i am fifty. and i know what you are experiencing. i had to get smarter about working out.
what has worked for me is that i can't go back to back days super hard workout.
i can lift 4 days per week. of those days, i can do 3 decent workouts, and one very hard (for me, anyway) workout.
i also pay MUCH more attention to flexibility and rolling out.
i do at least a few minutes of this every day.
my body is also more sensitive to food.
i cant eat like crap and max out in the gym
have to eat relatively cleanly.
also on heavy days, i need to avoid food 2 1/2- 3 hours before lifting.
it was tough for me to realise that the glory days were over, but, once i adapted to what my body was letting me do, i can still throw around some heavy weights- just as much as before, just not as often as before