Background <p>Based on Self-Determination Theory (SDT) and Embodied Cognition Theory (ECT), this study explores how teacher support influences the generation mechanism of psychological well-being in 'language + body' dual-channel teaching through basic psychological needs and learning motivation as a chain mediator.</p> Method <p>The present study adopted an explanatory sequential mixed-methods design, with a quantitative phase as the primary component and a qualitative phase as the supplementary component. The quantitative phase involved a questionnaire survey with 518 university students, analyzed using Structural Equation Modeling (<i>SEM</i>). The qualitative phase consisted of semi-structured interviews with 16 teachers, with the transcripts analyzed via three-level coding.</p> Result <p>(1) Teacher support has a significant positive impact on basic psychological needs (<i>β</i> = 0.416), learning motivation (<i>β</i> = 0.235), and psychological well-being (<i>β</i> = 0.317); (2) Chain mediation: teacher support indirectly and positively affects psychological well-being through basic psychological needs and learning motivation (<i>β</i> = 0.028), with a total mediation effect of 15.47%; (3) Chain effect of embodied interaction: the physical dimension effectively reduces the cognitive load, while the symbolic dimension reinforces the fulfillment of the needs with cultural translations.</p> Conclusion <p>This study extends the SDT-based chain mediation framework by specifying embodied interaction as a contextual instructional condition, and provides an empirically grounded dual-channel pathway for interdisciplinary instructional design.</p>