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Fast Twitch or Slow Twitch?

Does anyone know…

Say you are using a weight that at full range you could get 4 reps…and you adjust the range so that you are getting 12 reps…would you be using Fast twitch type IIA fibers instead of IIB fibers?

or even more extreme…

you do partials with a very heavy weight, say 150% of max… for 20 - 30 reps with only a few inches of motion…

Are you then using slow twitch/fast twitch IIA?

Muscle fibers are recruited in order of need. From the slowest and weakest ones, to the strongest ones. Generally fast twitch fibers are recruited when lifting near maximal and maximal weights, also when you take sets to failure, more and more muscle fibers are recruited because of the need to, as more of the first muscle fibers recruited start becoming too fatigued.

And for the record, all this “pondering” really gets one nowhere. worrying about whether you are recruiting type IIA or type IIB fibers while you’re lifting is pointless, go out, lift heavy, and progress.

It’s only 150% in the sense that it’s 1.5x more tha you do in a full range of motion. When you shorten the movement fo a few inches, you essentially change it up and it’s a totally different exercise. So, if you can do 20-30 reps, you’re not gonna be recruiting tyep IIb from the get go, no matter how much weight it is relative to the full ROM movement.

Weight training generally causes a shift to a slower-twitch profile.

[quote]bballsavant wrote:
It’s only 150% in the sense that it’s 1.5x more tha you do in a full range of motion. When you shorten the movement fo a few inches, you essentially change it up and it’s a totally different exercise. So, if you can do 20-30 reps, you’re not gonna be recruiting tyep IIb from the get go, no matter how much weight it is relative to the full ROM movement. [/quote]

hmm i just don’t think one would be able to bang out 20-30 reps with 150% of their 1 RM, and if they are able to, then the ROM is just too ridiculously short to offer much.

[quote]Ryan P. McCarter wrote:
Weight training generally causes a shift to a slower-twitch profile.[/quote]

you got two things wrong here. 1st you got the myth backwards, the myth is that weight training causes muscle fibers to change from slow twitch to fast twitch. Second of all…it’s a myth anyway. you can’t transform muscle fibers from 1 type to another, the only thing is that with different types of training you can increase the volume of a certain muscle fiber type. You’ll have the same percentage of total muscle fibers, but the cross sectional area of one type that you’ve been training to develop, will be greater.

[quote]That One Guy wrote:
Ryan P. McCarter wrote:
Weight training generally causes a shift to a slower-twitch profile.

you got two things wrong here. 1st you got the myth backwards, the myth is that weight training causes muscle fibers to change from slow twitch to fast twitch. Second of all…it’s a myth anyway. you can’t transform muscle fibers from 1 type to another, the only thing is that with different types of training you can increase the volume of a certain muscle fiber type. You’ll have the same percentage of total muscle fibers, but the cross sectional area of one type that you’ve been training to develop, will be greater.[/quote]

No, he’s dead right. It’s a well known fact that partial range movements shut down motor neurons and inhibit them from doing their job. Something about the cross irrigation of muscular entropy effect.

True story. I swear.

[quote]No, he’s dead right. It’s a well known fact that partial range movements shut down motor neurons and inhibit them from doing their job. Something about the cross irrigation of muscular entropy effect.

True story. I swear.[/quote]

Ques que c’est le fuck?

[quote]That One Guy wrote:
Ryan P. McCarter wrote:
Weight training generally causes a shift to a slower-twitch profile.

you got two things wrong here. 1st you got the myth backwards, the myth is that weight training causes muscle fibers to change from slow twitch to fast twitch. Second of all…it’s a myth anyway. you can’t transform muscle fibers from 1 type to another, the only thing is that with different types of training you can increase the volume of a certain muscle fiber type. You’ll have the same percentage of total muscle fibers, but the cross sectional area of one type that you’ve been training to develop, will be greater.[/quote]

Kiss my ass, I’m not wrong at all. You’re reading too far into my post. If you want to be geeky (which I assume you do), you’re right, muscle fibers can’t change type, but to say they can’t change their characteristics is wrong, and if a type IIb becomes more like a IIa in its makeup and performs like a IIa, it’s a IIa to me, even though it’s still “technically” a IIb.

Secondly, it’s been documented that training of ANY type causes a shift toward a slower profile. The people who have the most fast-twitch fibers are couch potatoes. That’s not to say you can’t eventually alter your profile to be more fast-twitch, but the immediate response is a shift towards efficiency.

[quote]Ryan P. McCarter wrote:
That One Guy wrote:
Ryan P. McCarter wrote:
Weight training generally causes a shift to a slower-twitch profile.

you got two things wrong here. 1st you got the myth backwards, the myth is that weight training causes muscle fibers to change from slow twitch to fast twitch. Second of all…it’s a myth anyway. you can’t transform muscle fibers from 1 type to another, the only thing is that with different types of training you can increase the volume of a certain muscle fiber type. You’ll have the same percentage of total muscle fibers, but the cross sectional area of one type that you’ve been training to develop, will be greater.

