|Does Lance Spin Because...||QUiTSPiNiNArOuND|
May 27, 2002 1:07 PM
|He has more fast twitch muscles, therefore using them to his advantage? And is there away to get moere slow twitch or fast twitch muscle fibers by training for em' or are they pre-determined?|
|re: Does Lance Spin Because...||filtersweep|
May 27, 2002 1:53 PM
|Actually, wouldn't SLOW twitch muscles be more condusive to spinning? I always understood fast twitch to be the power muscles with less endurance. I'd expect a masher to have more fast twitch muscles (more power).|
May 27, 2002 3:34 PM
|If you train for high cadence intervals up hills as well as other terrain you can generate the same amount of power as anyone else by using less energy. There for you end up with more energy by the end of the race. I raced cat 4 this sping and im turning cat 3 soon and it took me all winter to train for high cadence and its really hard to maintain on steep climbs like Lance does. But, it has worked REALLY well for me and I am 3-4mph faster than I was last year and I never rarely feel anything like shin splints or something of the like from pushing my legs to hard. I usually feel much better in fact and my LT is higher as well. I highly recommend it but it takes awhile to remind yourself to keep your legs spinning high revs but it feels very good and keeps you warm during the cold spring months. Also, my acceleration picked up alot on hill attacks due specifically to high cadence drills.|
|fast twitch vs. slow twitch||theBreeze|
May 27, 2002 4:21 PM
|An individual's relative proportion of fast twitch (Type IIb) and slow twitch (Type I) muscle fibers is set by genetics. The difference between the two is that Type IIb fibers generate contractions ANAEROBICALLY and Type I are AEROBIC fibers. Spinning lower gears allows one to stay in an aerobic state and therefore fatigue less quickly. It's not so much that Lance necessarily has a high proportion of slow twitch, but that he may not have the high relative number of fast twitch that give sprinters and big gear mashers their edge in highly anaerobic endeavors.
There is a third type of fiber, Type IIa, which can use either aerobic or anaerobic metabolism. Which system predominates depends upon what an individual's training focus is. If you train primarily high intensity, short duration (ie: 100 yd dash) then they will act more like Type IIb. Train with an endurance focus (ie: marathons) and they will behave more like Type I fibers.
Relative to true short burst, high intensity athletes, Michael Johnson for instance, I don't know that anyone in the pro peloton would be a pure "fast twitch" type athlete. Not if you can ride 200 km and then sprint out at the end. Heck, even Cipo can climb mountains, thank you very much. Not a fast as Armstrong, but probably faster than any of us.
Okay, the exercise phys lecture is over for today. Please read pages 100-175 in your text and be ready for a quiz on Friday!
|Dear Mr Science||lnin0|
May 27, 2002 6:14 PM
|Unrelated to the original post but I was curious to know if there is a way an individual can determine what type of muscle they have the most of. And don't just say it depends on what your good at because I am average at everything.
|If it's really improtant to you...||hayaku|
May 27, 2002 6:37 PM
|You can go to a sports medicine clinic and have a biopsy done. Not much fun though, and not a heck of a lot of use.
You should be able to get a good idea about what you need to focus on in training by race results and club rides though. If you are lacking in a certain area it will show up at these times. Or you can get an experienced onlooker to help with these judgements.
|Yep, biopsy is the only way. (nm)||theBreeze|
May 27, 2002 7:10 PM
|I read somewhere ....||McAndrus|
May 28, 2002 4:30 AM
|I hate it when I can't remember a source. But a few months ago I ran across a source for determing which fiber type dominates in your body.
I remember the jump test. In my younger (much younger) days, I was a basketball player and a very good jumper. At 5'11" I could reach the rim but couldn't get the extra 3 inches to stuff the ball. Occasionally I would take a rebound with my wrists above the rim.
So what? The source said that good jumpers have a lot of fast twitch muscle. In cycling terms that would make me a natural sprinter, which is too bad as I've always admired the climbers more and wish I could be one.
By the way, those jumping days are long, long gone.
|re: fast twitch vs. slow twitch||cyclopathic|
May 28, 2002 9:59 AM
|there's some references that given proper training amount of slow twitch can be increased, but fast twitch cannot (though you can increase the amount of mitochondria in fast twitching fiber). Yes genetics predefine proportions, training important still more.
With respect to higher cadence the dynamics of stroke and proportion of muscles used at higher cadence are different. Spinning utilizes more secondary muscles and unless you specifically train for high cadence there would be significantely higher % of fast twitching fiber utilized.
|re: Does Lance Spin Because...||bic|
May 27, 2002 4:22 PM
|Brcause he has spent years training to spin like he does. He used to mash and win sprints. He no longer wins sprints, can't remember last time he did. But can drop almost anyone going up big hills. His body comp. also changed since pre cancer, but has worked since on his spinning tech.|
May 27, 2002 7:54 PM
|My limited research on this subject through various articles leads me to believe that because of the latest devices for measuring watts and power by things like the SRAM Power meter some coaches are finding that the most power and efficiency comes from high cadences.
