# % of Fast Twitch / Slow Twitch Fibers and Performance?

Discussion in 'Power Training' started by jeff828, Sep 16, 2008.

1. ### jeff828 New Member

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Hey Guys

First Question, is there a way to find out the percentage of fast twitch/slow twitch fibers a rider has?

Second question is, knowing the ratio of fast vs slow, if you have primarily fast twitch fibers, does anyone have any research and know what percentage can usually be converted over to slow twitch with the proper training to help with FTP, time trailing., etc and if this is relevant to know?
Or would it vary on what you started with, for example if rider A is a sprinter and has 90% fast twitch, 10% slow, he might only be able to convert 5-10% so he will be limited on how much benefit he can get from those fibers, VERSUS rider B who has 60% fast and 40% slow, he might be able to convert up to 20% with proper training , in return become a better road racer, TTer, and will be able to raise their FTP numbers way more than the sprinter can.

Marty Nothstein is a good example, he is a pure sprinter, has won everything on the track, he switched to road racing, did the training but his performances were fair. So if he told his coach that he wanted to win the world TT championships would it be almost impossible because he would not be able to convert that many type2 fibers over that would be needed to do a sub 50min.
Mcewen/Boonen are another example of sprinters, do you think their ratio is not as wide as marty’s and this is possibly why they do better in road races.

Last question, anyone have any research on the above questions and if so can it be correlated to watts, like if a sprinter converts “x” % of those fast twitch fibers he will only add “x” more watts to his FTP?

I am 40, a sprinter, been racing 10+ years, came from bmx, 160lb, can hit 1200-1400w pretty easy, FTP is stuck around 260w, it has increased about 50w over the past 2 years of doing structured workouts, 2x20s etc, is it a reasonable to think I can get a FTP of 325w or even 300w or am I totally off the wall? I race cat 3, can be active and finish top 15, but that’s not good enough, I race the masters 123, can be active and place top 20, sometimes top 10 but that’s not good enough either, how do I play with these guys that have a FTP of 325-350w and get in the top 5, I am sure I can beat these guys in a heads up sprint but getting to the end of the race with more in reserve has been the issue.

Thanks

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2. ### xntrickly New Member

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I posted the same question with a couple of friends who really know things. You and I could be twins except that I am recently turned 45 and weigh about 10 pounds less than you. You probably also have very quick recovery from your efforts and are not a lot of fun to have in a paceline for that reason.

There answer to me was yes I could get my FTP up there. I've been doing this for a year on 10 hours/week but I try to do a couple 20 minute TT efforts twice/week and some extended pulls (e.g. 5 mins) when in group settings all at upper level 3/lower level 4. When I do the power by zones feature in trainingpeaks it shows that I have not done as much of this as I think I have and so I am going to really focus on Sweet Spot Training for the winter including hill repeats that are about 16-17 mins depending on conditions. Did it the past weekend and for the day I had a TSS of 250-ish so I'm still suffering...

I say all of this to encourage you. Feel free to PM if you like.

best regards.

3. ### germanboxers New Member

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Sounds like we could be triplets, except I'm the fat brother with crooked teeth. I'm 41, best 5s power of 1400w and best 1s of 1620w, but I weigh 185lbs. Unfortunately, my FTP is only 260w.

Is it possible to significantly change one's power profile? I would feel comfortable giving up 200w of 5s power if I could gain 40+w of FTP. It would certainly make me more competitive in the racing and riding I do. If possible, what is the prescription: long metacycles of 2x20's, SST, Tempo? Should sprinting be put on hold and only pulled out of the training bag nearer a big race?

Thanks

4. ### xntrickly New Member

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Hell we're all related!!!

I stopped doing sprints except once in a while for the "all important" city limits sign!!! I actually don't care to sprint anymore and would prefer to try and get away and then sprint.

I have been doing a lot of long pulls at threshold power and then above into Vo2 max land and then get back in the group. Now after my pulls and after I have recovered I am sitting up and sitting in the wind so that I do not get as much of a break as if on a wheel. I've only been doing it for a couple of weeks though... the power distribution chart shows considerable change though as I am spending a lot more time in zone 3 and 4 and my daily TSS scores have gone up (I do the same ride most days at lunch and then longer stuff with hill repeats on the weekend). Just this week I had an hour at NP250 but going uphill I sustain NP295 for 17 mins so I have my FTP "calculated to be 255". I plan on doing SST all winter and expect that should go up to 275...

I've only got so much time to ride so plan on just really getting as much as I can in zone 3 and 4. Hope this helps.

5. ### germanboxers New Member

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Thanks...yes it does help. Unfortunately for me, I believe my wide shoulders and low ftp/kg makes it impossible for me to "get away". My main goal is to be fresh enough to challenge a sprint, to not have a bad case of the "spongy legs" for the last half of a race all the time.

I'm going to try the same this winter...zone 3 and 4 whenever I can.

Thanks.

6. ### jeff828 New Member

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Hey isnt this interesting, we are probably all good sprinters and we have about the same FTP, is this a pattern among sprinter types? can we really see a 300w FTP while maintaining our sprint power? and on 8-12hrs of training, or do we need to quit our jobs and get 15-20hrs

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