It is unclear if skeletal muscles act mechanically as independent actuators. The purpose of the present study was to investigate force transmission from soleus (SO) muscle for physiological lengths and relative positions in the intact cat hindlimb. We hypothesized that force transmission from SO will be affected by length changes of its two-joint synergists. Ankle plantar flexor moment upon excitation of SO was measured for various knee angles (70-140°). This involved substantial length changes of gastrocnemius and plantaris. Ankle angle was kept constant (80°-90°). However, SO ankle moment was not significantly affected by changes in knee angle, neither were half-relaxation time and maximal rate of relaxation (p>0.05). Following tenotomy, SO ankle moment decreased substantially (55 ± 16%) but did not reach zero, indicating force transmission via connective tissues to the Achilles tendon (epimuscular myofascial force transmission). During contraction SO muscle shortened to a much greater extent than in the intact case (16.0 ± 0.6 mm vs. 1.0 ± 0.1 mm), which resulted in a major position shift relative to its synergists. If SO was moved back to its position corresponding to the intact condition, SO ankle moment approached zero and most muscle force was exerted at the distal tendon. Our results also suggested that in vivo the lumped intact tissues linking SO to its synergists are slack or are operating on the toe region of the stress-strain curve. Thus, within the experimental conditions of the present study, the intact cat soleus muscle appears to act mechanically as an independent actuator.