The great success of the Internet has raised new challenges in terms of applications and user satisfaction. Web applications demand requirements, such as performance and scalability, in order to guarantee quality of service (QoS) to users. Due to these requirements, QoS has become a special topic of interest and many mechanisms to provide it have been proposed. Those mechanisms fail to consider aspects related to reactivity, i.e., how the users react to variable server response time. This work addresses the use of reactivity to provide new strategies. We design and evaluate a reactivity-based scheduling mechanism that gives priority according to user behavior. We also propose a hybrid admission control and scheduling mechanism that combines both reactive approaches. The results show benefits in terms of response time and user satisfaction.