Changes in H-Reflex Amplitude During Massage of Triceps Surae in Healthy Subjects

Abstract

The purpose of this study was to investigate the effects of massage on neuromuscular excitability, as measured by changes in Hoffmann reflex (H-reflex) amplitudes. Nine healthy subjects (= 25.2 years; 2 males, 7 females), with no history of neurological disease, participated in the study. H-reflexes were elicited from the right soleus muscle by delivering square wave impulses (Grass S48 stimulator) of 1 msec duration to the posterior tibial nerve of the same leg. H-reflex peak to peak amplitudes were measured at 10 sec intervals, and a total of 10 recordings were made during each of five separate conditions (C1, C2, MASS, C3, and C4). Two pretreatment control (C1 and C2) conditions, separated by a 5-minute pause in the recordings, were immediately followed by the massage condition (MASS). H-reflex recordings were also made during the first 2 minutes of a 3-minute massage application to the right triceps surae muscle group. One post-treatment control (C3) condition was introduced immediately following the termination of the massage, and a second (C4) after a 5 minute delay. A one-way repeated measures analysis of variance revealed a significant difference among conditions (F4,32 = 32.26, p < 0.01) for individual means. Newman Keuls post hoc procedures for pair-wise comparisons revealed that all massage-control pairings were statistically different (p < 0.01). No other pairings (control-control) were significantly different. A 71% decrease in H-reflex amplitudes was observed during the massage, followed by a return to baseline levels immediately following the termination of the massage. These results suggest the use of massage as an alternative to other therapeutic modalities such as passive muscle stretching and tendon pressure to decrease spinal motoneuron excitability. J Orthop Sports Phys Ther 1990;12(2):55-59.