Comparison of the effects of different swallowing trainings on suprahyoid muscle activation and orofacial muscle thickness

The aim of this study was to investigate the effects of effortful swallow (ES) and masako maneuver (MM) on suprahyoid muscle activation and strength, tongue pressure and orofacial muscle thickness in healthy adults and to compare these swallowing trainings. Thirty-seven volunteers who met the inclusion criteria (aged between18-30 years, scored less than 3 points in the Turkish Eating Assessment Tool) were divided into 3 groups as ES (n=12), MM (n=13) and control group (n=12) by simple randomization. In this experimental study, participants in the ES and MM training groups completed 6 weeks of swallowing training. Participants in both training groups performed a total of 120 swallows in each session, while participants in the control group did not participate in any swallowing training. Participants were evaluated twice, at the beginning of the study and after completion of the 6-week study protocol. Electromyography was used to evaluate suprahyoid muscle activation, digital dynamometer for suprahyoid muscle strength, IOPI (Iowa Oral Pressure Instrument) for tongue pressure, and ultrasonography for suprahyoid muscle thickness. Both trainings did not change suprahyoid muscle activation (p>0.05), but increased suprahyoid muscle strength (p1=0.0001, p2=0.014), increased tongue pressure (p1=0.0001, p2=0.0001), the MM increased the thickness of all evaluated orofacial muscles (p<0.05), and ES increased the thickness of tongue, mhylohyoid (right and left) and digastric muscle (right) (p<0.05) and there was no change in all evaluation parameters in the control group (p>0.05). In addition, ES and MM trainings were found to be similar to each other in terms of improving the evaluated parameters (p>0.05). The results of this study showed that ES and MM trainings are effective in improving suprahyoid and tongue muscle strength and thickness. Considering that suprahyoid muscles and tongue are important in terms of swallowing safety and efficiency, it is thought that both trainings can be promising especially in dysphagic individuals who present with loss of muscle strength and mass.