Background: Shoulder impingement syndrome (SIS) is a prevalent condition among overhead athletes, often managed through therapeutic exercise interventions. However, the quality of reporting in exercise protocols significantly impacts their reproducibility and clinical implementation. The Consensus for Exercise Reporting Template (CERT) provides a standardized framework to assess the quality of exercise reporting in clinical research. Objectives: This systematic review aimed to evaluate the quality of exercise protocols used to treat SIS in overhead athletes by applying the CERT checklist. Additionally, the risk of bias was assessed to determine the methodological rigor of included studies. Methods: A systematic review was conducted following PRISMA guidelines. Six electronic databases (MEDLINE, CINAHL, Sport Discuss, Web of Science, and Cochrane) were searched for eligible studies. Inclusion criteria encompassed randomized controlled trials (RCTs), cohort studies, and case series that investigated exercise therapy for SIS in overhead athletes. Studies had to be published in English and provide details on exercise interventions. Exclusion criteria included non-human studies, acute injuries, and postoperative management. The primary outcome was the quality of intervention reporting, assessed using the CERT checklist. The secondary outcome was the risk of bias, evaluated using the modified Downs and Black checklist. Results: Five studies met the inclusion criteria, comprising four RCTs and one case series. CERT scores ranged from 6 to 13 (median = 8, IQR = 1), indicating suboptimal reporting quality. Commonly reported CERT items included equipment usage and exercise tailoring. However, key aspects such as adherence, motivation, and intervention fidelity were consistently underreported. None of the included studies provided comprehensive details on exercise interventions as per CERT guidelines, limiting their reproducibility and clinical application. Conclusions: The quality of reporting on exercise-based interventions for SIS in overhead athletes remains insufficient. Critical gaps in adherence monitoring, patient motivation, and intervention fidelity were identified. Future research should prioritize standardized and detailed reporting of exercise interventions to enhance reproducibility and facilitate evidence-based clinical practice.