The present invention discloses a method, system, and computer program product for determining user interest in media. The invention can select one of a set of different activity profiles specified within a data store. Each activity profile can include biometric attributes and associated baseline attribute values specific to an activity state. A media stream can be manipulated (e.g., created from environmental inputs and/or played upon a presentation device). Biometric data can be received from a user in proximity to the media stream. The received biometric data can be compared values in the selected activity profile. An interest level in the media stream can be determined based on comparison differences. A programmatic action can be performed relating to the media stream based upon the determined interest level. For example, a bitrate of the media and/or a marker in the media can be modified based on interest level.