Re: t-and-f: Re: Fast twitch/slow twitch question?
I'll second this. I did some research as an undergrad where we were able to convert the muscle fiber type in mice from type 1 (slow) to type IIB (fast). This was the gastrocnemius muscle; there was no switching or trauma involed. We induced the conversion by completely unweighting the hind legs of the mice (they could still walk around, but did it using their front legs). Apparently in an atrophied state, the muscle reverts to fast-twitch type. What seems to be the case is that the natural, untrained muscle fiber composition is determined by genetics, as is the range of 'changeability' of muscle fiber type. For example, your average Joe might be 50% fast, but be able to range between 30 and 70% depending on what he's doing. Whereas an ultrarunner might be 90% slow and only able to get down to 80% no matter what he does. There is a significant amount of conversion that can take place, depending on workload. Now I don't know about conversion from fast to slow, so I can't speak to high school sprinters doing XC. But I wouldn't be surprised if it could change their muscle fiber composition. Paul On Sat, 5 May 2001, Ed Prytherch wrote: There was a report of an experiment in New Studies in Athletics (IAAF) a few years ago which appears to contradict this. The experimenters switched the soleus and gastrocnemius muscles in a dog. One of the muscles (I can't remember which) has a higher proportion of fast twitch fibers. At first the dog had difficulty walking, but after some time it learned to walk with the switched muscles. Muscle biopsies were performed after the dog had fully adapted. The muscle which had previously been predominantly slow twitch had become predominantly fast twitch and vice versa. Some sprint coaches (Loren Seagrave, Charlie Francis) are strongly opposed to young sprinters doing much endurance work because they think that there may be a conversion of fast twitch to slow twitch fibers. But Monique Henderson ran cross country! Ed Prytherch
Re: t-and-f: Re: Fast twitch/slow twitch question?
Paul - Great, informative post. I had not been aware of this research. A question, which may be more theoretical than scientific, will untrained fast-twitch muscles be able to sprint faster than trained slow-twitch muscles? And is it possible for a reasonably active person to change the composition of fibers significantly based on the type of training he does, or is it only by removing all stress on the muscle that the fibers revert to fast twitch? Is there any reseach that suggests that the fiber-switch that Paul observed in unweighted muscles could be stimulated in a more practical way? - Ed Parrot
Re: t-and-f: Re: Fast twitch/slow twitch question?
- Original Message - From: Ed Dana Parrot [EMAIL PROTECTED] To: 't-and-f@darkwing. uoregon. edu' (E-mail) [EMAIL PROTECTED] Paul - Great, informative post. I had not been aware of this research. A question, which may be more theoretical than scientific, will untrained fast-twitch muscles be able to sprint faster than trained slow-twitch muscles? Haile Gebreselassie has run the 1500m in 3.32 and the 10km in 26.31. I recall reading an interview three or four years ago with a local Dutch rag in which he said his best 100m time was around 11.2 or 11.3 seconds. This would be a very decent sprint time for the world's top female sprinters. As far as total muscle mass goes, Gebreselassie weighs about 55kg, which means that he is roughly about the same size as a top female sprinter. If his muscles are slow-twitch then they're pretty competitive in terms of power/weight against fast-twitch.
Re: t-and-f: Re: Fast twitch/slow twitch question?
So, for 20 million you could go into orbit and the zero G would convert your slow twitch to fast...Is that what Tito was doing? Tom - Original Message - From: Ed Dana Parrot [EMAIL PROTECTED] To: 't-and-f@darkwing. uoregon. edu' (E-mail) [EMAIL PROTECTED] Sent: Monday, May 07, 2001 11:58 AM Subject: Re: t-and-f: Re: Fast twitch/slow twitch question? Paul - Great, informative post. I had not been aware of this research. A question, which may be more theoretical than scientific, will untrained fast-twitch muscles be able to sprint faster than trained slow-twitch muscles? And is it possible for a reasonably active person to change the composition of fibers significantly based on the type of training he does, or is it only by removing all stress on the muscle that the fibers revert to fast twitch? Is there any reseach that suggests that the fiber-switch that Paul observed in unweighted muscles could be stimulated in a more practical way? - Ed Parrot
Re: t-and-f: Re: Fast twitch/slow twitch question?
