How not to prepare for backpacking ..getting to know 'uncle rhabdo'

A while ago I thought hey, since I'll be traveling again and since I am my own mule it would appear smart to do some ..physical.. preparations. Being an office slave does not have the benefits of being a quarry kind of slave, i.e. you don't become super muscular and start on a quest to destroy the empire of your enslaver to then found your own kingdom.
So I thought it would be beneficial to do something for my back. Having done all this taxing mental work I retired the idea. However randomly a colleague was getting scared of his belly protruding too much and asked me if I wanted to join in with his program. I thought the stars had obviously aligned(but didn't check..!) and this was to be the first step to godhood. As such I agreed already seeing myself wielding .... insanely oversized backpacks. Of course the program was targeting the whole body, but I thought that was an acceptable price to pay and the people in the program plan with every muscle chiseled out didn't succeed to scare me off even though they do look exhausted and out of breath. The colleague assured me that he had started the program before, but then got sidetracked and that the insane amount of repetitions was ok.

After some delays we started midweek and then started all over again the following week. I was sceptical of training over sore muscles etc.. but yeah my colleague had done it before and it's all just bodyweight exercises. So that all went fine until we hit week three of the program.
That was the first time we were supposed to do pullups and 50 pullups at that. Now I thought like: "WTF!?!" .. but yeah colleague ..before. So we went ahead and I just went through with it, surprised it didn't seem as bad as expected. Then during the following 100 pushups, I started to not be able to go for the full range of motion anymore, i.e. I couldn't press myself up completely anymore. According to my colleague the fun would just begin with the sore muscles and that we would resemble T-Rexes. Indeed that was what happened, walking around with arms in a 90° angle, because that was the only option, but then this didn't go away and at some point we suddenly had swollen arms. It looked a bit like we suddenly had gone massively overweight.. in our arms only, but even then there would be some kind of arm shape whereas we looked more like we had some kind of stuffed to the brim giant sausages on our sides.
It took three weeks to disappear all in all I think and foolishly at some point we exercised even with those arms a few times.

So after some point we found out that this most likely had been rhabdomyolisis and we could have suffered renal failure and died.
In other words we had gone too far and caused too much damage to the muscles. Now it turns out this is not uncommon in the so called crossfit scene where this has been dubbed 'uncle rhabdo'. While some people have a disposition for this, the common technique to induce it via execrcise is copious amounts of negative repetitions. Pullups are one of the most efficient means of acquisition.
Of course after this I have completely lost motivation to continue this program ("freeletics") since the program motivates people to keep going no matter what and that everybody could do it. There was no warning at all. For people reading this but who still want to continue their high volume training, please be careful and maybe limit the amount of additional negative only reptitions to no more than the amount full repitions you can do (i.e. 10 full + 10 negative repetitions). Also even if your program says so, don't go with insane amounts of repetitions for a new exercise, instead work your way up. Should you desire to kill yourself, there are way better ways than renal failure!

Now after that it took forever(more than a month) for me to be able to do even a single pullup again, and I am not yet back to the way I was before(in amount of pullups).

So I learned from this, that people I barely know see me walking around all the time in the city(with sausage arms), whereas I rarely see anyone. Further I am weird because others doing this kind of exercising say they feel so great after completing on of those workouts whereas I am just glad it's over. I also don't quite understand how people enjoy to inflict this kind of torture on themselves - what's the fun in having sore muscles every day? And what's the point of all this training when you never have the strength left to do other things after a session?