Hello
I was going through the paper by Darryl G. Thelen (Adjustment of Muscle Mechanics Model Parameters to simulate Dynamic Contractions in Older Adults 2003) and I noticed that muscle activation and EMG are different. Is it applicable to Opensim also?
Thank you
What is the difference between muscle activation and EMG?
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Thomas Uchida
- Posts: 1784
- Joined: Wed May 16, 2012 11:40 am
Re: What is the difference between muscle activation and EMG?
Yes. See, for example, Fig 2 in Hamner and Delp (2013) and the description thereof (Section 2.2, paragraph 2).muscle activation and EMG are different. Is it applicable to Opensim also?
Hamner, S.R., Delp, S.L. (2013) Muscle contributions to fore-aft and vertical body mass center accelerations over a range of running speeds. Journal of Biomechanics 46:780–787. http://nmbl.stanford.edu/publications/p ... er2012.pdf
Re: What is the difference between muscle activation and EMG?
How can I compare Activation to EMG or can I convert Activation to EMG?
Thank you
Thank you
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Thomas Uchida
- Posts: 1784
- Joined: Wed May 16, 2012 11:40 am
Re: What is the difference between muscle activation and EMG?
Even after rectifying, filtering, and normalizing, EMG will still differ from activation because of the time delay between excitation and force generation. You could shift EMG in time, or report as it is and recognize that the delay between EMG and activation is expected. I recommend reading the literature to see how this has been approached.How can I compare Activation to EMG or can I convert Activation to EMG?