 50 years. But they're not lifting the bike the way I'm saying, in a sprint.

    You need to watch more pros ride. You might also try doing a lot of one-legged pedaling on rollers or get a set of Powercranks. All these things will improve your riding. OLP is the single most important climbing exercise I do, muscle tension intervals being next on the list. Of course actual climbing is good, too, but IME the drills add a lot, expecially in early season, like February - April.

    Getting more hamstring power is actually more difficult to do off the bike than on, because the range of motion in cycling is so particular. IMO knee curls are worthless. Good Mornings are good, as are straight-legged deadlifts - my favorite. You work up to sets of 30 fast SLDLs at 135 and you'll have some powerful hams. But be careful and work up slowly over a couple of years: it's easy to injure yourself.

    What I'm saying is that you may be right: most riders may not use their hams or hip flexors much. But if you start pedaling the way I'm talking about, you'll be a faster climber with much more endurance at high output, and your quads won't burn on a long climb like the OPs.

    You'll also sprint with much greater acceleration. It's a joke in my riding group: I'm 64 y.o. with little talent, a crappy VO2max, ordinary legs, and a BMI of 25, yet only two people will contest sprints with me any more, and they are very seriously talented people who climb about 1.5 times as fast as I, and are 20 years younger. Yes, I pull up hard on the backstroke when sprinting, very hard, using the heel cup on my Sidis. The anterior tibialis isn't strong enough to resist the pull of strong hams. Completely impossible to do with platforms. There is no argument over whether platforms or clipless are more efficient, only over whether it's reasonable to trade the loss of efficiency for walkability. Racers went to toe clips as soon as they were invented in the late 19th century:
    http://www.examiner.com/x-532-Denver...cling-Examiner
    Back in the day, I filed slots in the bottoms of my shoes, or just let the pedal wear make them, rather than attach a cleat to the shoe bottom. Toe clips were a revelation. I was sure that if I could only pedal a little harder, I could pop a wheelie. I may have been right.

    When climbing seated I normally pull up only on very steep hills or when accelerating in an attack. When riding single-speed, I pull up on all hills over about 4%. However, my hams always do a lot of work at the bottom of the stroke and the beginning of the backstroke. Also, the stronger your hip flexors and hams are, the more you can unweight that back leg. Fully unweighting it is not a trivial use of muscle power.

    Do try those one-legged pedaling intervals on rollers. I'm up to about 5 minute intervals.

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    I'll keep this short. You're incorrect. During normal riding, pros don't pull on the upstroke. Check out this post (click link) for some references to books on the exercise science of cycling. This has been thoroughly researched. (However, occasionally while climbing at low cadences cyclists DO pull--but this is pretty rare and doesn't hugely affect efficiency.)

    I don't deny that one-legged cycling exercises on a bike can be useful. It can improve the efficiency of one's pedal stroke. I also agree with you that clipless is better than platform. But that does not mean it's because it allows one to pull upward.

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    just another gosling Carbonfiberboy's Avatar
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    I think you're repeating my last paragraph with different words. Please re-read. I think we agree on most points, though I still argue that Lance and some others definitely do pull up on the backstroke when climbing out of the saddle at full power. See this video:
    http://www.youtube.com/watch?v=sjY0zm8_qo0
    When Lance and Pantani are accelerating out of the saddle, their foot motion sometimes changes on the backstroke, indicating that they are pulling up. In fact, notice how similar their pedaling motion is, frequently rather different from the pedalling of the other racers. After I saw Lance doing that in 1999, I started trying to sprint that way with positive results, and urged others to try it. Some of my riding buddies have done so, also with positive results, particularly on hill sprints.

    But this discussion got jerked into an argument over whether riders pull up on the backstroke, which is unfortunate. Rather than argue about whether or not most cyclists normally pull up on the upstroke, in which dizzy is correct, I'm would like invite the reader to think about how they can unload their quads during the pedal stroke by using more of the muscles in their legs. The drills we believe are useful help a great deal with that. I believe that ideally, both sides of the leg should cramp at the same time if we do too much anaerobic climbing for our conditioning level. We can extend the mud-scraping action at the bottom maybe to 230 with practice, and start the kick-the-dog action at the top maybe 30 before TDC with practice, as we see Lance and Pantani doing.

