The effects of opposite-directional static contraction of the muscles of the right upper extremity on the ipsilateral right soleus H-reflex.

The objective of this study was to explore the neurophysiological remote after-effects of resistive static contraction (SC) of the muscles of the upper extremity, considering the resistant direction on the ipsilateral (right) soleus H-reflex. The participants included 12 normal subjects with a mean (SD) age of 23.8 (2.8) years. The subjects were asked to maintain their upper extremity against the traction force, at a level of resistance that was 50% of the maximal SC strength. A 20-s SC of the muscles of the upper extremity utilizing contraction of the upper extremity muscles using a diagonal flexion (shoulder flexion-adduction-external rotation) or extension (shoulder extension-abduction-internal rotation), a proprioceptive neuromuscular facilitation (PNF) pattern was induced. The traction force line of the diagonal flexion or extension direction ran parallel to the diagonal line from the left acromion process to the right ASIS. Three-way analysis of variance of the H/Mmax ratio with Scheffé's post-hoc tests revealed that the H/Mmacorrelatex ratio of SC via diagonal extension was significantly smaller than that via diagonal flexion and that the H/Mmax ratio during the 120-140 s phase after SC, as remote after-effect SC, was significantly smaller than that during SC. The induction of neurophysiological descending effects for inhibition requires consideration of the force direction.

Comparison of the effects of remote after-effects of static contractions for different upper-extremity positions and pinch-force strengths in patients with restricted wrist flexion range of motion.

The objective of the study was to examine the after-effects of static contractions of upper extremity muscles in different shoulder joint positions and at different pinch-force strengths on the maximal active range of motion (MAROM) and wrist agonist/antagonist IEMG activities for patients with restricted wrist flexion range of motion (ROM) due to upper limb pain and dysfunction. The subjects were 10 outpatients (3 males, 7 females) with restricted wrist joints. These subjects performed four static contractions of upper extremity muscles in neutral and diagonal shoulder joint positions and with weak and strong pinch-force strengths in random order. Two-way repeated measures analysis of variance showed that the change in MAROM was significantly larger (P < 0.05) after diagonal-strong static contractions than after neutral-weak static contractions. There were no significant correlations between changes in MAROM and IEMG activities. These results indicate that shoulder joint position and pinch-force strength should be considered for effective induction of remote after-effects of static contractions for increasing MAROM for restricted wrist flexion ROM.

Effect of remote after-effects of resistive static contraction of the pelvic depressors on improvement of restricted wrist flexion range of motion in patients with restricted wrist flexion range of motion.

The objective of the study was to compare the effects of remote after-effects of resistive static contraction of the pelvic depressors (RSCPD) with after-effects of static contraction of upper extremity muscles (SCUE) on improvement of the maximal active range of motion (MAROM) for patients with restricted wrist flexion range of motion (ROM) due to upper limb pain and dysfunction. The participants were 10 outpatients with restricted wrist joints. The mean (SD) age was 53.7 (4.4) years (range, 34-81). The subjects performed two exercise protocols (SCUE and RSCPD) in random order. One-way repeated measures ANOVA showed significant main effects in evaluation of the change in MAROM and IEMG activities for different conditions (after rest, after SCUE, and after RSCPD). The remote after-effects of RSCPD, but not those of SCUE, caused significant improvement in MAROM for restricted wrist flexion ROM.