Apple Watch 3 and peloton tread

I have an apple watch 3, and a peloton treadmill. I have noticed that when I use my watch to monitor my workout, the distance timed/tracked is significantly different than what the peloton is stating. Both the tread and watch are calibrated with my specific height/weight/stride to capture accurate readings, however when the watch says I've hit 1 mile, the tread says its only .82 of a mile (or thereabouts) Same thing with calories burned. Tread will say I burned one amount, and watch will say another. I wear the tread HRM, and when I check mid run, both the watch and the HRM are the same #. How is this possible?