BackgroundDuring the crucial stage of the COVID-19 pandemic, face-to-face undergraduate medical education was disrupted and replaced with online teaching activities. Based on its emphasized impact on several outcomes, a deeper insight into the pandemic related effects on medical students´ motivation is aspirational. Therefore, this study aimed to assess the motivational changes that took place during the pandemic in medical students and explored, how motivation of medical students is influenced.MethodsUsing a mixed method inter-cohort study design, 4th year medical students´ motivation, assessed pre- and post-pandemic were compared. In subsequent qualitative analyses underlying variables that may have contributed to both- medical students´ motivation and pandemic related changes were identified. These variables were then systematically explored- both individually and in combination. In a final step, the results were embedded within the Self-Determination Theory.ResultsStudents who were affected by the university lockdown reported significantly higher levels of less self-determined motivation and amotivation. The qualitative analysis identified determinants that influence medical students´ motivation. The common core of these determinants is lacking social interaction and support, with a great emphasis on the interaction with the lecturer and patients.ConclusionThis study emphasizes the crucial role of medical educators, patient contact, social interactions and personal support on students´ motivation. Students need to be strengthened in their beliefs about their abilities, the value of their task at hand and receive encouragement in their efforts. All this will result in an increased identification with the task and less detrimental outcomes.