Effects of Lingual Endurance Exercise on Rehabilitation of Swallowing Impairment After Ischemic Stroke
Phase: NA
Conditions: Dysphagia, Oral Phase, Stroke, Ischemic
Sponsor: University of Cincinnati

Lingual Endurance Exercise in Treating Post-Stroke Dysphagia 
NCT05523973 
Last Institutional Review Board Approval Date: 2/18/25 
 
 
 
 

Study Protocol 
All procedures and study team members were approved by University of Cincinnati Institutional Review 
Board (IRB# 2022-0218). A convenience sample of participants were recruited from word-of-mouth 
referrals (e.g. UC stroke team) and information flyers that were distributed locally throughout the 
community and at other institutions in the area. Participants were eligible to participate if they had  a 
history of ischemic stroke, were 21 years of age or older, at least 3 months since initial ischemic stroke, 
and able to follow 2 step directions. Exclusion included any history of dysphagia prior to the ischemic 
stroke, if participant was pregnant, or had a history of temporomandibular joint disorders. Final eligibility 
for full protocol enrollment included at least one impaired oral component score according to the 
MBSImP (Modified Barium Swallow Impairment Profile). This was judged at time of initial visit in the 
fluoroscopy suite by an MBSImP trained speech language pathologist (SLP).  
Study Visits 
This study used a prospective quasi-experimental design, with pre-test and post-test measures. Study 
visits included an initial in-person baseline visit with patient reported outcome measures (Swallowing 
Quality of Life Questionnaire, SWAL-QoL, and Eating Assessment Tool, EAT-10) and a modified barium 
swallow study (MBSS) followed by 8-10 weeks of at home lingual exercise with use of the 
TongueometerTM device. Weekly virtual visits completed with a license speech language pathologist. At 
the end of the 8-10 weeks participants came for an in person visit for post-treatment data collection.  
Participants were asked to complete lingual presses based on 75% repetitions at 50% of their maximum 
isotonic press. Participants were assigned to complete this task 3 times per day. Half of the participants 
were instructed to complete this task 2 times a day and once a day to do 10 effortful swallows with 
feedback from the device. Post-treatment data were collected at a final study visit where the same PROs 
were administered (SWAL-QoL, EAT-10) along with a post-treatment MBSS. Procedural details for study 
visits and exercises described below:  
Modified Barium Swallow Study 
 A standard MBSImP protocol was utilized under videofluoroscopy using Varibar Barium products 
(Varibar® E-Z-EM, Inc. 40% w/v ratio. This includes 12 bolus trials including: thin 
(International Dysphagia Diet Standardization Initiative, IDDSI 0), mildly thick (IDDSI 2), 
moderately thick (IDDSI 3), and Varibar pudding (IDDSI 4+), and a solid (cookie) with 5ml 
Varibar pudding.  
Lingual Pressure Measures 
Two lingual manometers were used for data collection at the pretreatment and post treatment 
visits. Collected with the Iowa Oral Performance Instrument (IOPI), the following measures were 
recorded (in repetitions, time, or kP) in the anterior position: swallow pressure x3 (saliva swallow), 
effortful swallow x3 (swallow with focus on muscle contraction and tongue pressing to the roof of the 
mouth), maximum isotonic pressure (MIP) x3 (press as hard as able and release), isometric endurance 
(ISO-M) x1 (press and hold at 50% of the highest MIP). Posterior lingual measures with IOPI were 
measured: MIP x3, ISOM, isotonic endurance maximum (ISO-T) (press and release as many times until 
fatigued to reach 50% of posterior MIP) . The TongueometerTM  device, was sent home with the 
participants for their at home exercise. To determine lingual exercise, baseline TongueometerTM 
measurement included anterior ISO-T. Participant were prescribed 75% anterior lingual presses at 50% of 

their max MIP. For example: if patients’ max MIP was 50 kPa and max ISO-T was 100 presses. 
Participant would be asked to complete 75 presses with force at least 25 kPa.  
Adherence Monitoring 
TongueometerTM device allows for virtual reports of adherence data and exercise parameters (pressure 
settings) to be sent securely to study team. Participants met with SLP virtually every week. Every two 
weeks participants Max MIP x3 and new ISO-T was measured updated number or repetitions, and max 
press was provided.  
MBSS Data Analysis 
Each pre and post MBS was rated by two license speech language pathologist for MBSImP, , and 
pixel based and timing measures following the Analysis of Swallowing Events, Physiology, and 
Timing (ASPEKT) method. If discrepancies were noted, they were resolved during consensus 
meetings.  
Statistical analysis 
Descriptive statistics were calculated on all variables. Frequencies and percentages are reported 
for categorical variables. The normality of  continuous variable distributions were assessed using 
histograms and box plots. For normally distributed continuous variables, means and standard 
deviations are reported, while . medians and interquartile ranges are provided for non-normally 
distributed continuous variables. 
 To examine treatment effects, differences in baseline measures from pre-treatment to post 
treatment were calculated, including EAT-10 scores; IOPI measures: average swallow pressure 
(kPa) over 3 trials, maximum effortful pressure (kPa) over 3 trials, maximum anterior max 
strength (kPa) over 3 trials, anterior isometric endurance max (seconds), and maximum anterior 
isotonic endurance (reps); maximum posterior strength (kPa) over 3 trials, posterior isometric 
endurance max (seconds), posterior isotonic endurance max (reps); MBSImP Oral Total scores, 
MBSImP Pharyngeal Total scores; and Swallowing Quality of Life questionnaire scores (SWAL-
QOL), including overall total score, eating duration, food selection, fear, and fatigue; and 
ASPEKT measures, including Swallow reaction time, Pharyngeal swallow duration, UES 
opening, Laryngeal vestibular closure reaction time, Laryngeal vestibular closure duration, Pre-
swallow residue, Vallecular residue, Pyriform sinus residue, Other residue, Pharyngeal area at 
max constriction, Maximum opening of UES, and Peak hyoid movement. 
 Linear regression models were used to examine differences in baseline measures from pre-
treatment to post treatment. Treatment group (Endurance only vs Endurance plus transference) 
and baseline measures were included as covariates. Models were evaluated for parsimony. 
Treatment group effects that were not statistically significant were eliminated from the model 
and re-evaluated. Residuals were examined to assess model fit. Bowker’s test of symmetry was 
used to test for differences in PAS score category and FOIS from pre- to post-treatment. Cohen’s 
d was used to calculate effect sizes. Statistical significance was determined at p-values less than 
0.05. All analyses were conducted using SAS version 9.4 (SAS Institute, Cary, NC).