What are the forerunner GPS?
Its a heart rate monitor + GPS combined with software to analyze all the various data points to provide the ultimate personal trainer. A system that is geared for the athlete who is focused on continually improving their performance.

The Heart Rate Monitor:
A heart rate monitor is a device that allows a user to measure his or her heart rate in real time. It usually consists of two elements: a chest strap transmitter and a wrist receiver (which usually doubles as a watch). Strapless heart rate monitors are available as well, but lack some of the functionality of the original design. Advanced models additionally measure heart rate variability to assess a user's fitness.

The heart rate monitor was invented by the Australian physicist, Robert Treffene. He appeared on the television show The New Inventors with his device, which was made with swimmers in mind.

The first EKG accurate wireless heart rate monitor was invented by Polar Electro in 1977 as a training tool for the Finnish National Cross Country Ski Team. The concept of "intensity training" by heart rate swept the athletic world in the eighties. By the 1990's individuals were looking to heart rate monitors not only for performance training needs, but also for achieving everyday fitness goals. Today, the same concept of heart rate training is being used by world-class athletes as well as everyday people.

The chest strap has electrodes in contact with the skin to monitor the electrical voltages in the heart (see electrocardiography for more details). When a heart beat is detected a radio signal is sent out which the receiver uses to determine the current heart rate. More expensive monitors send a unique coded signal from the chest strap, and this prevents a user's wrist receiver from receiving signals from other nearby transmitters ("cross-talk.")

There are a wide number of receiver designs, with all sorts of advanced features. These include average heart rate over exercise period, time in a specific heart rate zone, calories burned, and detailed logging that can be downloaded to a computer.

The GPS:
The Global Positioning System (GPS), is currently the only fully-functional Global Navigation Satellite System (GNSS). More than two dozen GPS satellites are in medium Earth orbit, transmitting signals allowing GPS receivers to determine the receiver's location, speed and direction.

Since the first experimental satellite was launched in 1978, GPS has become an indispensable aid to navigation around the world, and an important tool for map-making and land surveying. GPS also provides a precise time reference used in many applications including scientific study of earthquakes, and synchronization of telecommunications networks.

Developed by the United States Department of Defense, it is officially named NAVSTAR GPS (NAVigation Satellite Timing And Ranging Global Positioning System). The satellite constellation is managed by the United States Air Force 50th Space Wing. Although the cost of maintaining the system is approximately US$400 million per year, including the replacement of aging satellites, GPS is free for civilian use as a public good.

In addition to the Heart Rate Monitor and the GPS system, is the management of all the data utilizing the Motionbased web application which does the following:

Storage
Save data to PC
Save data to Internet for storage and sharing
Online data backup
Automatic software upgrades
Browse and organize by activity type
Browse and organize by location
Analysis
Activity-based analytics
Time metrics broken out in tables and charts
Distance metrics broken out in tables and charts
Speed metrics broken out in tables and charts
Elevation metrics broken out in tables and charts
Heart Rate metrics broken out in tables and charts
Cadence metrics broken out in tables and charts
Lap data broken out in tables and charts
Recount weather data to specific activity
Cumulative reports broken out by activity type and period
Display number of stops
Break-out data by uphill, downhill, and flat grades
Break out distance splits
Mapping
View elevation profile
View route on street, satellite, topo, and elevation maps
Simulate ride on elevation profile and maps
Interactive maps displaying real-time data
Dot Racing™
Heart Rate by location
Cadence by location
Browse activities via Google Maps
Community
Browse for activities from others that match search criteria
Share and compare data with others
Email A Friend activity
Export Capabilities
Google Earth
GPX Files
Courses
Workouts
Data Cleaning
Smart Start/Finish
Smoothing Algorithms
Auto-Correction Preferences
Elevation Corrections
Combine activities
Planning
Create custom workouts
Schedule workouts
Create custom courses for navigation and racing/pacing

Together, this allows the athlete a way to analyze their performance to improve their results.