Effects of massage on alpha motoneuron excitability

Although massage has been used as a therapeutic technique by physical therapists for a long time, substantiation of its effects of muscle relaxation and a scientific basis for this reputed effect have been lacking. Recent research has suggested that petrissage (kneading massage) of muscles inhibits the activity of the muscle's spinal motoneurons. These nerves maintain a consistent muscle length by causing muscle contraction after the muscle has been stretched. Other techniques such as tendon pressure or tapping on muscles have also been found to reduced motoneuron excitability, thus causing a decrease in muscle tension. However, another study suggests that muscle tapping can result in a more generalized response of the neuromuscular system, not confined only to the muscle being tapped or manipulated. To better understand the effects of massage on the neuromuscular system, 16 subjects (eight female) were massaged on four sites on the legs. As in most studies of this type, changes in H-reflex amplitude, an indirect measure of motoneuron excitability, were monitored by study of electrical signals in muscles. Gender had no effect on responses. As with other techniques for stretching muscles, petrissage caused a decreased in motoneuron activity in the massaged muscle. Inhibition of the muscle in the calf was not observed when massage was given in the thigh or on two areas on the other leg. The study indicates that massage reduces muscle reflex activity specifically in the muscle being massaged. The applicability of these findings to neurologically impaired subjects needs further evaluation. (Consumer Summary produced by Reliance Medical Information, Inc.)
The purpose of this study was to investigate the specificity of the effects of message (petrissage) on spinal motoneuron excitability as measured by changes in the peak-to-peak amplitude of H-reflex recordings. H-reflexes (and M-responses) were recorded from the distal aspects of the right triceps surae muscle of 8 men and 8 women, aged 20 to 37 years, with no neuromuscular impairments of the lower extremities. The H-reflexes were recorded during five control and four experimental conditions (20 trials at each condition). The control conditions (C1-C5) preceded and followed each experimental condition, providing a measure of the stability of the H-reflex. Each experimental condition consisted of a 4-minute period of massage of the ipsilateral and contralateral triceps surae and hamstring muscle groups (ITS, CTS, IHS, and CHS, respectively). The mean peak-to-peak amplitude of the H-reflex was found to be stable (range=1.91-1.85 mV) across the five control conditions. H-reflex amplitudes recorded during the experimental conditions indicate that massage of the ITS resulted in a reduction of the H-reflex (0.83 mV) in comparison with the pretest control condition (C1) and the remaining experimental conditions (range=1.77-2.23 mV). This difference was significant, and subsequent Newman-Keuls tests indicated a specificity of the effects of massage on the muscle group being messaged. [Sullivan SJ, Williams LRT, Seaborne DE, Morelli M. Effects of message on alpha motoneuron excitability. Phys Ther. 1991; 71:555-560.]
Massage is one of the oldest therapeutic modalities available to physical therapists. [1,2] Although therapists frequently report empirical changes in the reflex activity of muscles resulting from message, there is [...]