The ANT+ protocol is covered with the SoftDevices S212 (ANT+ only) and S332 (BLE and ANT+). These SoftDevices are licensed from and available through Dynastream. Information about these SoftDevices and the nRF52, which is in our BMD-300 Series, can be found here.
Nordic Semiconductor's SDK also includes examples for ANT+ here and ANT+ with BLE here. These examples rely on the SoftDevices noted above.