Piriformis injury- anyone else?

I have had this on and off for well over a decade--in my case it began from a traumatic injury that probably healed badly and left scar tissue, rather than overtraining per se. (I don't think I was running much at the time, nor was I biking; it was before I got into tri.) But running (especially speedwork) and sometimes biking aggravated things. For an acute case, you can try rest, ice, gentle stretching, limiting time spent sitting (which often aggravates things) and avoiding the activity that led to the injury for a few weeks. If you are biking, you might want to take a look at your saddle or bike seat to see if that is causing or aggravating things. Maybe you've built up mileage or intensity too quickly after pregnancy and childbirth? Hard to know without knowing what you were doing before and during the pregnancy, as well as after. It's also possible your body is reacting to hormone changes and/or changes in your center of gravity or running style during pregnancy and then afterwards.

Long-term, I found there was no magic bullet, just keeping after stretching and strengthening the whole kinetic chain, especially hamstrings, glutes, and core muscles. Deep-tissue massage was also useful, as in my case there was some scar tissue that was making my hamstrings and glutes on one side even tighter than the other. I try to pay special attention to recovery (icing, foam rolling or massage, stretching) after hard runs, long rides, or races. You can find exercises online, but if you can find a trainer or physical therapist who works with athletes, that might be useful. I first worked with a PT (actually a former PT who had become a teacher at our school) and later with a triathlon coach on exercises to specifically address weak, tight glutes and hamstrings.

So helpful, thank you! Funny, sitting doesn't bother it at all, just "propelling" myself forward, getting up, and transferring weight pinches.
After I had my son I stopped doing yoga (dumb!) because I didn't have time which I think led my hips to be super tight. The leg/ side that bothers me is also quite a bit shorter than the other one!

I made a bunch of appts with a sports PT and in the meantime I will rest (don't want to!) and roll and stretch I guess!