Suunto SPARTAN SPORT 1.8 User Manual page 31

acceleration, giving more accurate readings at steady running
speeds and a quicker responses to changes in speed.
12
10
8
6
sec
FusedSpeed benefits you the most when you need highly reactive
speed readings during training, for example, when running on
uneven terrain or during interval training. If you temporarily lose
the GPS signal, for example, Suunto Spartan Sport is able to
continue showing accurate speed readings with the help of the GPS
calibrated accelerometer.
30
GPS FusedSpeed
60 90 120
31