The effects of neuromuscular joint facilitation treatment using neck patterns on the acoustic analysis of swallowing sounds in healthy adults

[Purpose] We aimed to investigate the changes in the swallowing sounds of healthy adults during neuromuscular joint facilitation treatment using neck patterns. [Participants and Methods] A total of 20 healthy adults (10 males and 10 females; mean age, 29.2 ± 6.3 years) swallowed 10 mL of water four times under three conditions (after the neuromuscular joint facilitation neck-flexion resistance pattern, after the Shaker-type exercise, and during relaxed sitting without prior exercise [control]), randomly ordered with an interval greater than 3 days. Swallowing sounds for each water swallow were recorded using cervical auscultation. [Results] The mean amplitude of swallowing sound intensity and the mean spectral frequency were significantly higher after the neuromuscular joint facilitation neck-flexion resistance pattern and the Shaker-type exercise, in comparison with those in the control group. [Conclusion] Neuromuscular joint facilitation training with the neck-flexion resistance pattern influenced swallowing sounds to the same degree as the Shaker-type exercise, implying that this resistance pattern may enhance suprahyoid muscle contraction.