How to find your muscle fiber type.

[Doug]

Ever wondered why a muscle isnt growing....

A normal person has a 50/50% split between fast twitch and slow twitch muscle fibres. But some people can have a predominance of fast or slow twitch muscle fibres. But how do you find out what is your muscle make up, so that you can alter your training to suit you muscle fiber type...

It is quite common to have a slightly predominant muscle fibre type, thats why professional athletes are good at what they do, long distance runners are predominently slow twitch, bodybuilders are mostly fast twitch. But to find out the fiber type in a particular muscle takes time to sort out..

How to find your muscle fiber composition.

The objective of the muscle fiber test is to determine the fiber composition of the muscles being used for a particular exercise. Two test protocols are described: The Dr F. Hatield muscle fiber test and the Charles Poliquin muscle fiber test.

Required Resources:
To undertake this test you will require:

Weight training facilities
An assistant/spotter
Selection of exercises

How to conduct the Dr F. Hatfield muscle fiber test:

Determine your one repetition maximum (1RM) on an exercise
Rest for 15 minutes
Perform as many repetitions as possible with 80% of your 1RM
Analysis:

Less than 7 repetitions – Your fast twitch (FT) dominant
7 or 8 repetitions – You have a mixed fiber type
More than 8 repetitions – You are slow twitch (ST) dominant
If you are FT dominant, then you should use heavier loads and lower repetitions predominantly in your training. ST dominant individuals, on the other hand, will respond better to lighter loads and higher repetitions

How to conduct the Charles Poliquin muscle fiber test:

Determine your one repetition maximum (1RM) on an exercise
Rest for 15 minutes
Perform as many repetitions as possible with 85% of your 1RM
Analysis:

Less than 5 repetitions – you are fast twitch (FT) dominant
5 repetitions – you have mixed fiber type
More than 5 repetitions – you are slow twitch (ST) dominant
If you are FT dominant, then you should use heavier loads and lower repetitions predominantly in your training. ST dominant individuals, on the other hand, will respond better to lighter loads and higher repetitions.

[Saurus]

A most useful post!

rep +

[delaroche]

if you are dominant to either fast or slow, do the rep/weight changes go more towards the strength/'toning' ways....

ie. let's say normal muscle growth = 8-12 reps.
would FT then move into the strength reps (4-8) or (6-10).

oh, and does FT/ST have different affects in terms of the ability to gain muscle and/or strength?

[Damien]

Excellent post Doug, here, have some rep!

[zeph]

v. good post doug, sure it will be very useful to many people, even if only for the intrest side. rep+

[Doug]

Originally Posted by delaroche

if you are dominant to either fast or slow, do the rep/weight changes go more towards the strength/'toning' ways....

ie. let's say normal muscle growth = 8-12 reps.
would FT then move into the strength reps (4-8) or (6-10).

oh, and does FT/ST have different affects in terms of the ability to gain muscle and/or strength?

Slow twitch muscle fibers are the endurance fibres and dont grow bigger like the fast twitch fibers.

If you have a greater number of slow twitch fibers then to affect the greatest number of fibers you will have to use higher reps (!2-15), shorter rest periods, and higher volume(more sets). Slow twitch fibers recover quicker, take longer to fatigue, and require more work to maximise growth. Slow twitch fibers are limited in the potential for growth. Remember also that you will still need to do some lower rep training to maximise the fast twitch fibers in that muscle.

If your muscles have a fairly even mix of fibers, you can evenly divide your training between focusing on the lower rep, fast-twitch fiber training and the higher rep, slow-twitch fiber training. This will help you to develop all the fibers in your muscles, maximizing your ultimate development.

[tadolfi]

Superb my man!

[Orome]

Excellent post

rep+

[jlbirdwell]

Can different muscles in the body be different? Or are they all the same. Such as if you are a FT in the Bicep, you are a FT in the Glut, Chest, etc.?

[Doug]

Originally Posted by jlbirdwell

Can different muscles in the body be different? Or are they all the same. Such as if you are a FT in the Bicep, you are a FT in the Glut, Chest, etc.?

Yes you can have a difference in different muscles, it is down to your own personal genetic makeup.