With the booming of Human-centric multimedia networking (HMN), there are rising amount of human-made multimedia that needs to distribute to consumers with higher speed and efficiency. Hybrid distribution of Client/Server (C/S) and Peer-to-Peer (P2P) have been successfully deployed on the Internet and the practical benefits have been widely reported, while its theoretical performance remains unknown for mass data delivery unfortunately. This paper presents an analytical and experimental study on the performance of accelerating large-scale hybrid distribution over the Internet. In particular, this paper focuses on the user behavior in HMN and establishes a user behavior model based on the Kermack-McKendrick model in epidemiology. Analytical expressions of average delay in HMN are then derived based on C/S, P2P and hybrid distribution, respectively. Our simulation shows how to design and deploy a hybrid distribution system of HMN that helps to bridge the gap between system ultilization and quality of service, which provides direct guidance for practical system design.