At age 47, I've finally managed to successfully get back into training without injuring myself. For the past 6 or 7 years every time I've tried to get back into lifting I've only managed a couple of weeks at best before seriously tearing something or blowing out a joint and then have to stop again for ages to recover. I was able to get past the 2 week barrier and sufficiently build up enough strength to continue without injury by using a Time Under Tension method. Using lighter weights than I normally would and training to 1 minute timed sets with continuous movement and constant tension on the muscle group I've been able to stay injury free. Bench press for example I started with 55kg (usually would use 80 to 90kg - 20 years ago I was doing 150kg) To begin with I come down to chest slowly - taking about 5 seconds to come down and then push back up explosively but not locking out the arms at the top and not pausing at all before slowly coming back down again. Not stopping at the top or bottom but keeping the muscles under load continuously throughout the set. This makes for approximately 6 second reps and gives about 10 reps per 1 minute set. You really feel the burn by the end of the minute. Rest 1 minute and then repeat for a total of 3 sets. I always make sure I can do the full minute so if after one set I know I couldn't complete the next minute at that weight then I drop the weight slightly so that I can do the full minute. Using this method I have built some serious muscle in a very short period and it put less strain on my joints etc, during the rebuilding phase. I'm now at a point where I can lift heavier again without fear of blowing something out. I would definitely recommend this method for anyone struggling with injuries and as a way to mix things up and keep your muscles guessing. Also did this while on a Keto diet, which is often not thought of as being much good for weight training as you are having barely any carbs. I got down to 63kgs (from 72) after 3 weeks on Keto getting down to about 7% bodyfat, it's taken me 4 weeks to put 5kg back on in lean muscle mass so I'm now 68kg and want to get back to 72kg with more muscle mass and hopefully maintain 5-7% bodyfat.