Kiss my ass, I’m not wrong at all. You’re reading too far into my post. If you want to be geeky (which I assume you do), you’re right, muscle fibers can’t change type, but to say they can’t change their characteristics is wrong, and if a type IIb becomes more like a IIa in its makeup and performs like a IIa, it’s a IIa to me, even though it’s still “technically” a IIb.

Secondly, it’s been documented that training of ANY type causes a shift toward a slower profile. The people who have the most fast-twitch fibers are couch potatoes. That’s not to say you can’t eventually alter your profile to be more fast-twitch, but the immediate response is a shift towards efficiency.

http://www.ncbi.nlm.nih.gov/pubmed/10883005[/quote]

…soooo, you’re saying we should all quit lifting right now

Doesn’t matter…
you go heavy at first, you recruit fast twitch muscles. you do it long enough at the same weight and bang out more reps you’ll recruit slow twitch…

so just go out and train and do what you do and get better at it… worry about the science later…a 500lbs squat is going to beat a 200 page thesis.

[quote]Kiss my ass, I’m not wrong at all. You’re reading too far into my post. If you want to be geeky (which I assume you do), you’re right, muscle fibers can’t change type, but to say they can’t change their characteristics is wrong, and if a type IIb becomes more like a IIa in its makeup and performs like a IIa, it’s a IIa to me, even though it’s still “technically” a IIb.

Secondly, it’s been documented that training of ANY type causes a shift toward a slower profile. The people who have the most fast-twitch fibers are couch potatoes. That’s not to say you can’t eventually alter your profile to be more fast-twitch, but the immediate response is a shift towards efficiency.

[/quote]

HOLY SHIT. DID YOU ACTUALLY MANAGE TO READ THIS? I looked at it for two seconds and then my brain shut down out of boredom. I woke up in the hospital… having been technically dead for 5 minutes.

[quote]http://www.ncbi.nlm.nih.gov/pubmed/10883005

…soooo, you’re saying we should all quit lifting right now
[/quote]

Why can’t people on this site lose an argument gracefully?

[quote]duffyj2 wrote:

…soooo, you’re saying we should all quit lifting right now

Why can’t people on this site lose an argument gracefully?[/quote]

Because we’re all hardcore alpha males who are never wrong. Duh.

[quote]Hanley wrote:
duffyj2 wrote:

…soooo, you’re saying we should all quit lifting right now

Why can’t people on this site lose an argument gracefully?

Because we’re all hardcore alpha males who are never wrong. Duh.[/quote]

Uhhh… I like, knew that. You dick.

[quote]duffyj2 wrote:
Hanley wrote:
duffyj2 wrote:

…soooo, you’re saying we should all quit lifting right now

Why can’t people on this site lose an argument gracefully?

Because we’re all hardcore alpha males who are never wrong. Duh.

Uhhh… I like, knew that. You dick. [/quote]

because what kind of world would we live in if all alpha males lost gracefully? A boring peaceful world. Nobody wants that.

[quote]That One Guy wrote:
duffyj2 wrote:
Hanley wrote:
duffyj2 wrote:

…soooo, you’re saying we should all quit lifting right now

Why can’t people on this site lose an argument gracefully?

Because we’re all hardcore alpha males who are never wrong. Duh.

Uhhh… I like, knew that. You dick.

because what kind of world would we live in if all alpha males lost gracefully? A boring peaceful world. Nobody wants that.[/quote]

Isn’t it great that we’re ALL alpha males?

/irony

[quote]That One Guy wrote:…soooo, you’re saying we should all quit lifting right now
[/quote]

I don’t recall saying anything of the sort. I mentioned something that I thought was interesting which you thought was incorrect, and I gave you something to read which states otherwise. Any further extrapolation is your own.

[quote]Ryan P. McCarter wrote:
That One Guy wrote:…soooo, you’re saying we should all quit lifting right now

I don’t recall saying anything of the sort. I mentioned something that I thought was interesting which you thought was incorrect, and I gave you something to read which states otherwise. Any further extrapolation is your own.
[/quote]

I suppose the point i was trying to make is, yes you were right, but data is only relevant if you combine it with common sense. If you were to take the data straight then it would appear that we should all be couch potatoes because we’ll have more (larger) fast twitch fibers and be hyoooge, but we know that is not the case, so it can be concluded that going more slow twitchish isn’t such a bad thing

[quote]That One Guy wrote:
Ryan P. McCarter wrote:
That One Guy wrote:…soooo, you’re saying we should all quit lifting right now

I don’t recall saying anything of the sort. I mentioned something that I thought was interesting which you thought was incorrect, and I gave you something to read which states otherwise. Any further extrapolation is your own.

I suppose the point i was trying to make is, yes you were right, but data is only relevant if you combine it with common sense. If you were to take the data straight then it would appear that we should all be couch potatoes because we’ll have more (larger) fast twitch fibers and be hyoooge, but we know that is not the case, so it can be concluded that going more slow twitchish isn’t such a bad thing[/quote]

retreat