Figure 4

Example 2: Longitudinal and transversal captures. The first (a) and second (c) score vectors are plotted along with the orthogonal component (b). The movement has three phases: An active dynamic concentric phase (during muscle activation), an active static contraction phase (when the muscle is constantly tense) and a passive eccentric phase (when the arm returns to the baseline position). The active dynamic concentric phase has two sub-phases, Phase 1 and Phase 2. In Phase 1, it is mainly the Musculus biceps brachii caput breve and Musculus brachialis that are active (see Figures (d) and (e)); and in Phase 2 it is mainly the Musculus biceps brachii caput longum that is active (see Figures (f) and (g)). This is seen in Figure (a) as a plateau starting at the end of Phase 1 and at the beginning of Phase 2, and as a local maximum in Figure (b). In Phase 3 there is a small twitch in the longitudinal capture that is captured clearly in the orthogonal component, Figure (b). Phase 4 is the end of the movement, the passive eccentric phase when the muscle returns to rest.