Strain score question

For jogging/running can i use the Relative Number Strava gives me for the Strain score in xert?

Relative Effort number in strave i meant

Or maybe use the new heart rate stress score in Strava for jogging in xert?

I figured it out by checking my score in Training Peaks. It is the rTSS score in there that will work

Yes and no. Ideally you want your XSS to account for the strain that improves cycling, not just general strain from exercise. rTSS doesn’t do that unfortunately.