The PT will send cadence data. It estimates it by sensing the pedal stroke through power surges. It does a pretty good job, but sometimes the display will lag behind a couple seconds if you are making a jump or changing cadence quickly. Not great if you are trying to do cadence drills and need to see absolutely real-time data or analyzing what was going on in a sprint second by second. I don't bother with my cadence sensor since getting the PT.