It's almost redundant to say, but stretching before every workout is just way underrated. I used to do 7 min. on the bike and considered myself warmed up. I also used to think a life of slowly accelerating chronic pains was unavoidable.
Ok I'm more than a few years older than you guys but if my beat up physique can recover then yours should have an easy time of it or you need to visit the doc.
Obviously the whole idea is to increase mobility and reduce pain. YTWL, bodyweight lunges, hip crossover, lying opposites, etc, etc. 6-8 of your choice gives your body the chance to work through it's natural range of motion before you start taxing it.
Another thing I used to do when I wasn't 100% was to ignore the problem by working around it. Just substitute one exercise for anther and pretend it's business as usual when it obviously wasn't. Stop pushing and let yourself heal.
I spent too much time spinning my wheels before I learned to back off and work on increasing overall conditioning. Patience is required but otherwise your just setting yourself up for more grief by stressing out the rest of your system as well. I would always remember the theme from Rocky: "Getting stronger..." to keep me on track. [

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The holistic approach rather than body part orientation works better for getting well just as it does for normal weight training.
Increase rep ranges and intensity by reducing time between sets. A more MMA type workout. The old fashioned grouping exercises by apposite muscle (A1- bench A2- row; B1- leg press B2- GHR, etc.) was helpful.
Intense or DC stretching is superb at this time and, of course, visit your friend the foam roller after every workout.
I don't want to preach to the OP. Korin, and SL also, you both impress me as having a superior sense of knowing what you want and knowing how to achieve it. On the other hand, in the face of the unexpected, I hope you'll consider some of my ideas.