Do you have it plugged into a gfi circuit?
OK let's try to run a heavy duty extension cord to another area of the House. If it trips a different breaker then we will rule out the House as the problem. If it works fine then you know you have an issue with that part of the House.
OK just to be clear you ran the cord to another area in the House and it tripped a completely different breaker this time?
Well without running an extension cord to another plug on another breaker, there is no way to determine if it's the House or the Treadmill.