Specifications

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Try running the InverseDynamicAnalysis again and plot the Activity of Muscle2. You should see the
following:
As you can see, this is again very different from what we have seen before. Plotting the strength will reveal
what has happened:
What the MuscleCalibrationAnalysis does is to run through the specified movement and compute the
variation of the origin-insertion length of the muscle. It subsequently changes the user-defined value of Lt0
such that the length of the contractile element equals the optimum fiber length, Lm0, when the origin-
insertion length is at its mean value. Notice that this does not necessarily correspond to the length when
50% of the movement has passed.
The rationale behind this method of tendon length calibration is that if you analyze a movement that is
representative for what the body is created to do, then the muscles should probably attain their optimum
fiber lengths somewhere safely within the interval of movement. Naturally this is not a very accurate way of
doing it, and it will not work if you are modeling a movement that is outside the typical posture of the joints
in the model.
Please notice that the tendon lengths specified in the AnyScript model are not altered by this method. Every
time you reload the model you must run the MuscleCalibrationAnalysis again.