    BTW, the van den Bogert article is no longer available at the link you give. I found it some time ago at:
    http://74.125.155.132/search?q=cache...&ct=clnk&gl=us

    I hadn't seen the Gregor and Conconi before. They have this paragraph on p.31:
    "Tests with US national team riders in the road, track and mountain bike disciplines reveal that kilometre track specialists and mountain bike racers have the lowest relative oscillations in total power during pedalling. Kilometre specialists must reduce oscillations because average power is well in excess of 1000 W, and thus they must distribute power to the pedal over more of the cycle to avoid extremely high peak powers. Low oscillations in mountain bike racer pedalling mechanics appear to be highly functional as rear wheel traction on loose soil depends in part on continuous and smooth power flow from the pedals."

    It's my belief that reducing the power output oscillations in the pedal stroke adds efficiency for two reasons. 1) It spreads the load out among more muscles, reducing the stress on each. 2) It reduces the accelerations in each pedal stroke which the graphs in the Gregor and Conconi show often occur. These accelerations waste power. The old saws "pedal circles," "heels down and pedal round," and "dig with your heels" are old saws because they work.

    The video linked above also demonstrates other interesting pedalling features. Lance and Pantani pedal the downstroke with the bottom of the foot mostly horizontal, i.e. they don't "ankle," in fact the reverse. To the rider, this feels like the heel is down because of the pronounced bend in the ankle. A hair after BDC the ankle is flexed and the toe goes down, while the toe begins the push-back at the bottom of the stroke. For some biomechanical reason that I don't fully understand, this adds power to this point in the stroke, more than I think would result from the ankle flexion alone. Then immediately after, the back and upward pull continues for another maybe 45, even on pedal strokes when they do not pull up on the remainder of the backstroke. The heel is up on the whole backstroke and all the way over TDC, higher when they pull up, lower when they do not. The heel does not come down until immediately after TDC. I believe the heel is up on the backstroke because that decreases the stress on the anterior tibialis and because it moves the heel forward where the upper leg muscles can act on it more effectively.

    And as sadly mistaken as I am, I sometimes do cramp a ham before a quad.

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    Senior Member Garfield Cat's Avatar
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    Even after I installed the Rotor Rings, I still use the pull up but it feels shortened in length due to the oval rings.

    I think its Alberto Contador who is known for acceleration during climbs. Even if he is being attacked during a climb, he can accelerate off the saddle.

  18. #18
    just another gosling Carbonfiberboy's Avatar
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    OK. I haven't been out on the bike in a week. Been too busy playing and doing other things. Went out this evening on our tandem. Paid very close attention to my pedalling. It varies a lot with wattage. At a normal cruise, maybe 200w, 21-22mph, I only feel the sole of the shoe from 90 to 180. I start pushing forward at about 330, and continue that to about 50. I don't seem to do anything from 50 to 90 except let my leg fall. I start pulling back at about 170 and continue pulling back and up to about 230. My heel rises only slightly on the backstroke.

    Thinking about those angles, it's obvious that I mostly pedal with one leg at a time, that I spread out the load between muscles, and that I apply an near constant torque to the bottom bracket. When I'm using the hamstrings, I'm not using the quads much on the other side. I use the quads for the part of the pedal stroke that's blank on the backstroke. Only at TDC and BDC do I use both legs at the same time when doing easy. Going harder, I use both legs at the same time through more of the pedal stroke. One hears that when riding rollers. Just a steady humm is what you want. None of this rrRRrrRRrrRR.

    If I kick the wattage up to an estimated 300w, I feel weight in my shoe from about 60 to 180 and pull back and up all the way to 270. My heel is noticeably higher on the backstroke. I tried to pick it up to 400w or so, but my tandem position isn't the same as on my single and I couldn't get the pedalling to work the same - my legs felt cramped on the backstroke if I really pulled and let my heel come all the way up. In any case, I never pull up seated after about 310. It's not efficient.

    However, it was obvious to me that testing for force vectors at 250w, as was done in those references, doesn't tell us much, except that's how people ride when they're loafing. If we pick up the wattage to 450 like Lance, our pedaling is definitely going to change. There's absolutely no need to pick up that heel on the backstroke at low wattages - there's so little force. It's the applied force that raises the heel. However, if we're going to extract the maximum available power from our bodies, we need to pedal every inch of that stroke. Their raised heels speak to the force required to reach those wattages. Very impressive.

    All the preceding seated, of course. Standing, stoker and I have enough trouble riding in a straight line, much less getting fancy with the pedaling. On the tandem we only push when standing. As I said before, on my single I only pull up standing while sprinting. I don't have the aerobic capacity to do it steady-state while climbing.

    So it turns out that seated I do always pull up on the backstroke. Dwell angle of the pull increases with wattage, as does force all around the circle. Comes from years of chasing down riders 20 years younger in the fast group. I had to keep getting more efficient as I aged, so I learned how to pedal, among other things.

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