Pulse Width Measurement for measuring muscle activation

[Larry To]

Hi all,

I am conducting a long-term EMG study on unimpaired individuals. I am currently having a hard time counting individuals' activation. I am wishing to measure the onset of an activation and the duration of the activation. I am wondering if any one of you have any suggestion on how to do so. I also have accelerator data but I am not sure how to use it.

Thanks guys.

[Edmund Cramp]

Re: Pulse Width Measurement for measuring muscle activation

I think that the general approach to this type of measurement would be to use the physical activity information - in your case from the accelerometer - to define a period of EMG activity to analyze. So look at the accelerometer data, figure out if it describes a motion that you are interested in, and then analyze the EMG activity from that period. Naturally, for this to work, you will need the EMG and accelerometer data to be synchronized.

Good Luck!

[Larry To]

Re: Pulse Width Measurement for measuring muscle activation

Yes they are synchronized, but accelerometer cannot detect isometric contraction.

[Edmund Cramp]

Re: Pulse Width Measurement for measuring muscle activation

Then add a sensor that will give you the timing information that will tell you when the event that you are interested in occurs.

[Dan Robbins]

Re: Pulse Width Measurement for measuring muscle activation

Hi Larry,

In terms of response to movement, the advice Edmund has given you is great. If you are more interested in muscle activity which occurs to prevent movement, i.e. where you get no data from your accelerometer, you will need to use a threshold detection algorithm, for example a multiple of baseline activity.

Regards
Dan