davetapson Posted December 17, 2008 Share Right, the common wisdom is:1. Pedal fast - it's easier.and:2. Fast pedalling uses slow twitch fibres.3. Slow pedalling uses fast twitch fibres. The logic used to figure this out is:1. to go a certain speed, you need to output a certain power (measured by watts.) So let's say we want to go x kmh which will take y watts.2. You calculate power as force on the pedal x cadence you're pedalling at i.e. power = force x cadence. Can't argue with that. However, the argument then goes:1. to get y watts of power, you can either pedal slowly with lots of force, or fast with little force. Can't argue with that, either. THEN you get: Slow pedalling (low cadence) takes fast twitch muscle fibre and fast pedalling (high cadence) takes slow twitch muscle fibre... Can someone explain to me how a FAST action (e.g. high cadence) utilises SLOW twitch muscle fibres...!!?!?? I'm telling you boet, someone hasn't thought this through properly.... If you ask me, slow pedalling takes slow twitch fibres and fast pedalling takes fast twitch fibres. Anyone got any proper scientific info that says different? Link to comment Share on other sites More sharing options...
THE BODY CENTRE Posted December 17, 2008 Share The slower cadence resulted in fewer, but more forceful contractions required to maintain the constant speed. It may sound counter-intuitive, but the higher force requirements of the slower cadence results in the recruitment of more fast twitch muscle fibres, since these fibres are capable of producing more force than slow twitch fibres. The drawback is that fast twitch fibres consume more glycogen, and fatigue more quickly than slow twitch fibres. As result, over the course of a workout, fast twitch fibres will get depleted and will fatigue. More fast twitch fibres will need to be recruited as the duration increases, which results in an increase of the total number of muscle fibres activated.<?: prefix = o ns = "urn:schemas-microsoft-com:office:office" /> davetapson - readthis article: http://www.victorycycling.net/training/Cycling_Cadence.docI think it might help you get to grips with the principles involved in what you are questioning Link to comment Share on other sites More sharing options...
davetapson Posted December 17, 2008 Share Hmmm interesting - thanks Ronelle.So they figure that high cadence uses slow twitch fibres due to the fat that more fat is burned at high cadences. Still seems somewhat counter-intuitive...!!Another interesting thing is that they reckon optimum cadence for most athletes is 85 - 95 rpm - which I suspect is lower than most other 'advice' one gets... Link to comment Share on other sites More sharing options...
bruce Posted December 17, 2008 Share Okay, that document has a few misnomers. Fibre recruitment is more correlated with intensity (power as a percentage of VO2Max) than it is with cadence. This is because even at very low cadence, the forces in pedaling are significantly less than maximal muscle force. When googling for references on this topic, I found a very recent quote on the BikeRadar forums from Coggan, "An additional consideration here is that the minimal force at which a particular motor unit is recruited isn't fixed, but is dependent upon the speed of the movement (or actually, the intended speed of the movement). As a result, the pattern of motor unit recruitment is more closely related to the power output than it is to the cadence, and hence force, used to produce that power output. (IOW, pedaling faster doesn't necessarily reduce type II motor unit recruitment, because even though the force required to produce a particular power is lower, the minimal force at which type II motor units are recruited is also decreased.) " Link to comment Share on other sites More sharing options...
davetapson Posted December 17, 2008 Share I can go with what Bruce has said. The reason I posed the question is that I come from a long distance ( or should that just be 'slow' ) running background - has always made sense to me that my muscle make up is more of / better suited to slow twitch muscle fibre. I really struggle with high cadence riding - does not suit me at all, and I've tried to train it in as well. I can keep up 90 rpm no probs, but really struggle with anything higher, certainly for any length of time - which is what makes me question the high cadence = slow muscle twitch fibre theory. Bear in mind I'm not talking super high cadence here - for me, 100 is about as far as I can realisically go for anything else than short bursts. Seems to me that you recruit more fibres for the extra power, but I'm not sure I buy the slow twich / fast twitch theory. The paper derives this theory from the fact that fat is burning at high cadence - without having the experimental protocol, it's hard to know what they were measuring at what intensities. Link to comment Share on other sites More sharing options...
BikeMax Posted December 17, 2008 Share Why not stop worrying about it and just pedal at the cadence that gives you the greatest output for the duration that matters to you...haven't you got enough to worry about Link to comment Share on other sites More sharing options...
bruce Posted December 17, 2008 Share I was going to mention red herrings, but I'll leave that till later. Link to comment Share on other sites More sharing options...
TNT1 Posted December 17, 2008 Share make mine kippers on toast, ta. Link to comment Share on other sites More sharing options...
bruce Posted December 17, 2008 Share make mine kippers on toast' date=' ta. [/quote'] Smoked or boiled? Link to comment Share on other sites More sharing options...
TNT1 Posted December 17, 2008 Share smoked, please. Link to comment Share on other sites More sharing options...
Spinnekop Posted December 17, 2008 Share Eish boys....... I think BikeMax said it best.....just ride your bike.... Davetapson........Lance likes to do it fast....Ulrich did it slow.....both great riders...... Each to his own....... Link to comment Share on other sites More sharing options...
TNT1 Posted December 17, 2008 Share Davetapson........Lance likes to do it fast.... is that why he couldn't hang on to sheryl or those olsen twits? Link to comment Share on other sites More sharing options...
bruce Posted December 17, 2008 Share Eish boys....... ? I think BikeMax said it best.....just ride your bike.... ? Davetapson........Lance likes to do it fast....Ulrich did it slow.....both great riders...... ? Each to his own....... ? Exactly! Just imagine if Lance had been bust for EPO in 1999. Then the whole world would be riding big gears and low cadence, 'cos Uli would have been the greatest cyclist ever. Link to comment Share on other sites More sharing options...
THE BODY CENTRE Posted December 17, 2008 Share Bruce - why i posted that link (misnomers and all) is because it explains some basics principles - (and I do admit i chose an easy option, because once you google 'cadence efficiency twitch' -- the day disappears in reading!!) It sounded to me as if davetapson equals high cadence with fast twitch - as if he understand the 'faster (higher) cadence' to imply the use of fast twitch - thus missing the main point of difference (and therefore main use) of fast and slow twitch fibres ... And when I read his reply to your post it sounds as if he still believes that, so he is doesn't sound nearer to clarity on his original question, where he thinks he has been mislead with information. Maybe you have a link at hand where this is all explained in a way that clears the issue for him? Link to comment Share on other sites More sharing options...
BikeMax Posted December 17, 2008 Share Bruce - why i posted that link (misnomers and all) is because it explains some basics principles - (and I do admit i chose an easy option' date=' because once you google 'cadence efficiency twitch' -- the day disappears in reading!!) It sounded to me as if davetapson equals high cadence with fast twitch - as if he understand the 'faster (higher) cadence' to imply the use of fast twitch - thus missing the main point of difference (and therefore main use) of fast and slow twitch fibres ... And when I read his reply to your post it sounds as if he still believes that, so he is doesn't sound nearer to clarity on his original question, where he thinks he has been mislead with information. Maybe you have a link at hand where this is all explained in a way that clears the issue for him? [/quote'] How about this one.. http://sportsmedicine.about.com/od/anatomyandphysiology/a/MuscleFiberType.htm Link to comment Share on other sites More sharing options...
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