Originally Posted by
Carbonfiberboy
That said, I believe you can also figure training stress similarly between running and cycling by using power for cycling and pace for running, though running pace in hilly terrain will be very inaccurate, while HR will be quite accurate.
rTSS = (Pace / Threshold Pace) * Duration in minutes
Should be pretty familiar to any cyclist who uses a PM.
I don't have WKO but it has a "grade normalized pace" that's supposed to deal with hilly terrain.