Digital education is a core direction for the reform of higher physical education. Generative artificial intelligence (GenAI) provides a new technological paradigm to innovate university physical education teaching and improve teaching quality. Based on literature review, questionnaire survey, expert interview and logical analysis, this study takes teachers and students from 30 domestic undergraduate universities as samples to explore the value, dilemmas and mechanisms of GenAI application, and constructs targeted implementation paths. GenAI boosts teaching development in four dimensions, effectively solving problems such as homogeneous instruction, insufficient process evaluation and lack of personalized teaching. Currently, the integration of GenAI and physical education is hindered by teachers' inadequate digital literacy, poor technology scenario adaptation, incomplete data security management and absent ethical norms. These issues result from insufficient digital investment, backward teacher training, imperfect institutions and lagging specialized technological research. This paper proposes an integrated path covering teacher development, scenario integration, security guarantee and ethical governance, aiming to offer theoretical and practical references for the digital transformation of university physical education.