“The proportion of type I fibres decreased from 57 to 48%”. I find this very interesting. Most of these studies do show an increase in type 2A fibres, but only from the conversion of type 2B to type 2A. This study showed a DECREASE in type 1 and subsequent increase in type 2A, indicating that the type 1 fibres converted to type 2A.
What can be taken away from this study? Notice the extremely long rest intervals between each sprint, up to 20 minutes. This is why I always feel that “conditioning” work (walk back recoveries between sprints etc) is useless for increasing sprint speed unless you are severely out of shape. If you want to actually get faster then you need to go low volume with full recoveries between efforts (1 minute per 10 metres at least).[/quote]
Just note that they fudged their stats in a number of ways.
They also didn’t provide enough information to effectively evaluate their analytical method.
Because of this, I take their results with a grain of salt.
“The proportion of type I fibres decreased from 57 to 48%”. I find this very interesting. Most of these studies do show an increase in type 2A fibres, but only from the conversion of type 2B to type 2A. This study showed a DECREASE in type 1 and subsequent increase in type 2A, indicating that the type 1 fibres converted to type 2A.
What can be taken away from this study? Notice the extremely long rest intervals between each sprint, up to 20 minutes. This is why I always feel that “conditioning” work (walk back recoveries between sprints etc) is useless for increasing sprint speed unless you are severely out of shape. If you want to actually get faster then you need to go low volume with full recoveries between efforts (1 minute per 10 metres at least).[/quote]
Just note that they fudged their stats in a number of ways.
They also didn’t provide enough information to effectively evaluate their analytical method.
Because of this, I take their results with a grain of salt.
[/quote]
Although the evidence for fibre transformation of type 1 to type 2a is not great, I still would not rule it out completely. It has been shown to occur in animals multiple times along with hyperplasia.
Remember hyperplasia? It was thought that it would be impossible for that to occur in human beings. Now it is generally accepted that the right type of training can produce hyperplasia in human muscle. Through hyperplasia alone, you can change the % slow to fast in a muscle group, however that doesn’t involve converting one fibre type to another.
“The proportion of type I fibres decreased from 57 to 48%”. I find this very interesting. Most of these studies do show an increase in type 2A fibres, but only from the conversion of type 2B to type 2A. This study showed a DECREASE in type 1 and subsequent increase in type 2A, indicating that the type 1 fibres converted to type 2A.
What can be taken away from this study? Notice the extremely long rest intervals between each sprint, up to 20 minutes. This is why I always feel that “conditioning” work (walk back recoveries between sprints etc) is useless for increasing sprint speed unless you are severely out of shape. If you want to actually get faster then you need to go low volume with full recoveries between efforts (1 minute per 10 metres at least).[/quote]
Just note that they fudged their stats in a number of ways.
They also didn’t provide enough information to effectively evaluate their analytical method.
Because of this, I take their results with a grain of salt.
[/quote]
Why do you think the stats are fudged?[/quote]
They performed the proper analysis and only got one significant difference (a slight increase in type IIA in one group only). So they decided to pool the subjects from two different experiments. This is NOT good science.
Furthermore, I read the immunohistochemistry article they referenced for their methods and if they really used that method it is more of a joke that I thought. Basically they looked at the slides under a microscope and gave them a rating between 1-5 (subjectively). This was the basis for their ‘quantitative analysis’
“The proportion of type I fibres decreased from 57 to 48%”. I find this very interesting. Most of these studies do show an increase in type 2A fibres, but only from the conversion of type 2B to type 2A. This study showed a DECREASE in type 1 and subsequent increase in type 2A, indicating that the type 1 fibres converted to type 2A.
What can be taken away from this study? Notice the extremely long rest intervals between each sprint, up to 20 minutes. This is why I always feel that “conditioning” work (walk back recoveries between sprints etc) is useless for increasing sprint speed unless you are severely out of shape. If you want to actually get faster then you need to go low volume with full recoveries between efforts (1 minute per 10 metres at least).[/quote]
Just note that they fudged their stats in a number of ways.
They also didn’t provide enough information to effectively evaluate their analytical method.
Because of this, I take their results with a grain of salt.
[/quote]
Why do you think the stats are fudged?[/quote]
They performed the proper analysis and only got one significant difference (a slight increase in type IIA in one group only). So they decided to pool the subjects from two different experiments. This is NOT good science.
Furthermore, I read the immunohistochemistry article they referenced for their methods and if they really used that method it is more of a joke that I thought. Basically they looked at the slides under a microscope and gave them a rating between 1-5 (subjectively). This was the basis for their ‘quantitative analysis’
Overall, the article is crap[/quote]
So they got no change in the % slow twitch at all? So they are blatantly lying about their results? I’ll have to take your word for it as I only have access to the abstract.
However I still stand by my last post in saying that fibre conversion from type 1 to type 2A is possible under the right conditions.
“The proportion of type I fibres decreased from 57 to 48%”. I find this very interesting. Most of these studies do show an increase in type 2A fibres, but only from the conversion of type 2B to type 2A. This study showed a DECREASE in type 1 and subsequent increase in type 2A, indicating that the type 1 fibres converted to type 2A.
What can be taken away from this study? Notice the extremely long rest intervals between each sprint, up to 20 minutes. This is why I always feel that “conditioning” work (walk back recoveries between sprints etc) is useless for increasing sprint speed unless you are severely out of shape. If you want to actually get faster then you need to go low volume with full recoveries between efforts (1 minute per 10 metres at least).[/quote]
Just note that they fudged their stats in a number of ways.
They also didn’t provide enough information to effectively evaluate their analytical method.
Because of this, I take their results with a grain of salt.
[/quote]
Why do you think the stats are fudged?[/quote]
They performed the proper analysis and only got one significant difference (a slight increase in type IIA in one group only). So they decided to pool the subjects from two different experiments. This is NOT good science.
Furthermore, I read the immunohistochemistry article they referenced for their methods and if they really used that method it is more of a joke that I thought. Basically they looked at the slides under a microscope and gave them a rating between 1-5 (subjectively). This was the basis for their ‘quantitative analysis’
Overall, the article is crap[/quote]
So they got no change in the % slow twitch at all? So they are blatantly lying about their results? I’ll have to take your word for it as I only have access to the abstract.
However I still stand by my last post in saying that fibre conversion from type 1 to type 2A is possible under the right conditions.[/quote]
They saw changes, but it didn’t reach significance.
They manipulated their data post-hoc to show significance. Not lying, but not good practice either.
However, the over riding factor is that their methods have a huge margin of error.
I am only commenting on this study though. I haven’t researched enough to have an opinion either way at the moment.
[quote]LiquidMercury wrote:
No. The fiber itself cannot change. It can however, take on certain properties of different fiber types over an extended period of time (think of - FT taking on properties of LT fibers in olympic endurance runners or rowers). Massive amounts of volume over YEARS can force these physiological changes/adaptations but the fiber itself does not change and without the consistent stimulus, the fiber will take on more and more of it’s original properties.[/quote]