T Nation

Slow vs Fast Twitch?


If I can do close to 90% of my 1 RM
for 10 x 3, does that mean I'm fast/slow
twitch dominant or is it related to
something else?
If I'm fast/slow dominant, what type of workouts would be best for me?


I believe it means that you are a slow twitch.


it also means that you're small, weak, and beginning. exactly zero weak, small beginners could be classified as 'fast-twitch.'

dont worry about 'fast-twitch, slow-twitch' stuff. non-stupid, consistent and progressive strength and speed training will make anybody 'fast twitch.'


How could you possibly know that.
answer: you can't
so stfu


Honestly, not very helpful. Given the fact that you have no way of knowing my #s and where I started, maybe you just get off on being dismissive. I'm not looking for an easy way to train, I simply want to make my programs as effective as possible.


Generally if you can only do 3 reps at 80% you're predominantly fast twitch (in the involved muscle groups), and you can do over 10 (this # might be low) you're predominantly slow twitch. Chances are you're around 50/50 like most people.


I don't think there is a really easy way to tell that works effectively unless your composition puts you at one of the extremes. The best you can do is judge your performance over time and assess whether your performance characteristics have moved in that direction.

I know from my own performance that I have more fast twitch characteristics now after several years of training the way I do, but putting any sort of number on that isn't feasible without having myself stuck by a needle. The 80% measure would indicate that I've swung more than is realisticly possible when in fact I just have shitty anaerobic conditioning due to low rep training.

Just focus on your end results. Fiber conversion methods should be used if they achieve your goal in terms of performance and discarded if they don't. The actual % of fibers and volume of each doesn't really change much in terms of how you should behave.


If you are losing sleep over your muscle fibre type, either you are a beginner or very advanced.

Train hard,



Great to see you posting again, Troll!

If I were exposed for creating multiple accounts and using them to back myself, I would definetly get a new account.

You really do have cojones,



fair enough. unless you tell me where you started and your current numbers i'll not know. although, from personal experience, only beginners care about what fiber type they are.

anyways, i doubt that you're slow twitch. does anybody even realize how maximally weak slow twitch is? slow twitch people are that way because they're really small and do crazy length endurance stuff. if they lifted then after a while they would cease to be slow-twitch.

and, yes, i do appreciate dismissiveness. it's kinda how i imply that your question is one that will only be helpfully answered if you just stop caring about the answer. especially since it's not even a proper question in the first place.

P.S. you posted in the "Beginners" section. am i to assume that you're an advanced lifter?


There are some studies out that show that it is easier to convert muscles that are fast twitch into slow twitch. I have not read any that report a switch from slow twitch to fast twitch.

Doesn't mean that they don't exist, I might have missed them.

I think the bottom line is that you should train for whatever desired effect you want, regardless of your fiber type.

And from what I have read about 80% of all people have about a 50/50 fast/slow split anyway. So you are most likely a combination of both.


yes, slow have never converted to fast. and yes, fast can convert to slow, but that takes some hardcore endurance stuff. i believe so much so that only those actually trying to optimize slow twitch qualities will get the conversion.

the reason that some people can be considered slow twitch dominant is not because fibers have converted, but because they've atrophied much of their fast twitch. this is why everybody can be fast twitch if they train to be.

and, yes, everybody is a combination of both. to what degree, i dunno.


A good way to tell if you are fast twitch dominant is think about when you were a kid. Were you faster than most of the kids in the schoolyard...jump among the highest, stronger? First pic for most of the sports?


Gotta have a say on this, as it reminds me of me starting out on my "get fit" quest 3 years or so ago. :slight_smile:

The responses you have seen here that you are presently dominated by slow-twitch fibers are correct. Why that might be is a different question, but it's an important one if you're developing a training program.

How have you worked out in the past? Endurance exercise, for example, will create a slow-twitch dominance (i.e. running, rowing, cycling at constant speed for extended periods (30+ minutes several times each week)).

Frankly, that's not as important as what you want to be, so what are your goals?

There's a moderately strong likelihood that whatever your goals are, lifting pretty heavy weights (75-95% RM or so) 2-3 times per week, then rinsing and repeating every week will (re)program your slow-/fast-twitch ratios, and make healthy compositional changes (improvements?) to your body.

Assuming your goals are to become leaner (and maybe even larger - but not fatter) then following any one of the myriad of training programs on here will yield excellent results - possibly in short order. The speed of improvement will be related to your past: if you've lifted heavy weights all your life, then the improvements will probably come slowly.

If, however, you've either been a slug all your life, or if you've only done low intensity cardio then you will probably respond dramatically to a program that involves strength-training and/or high-intensity cardio.

However, if your goal is to run a marathon or six, then you will still have to keep the endurance cardio stuff going - and for the gruelling long sessions, too. This will virtually, if not exactly, mitigate the effects of a strength-training program, making it arguable as to whether you should even bother (some say everyone benefits from strength-training. I personally agree with that).

So, as you can see, it really comes down to your medium term goals - can you share these?

Good luck! :slight_smile:



WiZlon and others, thanks for the responses.

My background is that in highschool and junior high I wrestled, and then did shotput my senior year of highschool. I started to weight train semi-seriously my sophomore year of highschool.

I believe I started out with 40x2 dumbbells on bench press when I was 14 or 15 and am now up to 90s. The summer of my sophomore year I was given an introductory weight training program by one of the strength coaches of LeHigh university, where I attended a wrestling summer camp. Basically 2-3 sets of 8-12 reps, full body, three days a week. The primary goal was to strengthen and adapt my connective tissues.

Right now i'm about 6'2 and 185 pounds depending on how much food I have in me, etc.

I'm a freshman in college, and my goals are to put on about 20 pounds of LBM within the next couple of months.

Right now I'm starting ABBH I.

I'm not sure what my max bench press is; I'd say somewhere around 200 pounds. I'm not a big BB bencher, so i'm expecting to see some pretty quick gains there. My Barbell row is pretty proportional to my bench press as well, so that's not a real issue. My deadlift is somewhere around 325 and I've only been doing them for two months or so, and I'm really not sure where my squat is. I had been doing 225 for 10 x 3, but increasingly (and chronically) tight hip flexors put me out of commission for a little while.

Right now i'm stretching those and working on my front squats and wrist flexibility.