Effects of a Thermoformable Mouthguard on Cervical Posture and Running Performance in Non-professional Runners

Inclusion criteria: * Students from Universidad Europea de Valencia enrolled in dentistry and physiotherapy programs, aged between 18 and 25 years * Regularly engaged in running training, with at least one year of experience * Already participated in an official half marathon * Good general health status * Willingness to comply with the study protocol and provision of written informed consent prior to participation Exclusion criteria: * Subjects reporting a history of muscular injuries, active inflammatory or infectious processes in the last 6 months * Known cardiovascular diseases * Pregnancy * Use of orthopedic shoe insoles * Use of mouthguard during running As I am unable to upload the flow chart image, I have provided its content in text format below. 1. Recruitment * Participants assessed for eligibility (n = 17) * Excluded (n = 8): * Declined participation due to lack of time (n = 3) * Did not meet the inclusion criteria (n = 5) 2. Allocation and follow-up * Participants included in the study (n = 9) * Assigned to both conditions (within-subject design): * Natural occlusion condition (n = 9) * Thermoformable mouthguard condition (n = 9) * Completed follow-up (n = 9) 3. Analysis - Participants included in the final analysis (n = 9)