Table 4.

Ways that intensity of swallowing exercises was reported or varied in studies

Swallowing exercise	Different ways intensity was reported or varied
Chin tuck against resistance (CTAR)	Verbal description, e.g., “as far as possible” [31], “as strongly as possible” [52] Use of external resistance, e.g., device [52, 71], resistance bar [72], ball [31] Game-based feedback at certain percentage of 1-RM [72]
Effortful swallowing	Verbal description, e.g., “as hard as possible” [73], “as forcefully as possible” [62]
EMST/breathing exercises	Expiratory pressure set on device [50, 64, 65, 67] Verbal description, e.g., “deep and forceful breaths” “fast and forcefully”
Jaw opening	Against external resistance (e.g., ball, device) [54, 58, 74] Against trainer’s hand at set percentage of maximum voluntary contraction using sEMG feedback [66] Verbal description, e.g., to “maximum extent” [35]
Lip exercises	Gradually increasing external resistance, e.g., pulling force on oral screen [75], oral device [59] Percentage of maximum pressure with IOPI [76]
Mendelsohn	Increasing length of laryngeal excursion [36] Use of sEMG feedback [78] Verbal description, e.g., swallow “long and strong” [78]
PNF-based exercises	Tester providing resistance in opposite direction to jaw or neck movement [79]
Swallowing	Percentage of maximum pressure and different lengths of swallow hold using game-based biofeedback [28] Against resistance from kinesiology taping [60] Gradually increasing amount of food to be swallowed [57]
Tongue strengthening	Percentage of maximum pressure with IOPI or MOST, ranging from 60% to 80% [27, 49, 51, 68, 69] Verbal description, e.g., “press strongly” [62] or “as hard as possible” against roof of mouth [29]
Therapeutic programs	Use of external resistance, e.g., external force pushing in opposite direction [56, 82] Increasing training target goals, repetitions, or duration [33] Move from passive to active exercise and/or increasing amount of activity [57] Verbal description, e.g., “as much as possible” [39], “very hard” [34, 44]

1-RM 1-repetition maximum, CTAR chin tuck against resistance, EMST expiratory muscle strength training, IOPI Iowa Oral Performance Instrument, MOST Madison Oral Strengthening Therapeutic device, PNF Proprioceptive Neuromuscular Facilitation, sEMG surface electromyography