On Mon, 7 May 2001, Elliott Oti wrote: Haile Gebreselassie has run the 1500m in 3.32 and the 10km in 26.31. I recall reading an interview three or four years ago with a local Dutch rag in which he said his best 100m time was around 11.2 or 11.3 seconds. This would be a very decent sprint time for the world's top female sprinters. As far as total muscle mass goes, Gebreselassie weighs about 55kg, which means that he is roughly about the same size as a top female sprinter. If his muscles are slow-twitch then they're pretty competitive in terms of power/weight against fast-twitch. This is a good point which is that we cannot peg an event to a specific fast to slow twitch muscle ratio. Said Auoita ranked #1 in the world at both 800m and at 10,000m. Late in his career Coe had planned on moving up to the 5,000 where he thought he could run between 13:00 and 13:15 (injuries forced him back to the 1500). I don't know about Gebresellasie but both Coe and Aouita (who says he based a lot of his trainging on Coe's) were distance guys (Coe was a 1500-3000m guy in high school) who worked out heavily with weights (aouita is reportedly said to have lifted every day) to increase their speed. There is certainly a lot we don't know about the mix of speed an endurance. Given the relatively little improvement in the 800 over the last 20 years it doesn't seem too many people are figuring it out. Regards, Paul
Re: t-and-f: Re: Fast twitch/slow twitch question?
--- Elliott Oti [EMAIL PROTECTED] wrote: Gebreselassie weighs about 55kg, which means that he is roughly about the same size as a top female sprinter. He's also roughly 9 inches shorter than *the* top female sprinter, but I doubt that has any relevance. Dan = http://AbleDesign.com - AbleDesign, Web Design that Can! http://Run-Down.com - 10,000 Running Links, Free Contests... @o Dan Kaplan - [EMAIL PROTECTED] |\/ ^- ( [EMAIL PROTECTED] or [EMAIL PROTECTED] ) _/ \ \/\ [EMAIL PROTECTED] (lifetime forwarding address) / / (503)370-9969 phone/fax __ Do You Yahoo!? Yahoo! Auctions - buy the things you want at great prices http://auctions.yahoo.com/
Re: t-and-f: Re: Fast twitch/slow twitch question?
Altitude training for sprinters? Dennis - Original Message - From: Tom Derderian [EMAIL PROTECTED] To: Ed Dana Parrot [EMAIL PROTECTED]; 't-and-f@darkwing. uoregon. edu' (E-mail) [EMAIL PROTECTED] Sent: Monday, May 07, 2001 12:57 PM Subject: Re: t-and-f: Re: Fast twitch/slow twitch question? So, for 20 million you could go into orbit and the zero G would convert your slow twitch to fast...Is that what Tito was doing? Tom - Original Message - From: Ed Dana Parrot [EMAIL PROTECTED] To: 't-and-f@darkwing. uoregon. edu' (E-mail) [EMAIL PROTECTED] Sent: Monday, May 07, 2001 11:58 AM Subject: Re: t-and-f: Re: Fast twitch/slow twitch question? Paul - Great, informative post. I had not been aware of this research. A question, which may be more theoretical than scientific, will untrained fast-twitch muscles be able to sprint faster than trained slow-twitch muscles? And is it possible for a reasonably active person to change the composition of fibers significantly based on the type of training he does, or is it only by removing all stress on the muscle that the fibers revert to fast twitch? Is there any reseach that suggests that the fiber-switch that Paul observed in unweighted muscles could be stimulated in a more practical way? - Ed Parrot
Re: t-and-f: Re: Fast twitch/slow twitch question?
