Heart rate technology has been around since the 1970’s. Many international soccer teams have been using the technology for years, and the most common practice has been to track through individual monitors and a stopwatch to analyze how players are reacting to and recovering from a workout. The quality of this technology has continued to improve and team USA has recently jumped on the bandwagon. With the men’s national soccer team measuring fitness by way of staffers turning heart rates and other fitness data into spreadsheets, it seemed time to make a leap forward. That’s why U.S. Soccer has teamed up with fitness technology company Polar.