Fig. 4.

(A) Ratio of tendon rest length to muscle fascicle length in pelvic and thoracic limb muscles. A vertical broken line separates pelvic limb MTUs from thoracic limb MTUs. Pelvic limb abbreviations follow those given in Tables 1 and 2. Pelvic and thoracic limb muscles with the same name are distinguished by the suffixes _P and _T, respectively. Thoracic limb abbreviations are as follows: FCU (flexor carpi ulnaris); FCR (flexor carpi radialis); UL (ulnaris lateralis); SDF_T (flexor digitorum superficialis); DDFH (humeral head of flexor digitorum profundus); DDFR (radial head of flexor digitorum profundus); DDFU (ulna head of flexor digitorum profundus); EDLA_T (extensor digitorum lateralis); EDC (extensor digitorum communis), ECR (extensor carpi radialis). Thoracic limb muscle tendon unit data are from Brown et al. (2003a). In order that muscle tendons with smaller TRL : MFL ratios can be seen, the y-axis is restricted to 70 and the value for SDF_P is given at the top of the column. (B)Ratio of estimated tendon stretch when the muscle exerts its maximum isometric force to mean muscle fascicle length in pelvic limb muscles. Mean muscle fascicle lengths were taken directly from Table 4. For those muscles with several bellies but a single tendon of insertion (i.e. biceps femoris and gastrocnemius), mean fascicle length was weighted according to muscle belly mass following the methods of Alexander et al. (1981).