Apple Fitness sometimes does / doesn't record Vertical Oscillation, Ground Contact, & Stride Length

My apple watch SE is updated to the latest OS (10.2) & my iphone is updated as well (17.2.1)

I've tried restarting both. My watch is GPS only model, not cell, & I leave my phone at home while running.

When I get home & open the fitness app on my phone, it shows that day's run with all its metrics. Occasionally the workout details include vertical oscillation, ground contact time, & stride length, but more often than not they are not included.

It seems to display those metrics about 1/5 of the time, and there's no pattern as to when they show up. Long runs, short runs, different routes, etc.

Any ideas why this may be or how to fix it? Thanks in advance.