T Nation

Slow Twitch Fibers and Neurotype

I have one questiom, Christian made video about corelation beetwen twitch fibers and neorotype. I have question can 1b have slow twitch fibers and be very good Natural athelete for example in running?

Yes, I actually answered a question about that recently.

There is a positive correlation between your neurotype and fiber type. But it’s a correlation not a causality and it is not always the case.

Fiber type is determined by your ACTN3 type. If you are a 1B but have more ACTN3 XX isoforms, you will have more slow twitch fibers. Just like a type 3, who is typically more likely to be slow-twitch dominant, can be fast-twitch dominant if they have more ACTN3 RR isoforms.

Is low lactic acid tolerance, good strength and explosive, but very rapid fatigue a sign of someone with a high rate of fast twitch muscle fibers? i am 2A “Passionate”

It absolutely is

Christian i have other question, can type 1A be introvert? Or its imposible

It should not be their natural state, no.

BUT a highly stressed 1A will become silent and more introverted. The 1A and 3 are actually very similar from a genetic and neurotransmitters perspective. The big difference is that 1A have high GABA and low glutamate and the 3 are the opposite, all other neurotransmitters are similar. So if a 1A depletes GABA for some reason he can start to act more like a type 3.

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So, on The other hand 3 can become 1A or it is impossible?

It’s unlikely as they would have to dramatically increase GABA and decrease glutamate. But it’s not impossible.

Thats very ineresting, so be increasing gaba you can become more extrovert?

By manipulating level of your neurotransimters you can become other person.

It’s not as simple as that. Learned behavior also plays a role. But yeah, changing neurotransmitters balance can influence personality.

Yes. Although my muscle, strength and explosive growth is quite fast, the number of reps in my exercises hardly increases ( I often train in 1 circuit), especially my isometrics holding time is always very low even with a small weight and it seems difficult to increase