The present invention is directed to systems and methods for monitoring performance of a variety of activities, preferably including swimming, in a number of states. The invention may comprise an analytics application, a primary device and, optionally, one or more secondary devices or third-party devices for sensing characteristics of the performance of an activity or the environment in which it is performed. The devices are worn during the performance of the activity and contain sensors, preferably accelerometers, for sensing information pertaining to the performance of one or more activities. The information sensed may be provided to a user in the form of real-time feedback and/or made available for long-term analytics and tracking.
