Is it possible to sample the accelerometer at a rate faster than 1 Hz? The documentation at http://developer.garmin.com/downloads/connect-iq/monkey-c/doc/Toybox/Sensor/Info.html indicates that the sensor data "can be retrieved on demand", but it looks like the internal sample rate of the accelerometer is still 1 Hz regardless of how fast the app retrieves sensor information.
The Accelerometer API reads from a cached resource on the device and doesn't directly trigger a direct read of the Accel on our devices. Some device update the accelerometer data more frequently than others. When I created the Accelerometer sample, I believe the VivoActive was only updating the data once per second. The Fenix 3 updates the data at a much more rapid rate (at least as fast as the 10Hz timer in the sample).
It would probably be appropriate for the VivoActive to update the resource more often if possible, when a ConnectIQ app has requested sensor permissions, so I will send a request to the device team.