Movie 3.

Example of a low-TCS walking bout with the respective footfall pattern and visualization of PCs 1 and 3. Footfall pattern: black indicates swing phase, white indicates stance phase. Video view: tracked leg tips (round markers) with parts of their prospective movements for clarity. Open markers indicate swing phase, filled markers indicate stance phase. Note that the walking speed is similar to that in Movie M2. Movie M3 shows relatively low TCS values, associated with increased amplitudes in direction of PC 3 and simultaneously decreased PC 1 activity. Unlike to the example in Movie M2, the differentiation of swing and stance activity of individual legs or tripod groups in the subspace spanned by PC 1 and 3 is not directly possible for low TCS examples, as the activity of individual legs does not align with the score time courses as during more tripod-like coordination.