well i tried to measure my bench 1 rep max and i figured out it was about 40 kg using the barbell bench press then i wait for like 5-10 mins then i tried to use 80% of my 1 rep max to see how much reps can i do i tried this twice one time i got 6 reps and 1 time i got 7 so do i have a fast twitching muscle fibers more than the slow ones or do i have balance between both cuz 6 is in the range of fast twitching and 7 is in the balanced ones any help please?

The only way to tell your actual balance between red and white muscle fibers is to have a genetic test like FitnessGenes that Scott talks about on this site. Muscular contraction/strength is a product of muscle fiber type, tendon and ligament placements, efficiency of the central nervous system, and glycogen levels in the muscle. As such, trying to acertain actual fiber amounts and ratios based on number of reps and rest periods is not possible.

 

If you don't want to invest in a FitnessGenes test, the only other way is with your training over time. If you train for 2 months doing low reps/high weight training with long rest periods and then train 2 months doing higher reps/moderate weight with shorter rest periods and then noting which method produced the most noticeable gains in size and/or strength. If the former causes the most results, you are white fiber dominant. If the latter does, then you are more red fiber dominant. If both produce relatively equal results, then you have an equal distribution of both. This will then give you insight into the best way to train to meet your goals based on your body muscle composition.

 

 

John

Hi John,

Did you invest in FitnessGenes test or did you do 2 months training to figure out what's the best for you?
If you did - how did it affect your training?

I did the FitnessGenes test. Ironically, it told me what I pretty much knew after 34 years of lifting :-) I wish something like that was around back in the early 1980's when I first started lifting as it would have saved me a lot of time.

 

John

Even when you know, what fibers are dominant, don't you have to train them all anyway? Perform training to train slow and fast twitch muscle fibers?

Yes, but very few people have a perfect 50/50 balance of red to white fibers. Most people have a dominant muscle fiber distribution. This is why on average bodybuilders are bigger than powerlifters and powerlifters tend to be stronger than bodybuilders. Bodybuilders train in the 6-12 rep range with moderately heavy to heavy weights and shorter rest periods which hits all 3 muscle fiber types: Type I, Type IIa, Type IIb. Powerlifters train in the 1-5 rep range with heavy weights and long rest periods. This focuses primarily on the Type IIb fibers.

 

Type I are red muscle fibers (slow twitch)

Type IIb are white muscle fibers (fast twitch)

Type IIa are a combo of both.

 

White fibers have the highest growth potential but the lowest endurance. Red fibers have the highest endurance but lower growth potential than white. Training in the 6-12 rep range hits them both and stimulates the most muscular fiber growth. If you are more red fiber dominant, then higher volume and reps will stimulate more growth. If you are more white fiber dominant, then lower reps with higher weight will stimulate more growth. You need to train all fibers but knowing what your make-up is will save you time by telling you which training style is best for your genetic make-up.

 

I can tell you it personally works. I am red fiber dominant with above average recovery and higher lactic acid clearance ability. This means I respond better to high volume training with more sets and reps and I have lower muscle fatigue due to higher lactic acid clearance rates. My workouts are all supersets/drop sets/giant sets with moderate heavy weights and low rest periods (30-60 seconds). I am done in 60 minutes doing full body Push/Pull style workouts 4-days a week. I am the leanest I have ever been and I have retained the same amount of strength I had in my 20-30s in my 50s relative to my age - my strength is not the same in absolute terms but rather relative terms.

 

John

Wow, this knowledge is gold! Or maybe platinum? ;)

Did you get all this information about you from FitnessGenes? Red fiber dominant, higher lactic acid clearance ability etc?
Would your recommend doing the test as a beginner?

Yes - the FitnessGenes test is very detailed and worth the money. If you can afford it, I highly recommend it - Beginner or otherwise.

 

John