You can choose the recording interval in rec interval in Menu.
You can choose between five recording intervals:
When browsing through the intervals, the available recording time is shown in the lower part of the display.
To choose a recording interval:
Short lasting activities with fast changes in altitude is better to record with faster recording interval (e.g. downhill skiing). Again, long time activities with slower changes in altitude is better to record with slower recording interval (e.g. hiking)