True Fitness Treadmill ES9.0 + ES7.0 Owner's Manual page 41

Use these keys to set up your favorite training speeds.
While the treadmill is operating in manual mode, pressing
and holding either the walk or run key will "save" that speed
as that key's operating speed. Pressing that key will change the
treadmill speed to that speed.
Note: you can't set a higher speed for the walk key than is set
in the run key.
Tip: set the walk key speed first.
The walk+run key uses the speeds set in the walk and run keys
in an interval workout pattern. It alternates every 60 seconds
between the walk speed and the run speed.
Before you customize these keys, the walk key is set to 3 mph,
and the run key is set to 6 mph.
Caution: just a single keypress of these keys will change the
treadmill speed.
Quick Workout Keys
Chapter Four: Custom Workouts
ES Treadmills Owner's Guide
Quick Workout
Keys [walk,
walk+run, run]
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