Fitbit Product Experts Alumni are retired members of the Fitbit Product Expert Program. Learn more
Fitbit is fairly fussy about tracking steps. It needs to detect the impact of your foot landing to identify a step. As you don't get this on a bike you won't get steps. Having said that you may get some from random movement of the arm but not as many as you may be expecting.
Some people try to trick the system by putting the fitbit on their shoe. This gives more steps but not accurate calories.
The bottom line is that you don't take steps on a bike.
Best Answer