During a live stream of a main content to a user, a biometric response of the user is measured during a first streamed portion of the main content. The biometric response is analyzed to detect an event in the first streamed portion of the main content. The biometric response of the user during the event indicates that the event is a user-specific climactic event. Based on the analysis, a user-specific set of feature values is computed that are representative of the user-specific climactic event in the first streamed portion of the main content. A user-specific non-climactic period is forecasted in a future portion of the live stream during which a likelihood of an occurrence of any user-specific climactic event is below a threshold likelihood. A secondary content is inserted during the user-specific non-climactic period.