Fiber-Type Proportions of Third Parasternal Intercostal Muscles
The third parasternal intercostal muscle contained a majority of fast type IIx/b afibers (Figure 2).
Morphological Assessment of Third Parasternal Intercostal Muscles
The majority of the parasternal intercostal muscle fibers were normal fibers that occupied a significantly larger [A.sub.A] than connective tissue or remodeling fibers (p < 0.001).
The current study measured the CSA and myogenic remodeling responses of parasternal inspiratory intercostal muscles following brief, intense pressure overload training.
While similar hypertrophic responses were detected in both the diaphragm and parasternal intercostal muscles, only the parasternals contained an increased prevalence of slow fibers and eMHC fiber expression.
We stimulated only two intercostal muscles from each hemithorax, while DiMarco et al.
This limitation was generally identified during autopsy to be caused by dislodgement of the intramuscular electrodes from their implantation site in the intercostal muscles as they had migrated to the latissimus and serratus muscles (Figure 2).
In addition, intercostal muscles include both the external and internal muscles.
Thus, stimulating along the lower thoracic ribs closer to the origin of intercostal nerves may increase abdominal muscle responses.
Including intercostal spaces two through five would be expected to have a positive effect.
Intercostal muscle stimulation was limited by coactivation of the serratus and latissimus muscles as well as by displacement of the electrodes.