I think Lance and his coach watch these numbers and find a cadence that seems to produce the best power and then run it in the real world and it seems to work well for them.
The last TT I saw Lance ride a couple weeks ago looked like he was spinning too fast. Turned out he was like the second fastest, or so, and he seemed like he could've turned a bigger gear if he really needed the win whereas I'm sure the other riders went all out.
May 28, 2002 4:49 AM
|within the range of cycling cadences, say about 50-120rpm, the speed (rpms) probably has very little to do with what types of fiber are being recruited. There is some evidence that during very explosive, high speed tasks, there is selective recruitment of fast-twitch fibers but otherwise what fibers are recruited is much more related to the FORCE being generated. Your central nervous system works in terms of motor units, not muscle fibers per se. A motor unit is the alpha motor neuron in the spinal cord and all the muscle fibers (cells) it innervates. All of these cells from a given motor unit are typically of the same type (which can vary depending on what classification system your using). For our purposes human limb muscles possess three motor unit or fiber types. In terms of motor units there are Slow, Fast Fatigue-Resistant, and Fast Fatiguable which are made up (for the most part) of Type I, IIa or IIx fibers respectively. The IIx used to be called IIb's which makes everything a little more confusing.
Now, here's the critical part, Slow motor units with Type I fibers tend to be small (and therefore produce less force) whereas Fast-Fatiguable (Type IIx) units tend to be large and produce alot of force per motor unit. Also, Type I fibers tend to have about a 10-fold higher oxidative capacity than Type IIx fibers (which tend to have a very high glycolytic ability). Anaerobic and aerobic are really not good terms, since ALL muscle cells can use both oxidative and non-oxidative (glycolytic) pathways for energy production, only their relative maximum rates for one or the other vary greatly.
So, when your CNS recruits a muscle it does so based on the Henneman Size Principle, where small motor units are recruited first and then progressively large motor units are brought if higher forces are needed. Remember small motor units tend to be Slow, Type I. Makes sense that these units would be very fatigue resistant since you are using them all of the time (like for walking). Now if you sprint you will still be recruiting these Slow, small units but you will bring in the Fast, Fatigue-Resistant units as well, and if you jump you are probably recruiting just about every motor unit.
Now with endurance training the main adaptation is to increase the oxidative capacity (and glycolytic capacity to a lesser extant) of ALL of your muscle fibers. So even your type IIx, Fast-fatiguable units will become more fatigue resistant but relative to your slow units they will still fatigue much more readily.
There is some evidence that your muscle fiber composition can change with endurance training, it can certainly change with extreme situations (spaceflight, spinal cord injury, chronic electrical stimulation), but it's probably not all that significant under normal circumstances.
So back to Lance...If a cyclist is producing 300 watts he can do that 2 ways. Spin fast (less force/more frequent contractions) or mash (more force/less frequent contractions). So, since motor unit recruitment is based on force, for arguements sake, lets say the spinner will be using the small and intermediate sized motor units more frequently, whereas the masher will be using all of the motor units less frequently. The former will be relying on motor units that can repetively generate their force relying mainly on oxidative mechanisms because their oxidative capacity is so high, whereas the latter will be using these motor units as well (but at a slower rate, so probably no where near their maximum oxidative capacity) and the fast, fatiguable units which have low oxidative capacity and therefore must use glycolytic metabolism. That's why Lance spins, so he can rely more heavily on oxidative mechanism and less so on glycolytic energy (which is measured in terms of Lactic acid in the blood).
So don't confuse high rpms with fast-twitch muscle recruitment, actually just the opposite is true if you control for power output, at the high rpms you rely more on slow-
|Very well said! You can teach the next class:)(nm)||theBreeze|
May 28, 2002 5:43 AM
|did your post get cut off at the end?||Tig|
May 28, 2002 8:44 AM
|If so, please post the rest of it. This is great information. Thanks!|
May 28, 2002 9:18 AM
|I don't know what I was going to say.
It's a very confusing subject because things aren't black and white and there are several ways of typing a muscle fiber some of which are continuous rather than discreet types. Without going into how a muscle contracts it's not really possible to understand the different typing techniques. But I think a little too much emphasis is given to sprinters being fast-twitch guys, whereas Lance can't win a sprint because he has all slow-twitch fibers. I doubt anyone knows this for a fact. As someone else alluded to, even a sprinter like Cipollini has a phenomenal aerobic capacity, he is sprinting after 6 hours of riding not fresh like a track 200m guy. As to why some guys can sprint and some can't, it may have something to do with fiber type, but probably alot of other things, maybe some neurological, certainly it somewhat has to do with muscle size which probably affects absolute short term power production. Almost all of the sprinters in road cycling are big men with huge quads (Cipollini, Svorada, Lombardi, McEwen, and Tchmil or Museeuw who were once sprinters). And if you look at track sprinters they're even bigger, so if I was going to talk about some physiologic characteristic of sprinters I'd be much more inclined to attribute some of their ability to muscle size rather than muscle type.