A distributed, multi-stage, intelligent system is configured to determine user action performance characteristics parameters in action sports. Ruggedness, complexity, and cost are unevenly distributed among components across the stages for improved overall performance and reduced cost. The system includes stage-one, wearable devices configured to use sensors to collect initial data and transfer the initial data to stage-two devices which may temporally store the initial data and/or perform further data processing to generate intermediate data for communication to one or more stage-three devices configured for long term data storage, further processing and presentation.