NOVELTY - The system has a communication device that sends information to a portable physical activity sensing system, or to both a user and the portable physical activity sensing system. The portable physical activity sensing system records information about a user's physical activity and sends the information to a separate communication system (18). The separate communication system updates the user's stored information with the information received from the portable physical activity sensing system, where the user can access the updated information stored by the separate communication system.    USE - Exercise system for use at home. Uses include but are not limited to a treadmill, exercise cycle, Nordic style ski exercise device, rower, stepper, hiker, climber, and elliptical exercise device and striding exercise device.    ADVANTAGE - The system can be configured to stimulate a group or class workout environment and synchronizing operation of the exercise devices with exercise programming, and can be controlled by packetized signals received from a trainer. The system enables a user to communicate with a distantly located trainer, and communicates with a communication system that enables real-time communication with a trainer or alternatively access to stored exercise programs without interrupting any control signals that control the exercise device.    DETAILED DESCRIPTION - The exercise system has a sensor e.g. heart rate monitor, blood pressure monitor, blood oxygen level monitor, respiration monitor, accelerometer, pedometer or infrared sensor, which senses a physical activity parameter e.g. heart rate, speed, distance traveled, blood pressure, time, calories burned or acceleration, of a user during the performance of physical activity e.g. walking, running, biking, calisthenics or weight-lifting, by the user. The separate communication system is a portable computing device that is one of a cell phone, a personal digital assistant, a portable digital audio player and a portable computer, or a local server or a remote server.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic block diagram of a computer and associated system that provides a suitable operating environment for an exercise system.    Communication system (18)    Hard disk drive interface (144)    Magnetic disk drive interface (145)    Optical drive interface (148)    Serial port interface (164)    Network interface (180)