There was a report of an experiment in New Studies in Athletics (IAAF) a few years ago which appears to contradict this. The experimenters switched the soleus and gastrocnemius muscles in a dog. One of the muscles (I can't remember which) has a higher proportion of fast twitch fibers. At first the dog had difficulty walking, but after some time it learned to walk with the switched muscles. Muscle biopsies were performed after the dog had fully adapted. The muscle which had previously been predominantly slow twitch had become predominantly fast twitch and vice versa. All this proves is that the body of the dog was incredibly adaptable when faced with the tremendous trauma of having it's muscles switched. This is not an entirely surprising discovery. It suggests that part of the definition of muscle type is related to the context of the muscle. Given that all the body's cells are broken down and recreated on a regular basis, and that none of the muscle cells you have today are actually the same cells you had three months ago in a literal sense, we should be even less surprised that as the body rebuilt cells, it did so the way it remembered they should have been. Now if you could trick the body into thinking that a fast twitch muscle belonged where a slow twitch muscle was, you'd have something. But if you could do that, you could probably trick the body into thinking that healthy tissue belonged where a malignant tumor was, which would be a pretty impressive feat. - Ed Parrot
Re: t-and-f: Re: Fast twitch/slow twitch question?
Netters Here is an example of what I consider a valuable contribution by Mr. Entine: The Mystery and Myths of Muscles Michael Rohl
Re: t-and-f: Re: Fast twitch/slow twitch question?
This is a topic that always interest me because there is not a clear answer. It seems as though there is a balance that is needed. Charlie Francis and Loren Seagrave seem flawed in their assessments given the results of athletes they have coached. Loren has not had a successful athlete since Dawn Sowell, and Charlie Francis is known for 2 things, steroids, and young athletes. The former needs no mention, the latter is the result of talent, not training. I have witnessed nothing that says you can "kill" fast twitch. From the results of our training I would definitely say there is some sort of balance needed. I will remain shallow in this discussion because it is far too scientific for my taste. I will continue to listen until I obtain enough information to speak about it (That will probably be tomorrow!LOL). DGS Faith is a road seldom traveled Let us run with patience the race that is set before us, looking unto Jesus, the author and finisher of our faith" Hebrews 12: 1-2
Re: t-and-f: Re: Fast twitch/slow twitch question?
I think Jon and the parents and the coach may have missed something about the school girls who were sprinters in the spring, ran cross-country and in the subsequent spring, could not sprint as well. I suspect they just grew. They got bigger and heavier and slower. The fiber type didn't change, just the load did. The science would know their weight before and after. Something which I we don't know. But that seems the simplest answer. Tom, who is much older, heavier, and slower. - Original Message - From: Jon Entine [EMAIL PROTECTED] To: t-and-f-digest [EMAIL PROTECTED]; Track and Field List [EMAIL PROTECTED] Sent: Saturday, May 05, 2001 8:33 PM Subject: t-and-f: Re: Fast twitch/slow twitch question? Paul: The coach and the parents of these girls do not know what they are talking about. Here's a few relevant paragraphs from Taboo. deleted stuff from Taboo, because you should have the book on your bookshelf. I coach cross country in the fall at one school and track in the spring at another school (very small). While watching some of the girls running the 4 x 400 relay (from the team that I coach cross country with, but not track), I saw some new faces that were running about 61 and 63 second splits. I made reference that we should try and recruit these girls for cross country in the fall to try and help rebuild our team (defending state champions). Some coaches and the parents of these girls heard me say this and ALL had the following response. If these girls run cross country they will lose their fast twitch muscles while developing slow twitch muscles. When spring comes around for track season, these so called sprinters will not be the same because they cannot regain the fast twitch muscles that they lost. The parents of these girls told me that their doctor had told them this theory when they had specificaly asked him the question. The parents are somewhat interested in having the girls run cross country, but don't want to see them run slower during track because of cross country. This same theory was also told to me from one of these girls coaches. He says that Time and time again he has seen sprinters join cross country in the fall to try and stay in shape, and then not be the same sprinter the following spring because of what cross country did to them. I would greatly apprecriate any research that has been done on the subject, and you may either reply to me privately or to the list. I'm not an expert on the fast twitch/slow twitch muscle thing, but based on numerous years of coaching and T F education I can't say that I agree 100 percent to their theory. Since I am not an expert, I am looking for those in the know to just clarify things for me. I'm not trying to prove anyone wrong, but I just want to be 100 percent positive on my facts when I present my case. :) Paul Nisius Bigfork, MN -- Jon Entine RuffRun 6178 Grey Rock Rd. Agoura Hills, CA 91301 (818) 991-9803 [FAX] 991-9804 http://www.jonentine.com
Re: t-and-f: Re: Fast twitch/slow twitch question?
