optimal fiber length and pennation angle change with time

[Frédéric Lamon]

Hello,

I have found that the optimal fiber length is changing according to the activation level of the muscle, which in turn makes the pennation angle at optimal fiber length change as well. I found the relations used to calculate these in an article and I was wondering if there was any way of incorporating this in the Thelen2003 muscle model that I am using ?

relations: lm(t)=lm_0*(gamma*(1-a(t))+1) with gamma = 0.15
alpha(t)=arc sin(lm_0*sin(alpha_0)/lm(t))

Cheers

[jimmy d]

Perhaps link to the article?

[Frédéric Lamon]

Hello James,

Here is the article. It's on page 4. Thanks for looking at it.

Fred