Importance: Physical activity (PA) is a cornerstone in cancer rehabilitation, yet evidence in oral cancer remains limited and heterogeneous, despite the significant functional impairments and morbidity associated with treatment. Objective: This systematic review synthesizes evidence on PA in people living with or beyond oral cancer (PLWBOC), focusing on its association with recovery-related outcomes across the cancer care continuum. Data Sources: A comprehensive systematic search was conducted in 9 databases (PubMed, Embase, CENTRAL, CINAHL, Web of Science, Scopus, PEDro, ClinicalTrials.gov, and the International Clinical Trials Registry Platform [ICTRP]) on October 26, 2024. The review followed PRISMA 2020 and SwiM guidelines and was registered with PROSPERO (CRD42024591662). Study selection: Eligible studies included randomized controlled trials (RCTs), quasi-experimental designs, and observational studies examining the associations between postoperative PA and recovery-related outcomes in PLWBOC. Data extraction and Synthesis: Two reviewers independently extracted data on PA characteristics, outcomes, and study quality using a standardized form. Risk of bias was assessed using the Revised Cochrane Risk of Bias tool for randomized trials (RoB 2) for RCTs and Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) for non-randomized studies, visualized with Risk-Of-Bias VISualization tool (ROBVIS). Twenty-four studies met the inclusion criteria, which encompassed RCTs, pilot trials, and cohort studies. Main Outcomes and Measures: Primary outcomes include physical function, fatigue, health-related quality of life (HRQoL), and treatment-related morbidity. Results: Physical activity consisted of resistance training, aerobic exercise, and multimodal programs combining PA with education or behavioral support. PA was associated with improved functional performance, reduced fatigue, and moderate HRQoL gains. Resistance training increased lean body mass and strength. Early-phase and 12- to 24-week programs showed prominent effects. Supervised, individualized programs yielded higher adherence rates and better functional outcomes. Nonetheless, heterogeneity in protocols, outcome measures, and study quality limited comparability and precluded meta-analysis. Conclusions and Relevance: Physical activity—supervised, multimodal, and early-initiated—offers promising benefits for PLWBOC. Future research should prioritize RCTs, standardized outcome measures, extended follow-up, and digital outreach to establish tailored exercise guidelines for this population.

Background: Patients with head and neck cancer (HNC) are at risk of impaired muscle health due to metabolic disturbances, reduced nutritional intake, and treatment‐related toxicities. Because muscle health supports physical capacity and independence, its decline may affect quality of life (QoL). This systematic review examined the association between muscle health and QoL in patients with HNC. Methods: Studies were included if they involved patients with HNC, used validated muscle health and QoL measures, and examined their association. Risk of bias was assessed using the Quality In Prognosis Studies (QUIPS) tool. Results: Thirteen studies were included. Poorer muscle health was associated with lower global QoL, poorer physical and role functioning, greater fatigue, swallowing difficulties, restricted mouth opening, social eating problems, and salivary toxicities. Methodological limitations and heterogeneity precluded meta‐analysis. Conclusions: Poorer muscle health was associated with worse QoL in patients with HNC, although this evidence does not establish causality. Prospective studies using standardized measures are needed. Trial Registration: PROSPERO Number: CRD42025105208