There was a report of an experiment in New Studies in Athletics (IAAF) a few years ago which appears to contradict this. The experimenters switched the soleus and gastrocnemius muscles in a dog. One of the muscles (I can't remember which) has a higher proportion of fast twitch fibers. At first the dog had difficulty walking, but after some time it learned to walk with the switched muscles. Muscle biopsies were performed after the dog had fully adapted. The muscle which had previously been predominantly slow twitch had become predominantly fast twitch and vice versa. Some sprint coaches (Loren Seagrave, Charlie Francis) are strongly opposed to young sprinters doing much endurance work because they think that there may be a conversion of fast twitch to slow twitch fibers. But Monique Henderson ran cross country! Ed Prytherch - Original Message - From: Jon Entine [EMAIL PROTECTED] To: t-and-f-digest [EMAIL PROTECTED]; Track and Field List [EMAIL PROTECTED] Sent: Saturday, May 05, 2001 8:33 PM Subject: t-and-f: Re: Fast twitch/slow twitch question? Paul: The coach and the parents of these girls do not know what they are talking about. Here's a few relevant paragraphs from Taboo. The Mystery and Myths of Muscles ³Is the composition of muscle tissue of blacks different from that of whites?² asks a reader in a letter to Muscle Fitness magazine. ³To me, the muscle definition of black bodybuilders ... looks better than that of their white counterparts.² It certainly seems that something is going on. But is it a projection of white insecurities or something more substantive? For years it was axiomatic that performance differences were linked to muscle composition. It was believed that muscles have two types of fiberswhite, or fast-twitch, which were thought to be adapted for power movements, such as leaping or sprinting; and red, or slow-twitch, which were adapted for endurance. Now we know the model is slightly more complicated. There are in fact two different types of fast-twitch fibers, one more metabolically efficient. Whites on average have a higher percentage of slow-twitch fibers than West African blacks, who generally have more of both types of fast-twitch fibers. So what is the significance of these differences? Geneticist and exercise physiologist Claude Bouchard at Laval University in Quebec City, known as a guru on muscles and metabolism, has run numerous experiments comparing two populations, FrenchCanadian and West African students. Using long needles inserted into the thighs of test subjects, Bouchard¹s team extracted tiny sections of fibers, which look to the naked eye like pieces of raw meat. They were chemically treated to reveal metabolic differences, put on a glass slide, and slipped under a high-power microscope, where they appeared as a collage of tiny red and white crocodile scales. The West African subjects, by a ratio of approximately two to one, had more of the larger fast-twitch fibers. The researchers concluded that the force generating capacity of type-II muscle fibers at high velocity, the speed and tempo of movements, and the capacity of an individual to adapt to exercise training are all genetically influenced. Although physical activity can improve fitness, with a few caveats, it cannot alter a person¹s biological endowment by converting fast-twitch fibers to slow-twitch ones, or vice versa (although people do gradually and permanently lose fast-twitch muscles as a result of aging). It¹s estimated that 40 percent is due to environmental influences such as exercise, whereas 45 percent is associated with genetic factors (the remaining 15 percent is due to sampling error). At the far end of the performance bell curve in sprinting, where small differences can be crucial, genetics clearly circumscribes possibility. Note: Scientists have converted type I slow-twitch fibers to type II fibers with the use of long-term electrically induced contractions. And training can convert the less metabolically efficient fibers into more efficient onesfor instance, when trained athletes run so fast that they go into severe oxygen debt, forcing the muscles to use oxygen more efficiently. On 5/5/01 2:03 PM, t-and-f-digest [EMAIL PROTECTED] wrote: Date: Sat, 5 May 2001 09:08:16 -0700 (PDT) From: Paul Nisius [EMAIL PROTECTED] Subject: t-and-f: Fast twitch/slow twitch question? The following debate came up at a high school track meet last night and I am looking for some expert opinions on the topic. I coach cross country in the fall at one school and track in the spring at another school (very small). While watching some of the girls running the 4 x 400 relay (from the team that I coach cross country with, but not track), I saw some new faces that were running about 61 and 63 second splits. I made reference that we should try and recruit these girls for cross country in the fall to try and help
