Figure 6. Simultaneous recordings of wrist extensor IEMG activity and wrist flexor tension responses during active repetitive wrist dorsiflexions.

Dashed lines show tension base line (defined as in Fig. 5A) and resting wrist position (defined as in Fig. 1). Note the close correspondence between the strength of the short-range stiffness as exhibited by the flexor tension responses and the strength of the initial extensor activation required for movement generation.