<![CDATA[Background: Bruxism is a centrally regulated masticatory muscle behavior expressed during sleep or wakefulness and influenced by biological, psychological, behavioral, and environmental factors. Physical activity is biologically plausible as a rehabilitation strategy because it can reduce psychological distress, improve sleep, enhance physical function, and support self-regulation. However, direct reduction of bruxism by exercise has not been established. Purpose: To synthesize evidence on whether physical activity and exercise may reduce bruxism directly or indirectly, while distinguishing recreational activity from high-load competitive sport and distinguishing bruxism frequency from bruxism-related pain and functional consequences. Method: A structured narrative review was conducted using PubMed and supplementary publisher and bibliographic searches, with literature updated through August 6, 2026. Evidence was prioritized from randomized clinical trials, observational studies, systematic reviews, and international consensus statements. Direct bruxism outcomes were distinguished from indirect outcomes including stress, sleep, pain, function, and quality of life. Results: The evidence indicates three main patterns. First, randomized trials of home exercise in people with bruxism reported improvements in stress, sleep, pain, quality of life, and bruxism-related questionnaire outcomes, while objective reductions in bruxism activity were not consistently established. Second, masticatory muscle stretching alone did not reduce sleep bruxism and increased bruxism bursts in one randomized trial. Third, athlete studies indicate that sport participation does not inherently protect against bruxism; psychosocial and training demands may be associated with greater vulnerability in some populations. Conclusion: Physical activity is best positioned as an individualized rehabilitation adjunct rather than a proven direct anti-bruxism treatment. Its potential benefit is likely to depend on exercise dose, recovery, sleep, stress, pain, functional impairment, and sport context. Future prospective studies should combine objective bruxism measures with detailed exercise and psychosocial exposure assessment. Keywords: Bruxism; Exercise Therapy; Physical Activity; Rehabilitation; Stress. ]]>
