Study protocol for a randomized controlled trial: tongue strengthening exercises in head and neck cancer patients, does exercise load matter?
BACKGROUND
Reduced tongue strength is an important factor contributing to early and late dysphagia in head and neck cancer patients previously treated with chemoradiotherapy. The evidence is growing that tongue strengthening exercises can improve tongue strength and swallowing function in both healthy and dysphagic subjects. However, little is known about the impact of specific features of an exercise protocol for tongue strength on the actual outcome (strength or swallowing function). Previous research originating in the fields of sports medicine and physical rehabilitation shows that the degree of exercise load is an influential factor for increasing muscle strength in the limb skeletal muscles. Since the tongue is considered a muscular hydrostat, it remains to be proven whether the same concepts will apply.


METHODS
This ongoing randomized controlled trial in chemoradiotherapy-treated patients with head and neck cancer investigates the effect of three tongue strengthening exercise protocols, with different degrees of exercise load, on tongue strength and swallowing. At enrollment, 51 patients whose dysphagia is primarily related to reduced tongue strength are randomly assigned to a training schedule of 60, 80, or 100% of their maximal tongue strength. Patients are treated three times a week for 8 weeks, executing 120 repetitions of the assigned exercise once per training day. Exercise load is progressively adjusted every 2 weeks. Patients are evaluated before, during and after treatment by means of tongue strength measurements, fiber-optic endoscopic evaluation of swallowing and quality-of-life questionnaires.


CONCLUSIONS
This randomized controlled trial is the first to systematically investigate the effect of different exercise loads in tongue strengthening exercise protocols. The results will allow the development of more efficacious protocols.


BACKGROUND
Current Controlled Trials ISRCTN14447678.
Department of Otolaryngology and Head & Neck Surgery - Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium. Gwen.van.nuffelen@uza.be.|Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium. Gwen.van.nuffelen@uza.be.
Gwen
G
Van Nuffelen
Department of Otolaryngology and Head & Neck Surgery - Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium. Leen.VandenSteen@uza.be.
Leen
L
Van den Steen
Department of Otolaryngology and Head & Neck Surgery - Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium. Olivier.vanderveken@uza.be.|Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium. Olivier.vanderveken@uza.be.
Olivier
O
Vanderveken
Department Medical Oncology, Antwerp University Hospital, Antwerp, Belgium. Pol.specenier@uza.be.
Pol
P
Specenier
Department of Otolaryngology and Head & Neck Surgery - Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium. Carl.Vanlaer@uza.be.
Carl
C
Van Laer
Department of Otolaryngology and Head & Neck Surgery - Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium. Diane.Vanrompaey@uza.be.
Diane
D
Van Rompaey
Department of Otolaryngology and Head & Neck Surgery - Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium. Cindy.Guns@uza.be.
Cindy
C
Guns
Department of Otolaryngology and Head & Neck Surgery - Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium. Steven.marien@uza.be.
Steven
S
Mariën
Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium. Marc.Peeters@uza.be.|Department Medical Oncology, Antwerp University Hospital, Antwerp, Belgium. Marc.Peeters@uza.be.
Marc
M
Peeters
Department of Otolaryngology and Head & Neck Surgery - Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium. Paul.van.de.heyning@uza.be.|Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium. Paul.van.de.heyning@uza.be.
Paul
P
Van de Heyning
University College Thomas More, Antwerp, Belgium. janvanderwegen@telenet.be.|Department of Otolaryngology and Head & Neck Surgery, UMC Sint-Pieter, Brussels, Belgium. janvanderwegen@telenet.be.
Jan
J
Vanderwegen
Department of Otolaryngology and Head & Neck Surgery - Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium. Marc.de.bodt@uza.be.|Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium. Marc.de.bodt@uza.be.|Faculty of Speech, Pathology and Audiology, Ghent University, Ghent, Belgium. Marc.de.bodt@uza.be.
Marc
M
De Bodt
D001530:Belgium; D059248:Chemoradiotherapy / Q000009:adverse effects*; D002985:Clinical Protocols; D003679:Deglutition; D003680:Deglutition Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D005081:Exercise Therapy / Q000379:methods*; D005336:Fiber Optic Technology; D006258:Head and Neck Neoplasms / Q000175:diagnosis / Q000628:therapy*; D006801:Humans; D007828:Laryngoscopy; D053580:Muscle Strength; D020127:Recovery of Function; D012107:Research Design; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013997:Time Factors; D014059:Tongue / Q000503:physiopathology*; D016896:Treatment Outcome