Described are methods and systems for associating frames in a video of an activity of a person with an event. The methods include recording a video of an activity of a person; storing a time-series of a plurality of sensor data (82) obtained from a sensor assembly (12) of at least one sensor (31, 32, 33, 34, 35) coupled to the person while the person is performing the activity; synchronizing the video with the sensor data (82); detecting an event in the time-series; and associating the event with at least one corresponding frame in the video showing the event.