You can either choose to lift until you find a sweet spot of strength you are content with and not push past it, avoiding injury from ever-heavier lifts. Or you'll want to progress slower when you are at intermediate-advanced level, lifting is pretty safe as a sport if you do it with proper form until you get to the upper boundaries.
Rest well, eat enough, don't push it when something is feeling a "little weird" with some muscle. My worst injury as a beginner 10+ years ago was to finish a deadlift routine after feeling a muscle slightly pulled after the first rep, I had a bad lower back pain for weeks that left me uncomfortable doing anything: laying down, sitting, walking, etc.
If you don't know any bodybuilders I'd recommend getting a good coach on your beginner phase to fix your form, you don't need to keep a coach after you learn the basics, and bad form is the #1 source of injuries at lowest levels. Starting Strength is a decent beginner routine but over time you'll want to add some auxiliary exercises to work smaller muscles, in my routine I like to start the training session with big lifts (deadlift, squat, standing barbell rows, chin ups/pull ups, bench press, and overhead presses) and after those I follow with auxiliary movements (face pulls, dumbbell presses/curls, calves, etc.).
I chose to not push myself past a level I got comfortable with, never tried a deadlift heavier than 220kg, my squats hover between 130-140kg, bench press around 80kg, military press around 55-60kg. I feel strong enough and been injury-free for years, it's a good maintenance level and my goal with lifting has always to just keep mobility in older age, not to keep growing muscles/strength as far as I could push.
Also for most people being able comfortably deadlift even 1x of their weight in a set would be big improvement and they would probably get most of the benefits.
The problem is once people get to that - why would they stop?
I’m 40. I do 3 sets of 8 deadlifts about 5-10% over my body weight. This routine wears me out but each single rep feels easy. I can do this routine every day. You could say I’m maintaining, but I’m still reaping benefits years later. I consider it effective cross training for cycling. In between sets I do bicep curls and tricep kickbacks. My goal is to find a routine that will follow me until old age.
Especially if you're a cyclist, I think maintenance weight training like this is huge. Cycling, for all it's benefits, seems to be more likely to have a negative impact on bone density than a positive one.
For me it was when I start noticing that the bad days where I'd fail my intended lift happened more often than the days I progressed.
An example, when I was trying to push my bench press over 87,5kg I was going with 1-2 sets of warm-up (~8-10x 70kg then adding 5kg to the 2nd warm up), followed by: 1 set of 5x85kg, 5x87,5kg and trying to go 3x90kg but noticed I was failing the 3x90kg set for 4+ weeks in a row, I kinda knew it was going to take more effort and a different approach than just my very basic way to increase load, I was happy with lifting 87,5kg on the bench and just stopped trying to push it further.
Age has definitely affected my recovery time, stamina, etc. but because I've been lifting on-off since my teens playing tennis, and only focusing on strength training for its own sake later in my 20s. I do have a "baseline" that I can reach in about 4-6 months even when I stop training completely for a while, the strength you gain changes your muscles (I think it creates extra nuclei in muscle cells, unsure how true that is, lots of pseudoscience in fitness-world) and it comes back. That's one of the main reasons I recommend all of my sedentary friends to try lifting for a while, it will help when one is older.
-Develop excellent technique.
-Learn to stop at technical failure, never muscle up reps at any cost.
-Focus on slow eccentrics, deep stretches under load.
-Keep your sets over 10 reps.
From some age on (40-50?) you have to train to maintain, not to improve. Some can train really hard up to old age but most people tend to accumulate nagging injuries that can take away the ability to train at all.
Don't exceed your recovery resources. Anecdotal reports are not helpful when determining injury risk.
Overall injury incidence in strength sports is very low. But if you do it to compete, maybe there is an argument to be made that pushing the limits increases it.
Overall though, the much greater risk is to not train. Whether you do barbell movements or machines is not a determinant of of health outcomes, as far as we know.
I would not put stock in anecdote without some numbers on injuries among non-competing powerlifters.
Rest well, eat enough, don't push it when something is feeling a "little weird" with some muscle. My worst injury as a beginner 10+ years ago was to finish a deadlift routine after feeling a muscle slightly pulled after the first rep, I had a bad lower back pain for weeks that left me uncomfortable doing anything: laying down, sitting, walking, etc.
If you don't know any bodybuilders I'd recommend getting a good coach on your beginner phase to fix your form, you don't need to keep a coach after you learn the basics, and bad form is the #1 source of injuries at lowest levels. Starting Strength is a decent beginner routine but over time you'll want to add some auxiliary exercises to work smaller muscles, in my routine I like to start the training session with big lifts (deadlift, squat, standing barbell rows, chin ups/pull ups, bench press, and overhead presses) and after those I follow with auxiliary movements (face pulls, dumbbell presses/curls, calves, etc.).
I chose to not push myself past a level I got comfortable with, never tried a deadlift heavier than 220kg, my squats hover between 130-140kg, bench press around 80kg, military press around 55-60kg. I feel strong enough and been injury-free for years, it's a good maintenance level and my goal with lifting has always to just keep mobility in older age, not to keep growing muscles/strength as far as I could push.