(Telecompaper) The fitness wearables market is projected to treble to over USD 10 billion of hardware revenue by 2020, compared to an estimated USD 3.3 billion this year, according to Juniper Research. The growth will be largely driven by sales of wrist-based trackers, while hundreds of thousands of connected garments used by professional sports teams will showcase the most advanced capabilities in areas such as tracking. The NFL and others have partnered with Microsoft and Zebra Technologies for live data visualisation and new ways for fans to understand games. Devices offering heart-rate tracking, blood-oxygen levels and other advanced fitness tracking capabilities are becoming more popular. Juniper sees a potential risk if too few compelling wearable apps reach market. Biometrics could become part of athletes' contracts and play a role in hiring practices, according to research author James Moar, who said clear boundaries are needed for data ownership and use, with opt-out provisions.