As a person who was a power lifter for over 20 years, I can say that I'm personally against anything "high intensity" with heavy weights.
This will probably be a very unpopular statement, but as one who suffers from having participated in every fad imaginable when it came to weights (with the notable exception of Crossfit, for which I was too sensible to fall), I have also suffered (and continue to suffer) the results of those fads.
First off, stop working out emotionally. No, I don't mean stop screaming or "getting mad" when you work out, I mean stop evaluating your workouts based on how you feel. I have seen people go back and do extra sets or even entire workouts because they didn't think they'd worked out hard enough.
Here's a deep, dark Secret that most people simply refuse to accept: If you work out, even slightly, you will see improvements. As long as you try to progress, your body will do so (unless there's something physically wrong with you).
For example: I would work out the typical 4-zones in a standard way: Monday would be Back and Biceps; Tuesday would be Chest and Triceps; Wednesday I would take off; Thursday would be legs; Friday would be Shoulders, Forearms and Traps; I would then take Saturday and Sunday off and do the same workout the next week. Oh, sure, I'd change up the lifts and intensity, but I would make sure that I was in the gym working out the appropriate zone on the assigned day.
If I was sore, I still worked out. on high-intensity weeks, I'd throw myself into the workouts doing whatever I had to do to complete the goals.
Today, my joints, tendons and ligaments are much the worse for wear. Yes, I gained size. Yes, I gained massive strength. For the longest time, I had a limited range of motion, but I fixed that in the five years before I quit by having a mobility coach in addition to my strength and conditioning coach.
But here's the deal: I noticed something interesting. During the latter part of that twenty years, I did a lot of coaching for amateur sports teams. Most of these teams were for recreational sports where the participants seldom practiced more than 2 or 3 times a week, if that.
I noticed that the players who weren't as "committed" to working out still improved. Eventually, due to the nature of the sports, I noticed that the ones who stuck to it would seem to plateau, physically, at about the same levels. . .just a different times. Where the "hard core" players might do it in two or three months, the others would catch up in 6-8. Everyone would seem to remain there and continue to slowly improve as long as they continued to play. Once the season was over, they all would soon return to Square One at almost the same levels.
I submit that going slower, maintaining a continued and controlled progression, without the high-intensity slamming and forced exhaustion of muscles and other body parts will still get you the results you want, just at a slower rate than you may wish.
I am just now getting back into training following a multi-year forced hiatus stemming from injuries and family situations, and I promise you, It's going to be a much slower and gentler lifting routine than I did all those years. My joints simply can't take that much strain or stress, anymore.
The Professor