muscles part and activation

Main Forum
1

Hello
In ANYBODY program, a muscle like transversus has 5 part, trapezius has 6 part and other muscles too. when i run the model to report results, I want to report transversus muscle force as “1” muscle not “5” , how do this?
and
I have muscle forces as results; if i want to have muscle activation, exist any way (formula or…) for converting force to activation out of software? or i should start running again ?
Thanks
Mehrdad

2

Hi

This could be done in different ways…
One way would be to write something like


AnyVar ModelEnvelope = max({ Main.Model.HumanModel.Right.Leg.Mus.GluteusMedius1.Activity,
      Main.Model.HumanModel.Right.Leg.Mus.GluteusMedius2.Activity,
      Main.Model.HumanModel.Right.Leg.Mus.GluteusMedius3.Activity});

This would give you the activity envelope of these two muscles…
See the file in AMMR beta/Validation/GaitVaughan/Model/EMGComparison.any for more details,

It could also be that you would like to use the sum instead…

You will need to rerun the models or do it outside AnyBody

Best regards
Søren

3

Hi
thank you Søren for reply,
but I have another question, this code give me maximum activation between 5 or 6 part of a muscle at a moment? i want a code considering all the part.
I think, average of these parts based on PCSA of that fiber is the answer.
(sum of (activation of part* PCSA of part in software))/(PCSA of muscle in literature)
what’s your opinion?

and activation=force/MVC, in AnyBody: MVC=F0*PCSA? it’s means, I can covert the muscle force to activation outside AnyBody?

Best Regards
Mehrdad

4

Hi Mehrdad,

I think you suggestion sounds resonable it will weight the activations from the individual parts considering their PCSA, but i would consider to use a average instead of sum for this, so use your formula but have average instead of sum.

In AnyBody activation is foudn as Activation = Actual force in muscle/ Strength (N)

Best regards
Søren

5

Hi Søren,
Thank you very much for your help.
Best regards
Mehrdad