(A) Sketch of the implemented elbow moment arm model with (B) example data of subject 0.

(A) Schematic depiction of the applied biomechanical model of muscle and tendon in the elbow joint. kT1 and kT2 are non linear spring elements representing the lower and upper biceps brachii tendons. The shoulder and lower arm insertions are also marked ( and ). These points were determined based on anatomic landmarks as formulated in Eq (37). The elbow joint was abstracted as revolute joint. It was located at . The effective lever length of subject 0 is shown in (B) over the elbow joint angle Θ. The maximal effective lever length is marked at (Θ = 93.3∘, leff = 5.2cm).