Where are you getting this? The study was about various intensities of cardio - I didn't see it noted, but I'm guessing the high- and medium-intensity groups were on a treadmill, elliptical, or similar. Pretty small chance of injury for the durations they mention, especially as the subjects were monitored while exercising.
And I'm not really surprised by the study - building lean muscle mass takes resistance training, which wasn't part of the study. The study results appear to be inline with what was common knowledge/experience.
And if you're injuring yourself regularly during weight training or other gym activities, I'd suggest you might hire a good coach/trainer for guidance and programming, because that shouldn't happen either.
After a certain age, it's difficult to train somewhat intensely without risking injury. You can always find some exercises that work and maintain a physical activity, but this may not be enough to maintain your muscle mass or your stamina.
Not sure a trainer is a silver bullet. After 50, it gets increasingly harder to improve as we become more and more injury-prone and start developing chronic issues. Staying active and fit should be reachable for most, but high-intensity or competitive sports become a privilege for those with good genetics. Most of us switch to low-impact sports such as cycling, swimming, hiking, bodyweight training and so on...
I love me some adult coed soccer. And it can be very high intensity intermittently if you feel like it.
(I recommend the book w that title by Ryan Holiday)
To build muscle, you need to push yourself to a limit. You can reduce the weight and increase the repetitions. This approach is just as effective and lowers the risk of injury.
It's not that unusual for people to pick up e.g. powerlifting past 50 and still get to levels well beyond what most younger adults can lift.
I'm 51, and recently back into powerlifting after many years out of it, and I certainly expect to build back muscle and improving week over week for many years before I can't stem the decline any more, as long as avoid injury or health issues that takes me out of the gym - avoiding time off exercise is the biggest challenge with getting older.
But more than a week and you'll typically need to deload to avoid DOMS. More than a few weeks and it will start taking significant time to work back up, and a lot of injuries happens because people try to rush that recovery and add even more time to that.
If you regularly lose weeks at higher age, it quickly becomes tricky to avoid tipping over into lasting decline.
Lowered the load, increased repetitions and basically nothing for a decade. I can still go almost to the failure, I don't even want to reach it since I don't care about that extra bit. Squats or deadlifts are hard even when not at limits, one feels used body parts for a day or two.
I still add cardio on top of that, its just basic logic of moving around a lot is very good for the body, even if effects are not immediately obvious.
That’s just regular ‘ol DOMS and not a problem.
Tendons tend to respond well to both heavy load or high reps, albeit adaptation in either case is very slow.
These days its more about 15 reps, still 3 sets (plus one just 20kg barbel warmup). When I feel like I could do more, i add 3 or 5 reps, and/or do things slower, especially the lowering part. Weight wise its cca 60kg deadlifts, 50kg squats. I feel like I could do more, but with worse form and thats not a good idea.
There are similar numbers for bench presses, dumbbell curls and few other exercises I sometimes add to mix.
I was never bodybuilder and never looked accordingly but I didn't care, any strong-enough body is attractive to females, good confidence is present and connection to one's body is very good. It was always just training for actual stuff - long hikes, climbing, ski touring etc. Now with kids and after quite brutal paragliding accident that left me wheelchair-bound for few weeks, walked after 6 months and have some permanent changes in calcaneus, I am happy with anything and above is good enough for me, just need to sustain it.
This is such a strange thing to hear, as someone who also has gone to the gym a couple times per week for my life with a lot of different gym buddies.
I would suggest considering a reset of your gym routine and gym knowledge, possibly with the help of a physical therapist to see what you’re doing wrong.
If you’re going to one of those gyms that encourage dumb things like doing heavy lifts in a timed competition format or other bad ideas that were trendy in the 2010s, I really recommend getting out of those environments.
I use the weight training to surface the injuries to make me aware of what I'm doing wrong in daily movements. I might finally be past this and able to just go in and push weights but it's taken years. I feel like it's down to the body I'm living in and what I consider a pain threshold, not any risk taking or lack of information.
You don’t need to be pedantic about the 80% number.
Some people believe "high intensity" means lifting as much as possible as fast as possible, I'd say more reps and deliberately slow movements are as intense for the purpose of staying in shape/healthy.
Most body weight exercises are virtually impossible to fuck up to the point of injury, done properly they'll keep you fitter than 99% of the population
My son is and once subluxed his shoulder while running
I think the bigger problem is that, as far as I can tell, very few people have the appropriate personality type for high intensity exercise. Most people seem to experience it just as pointless discomfort.