Carrying things on your head/shoulders is surprisingly efficient. Many people can unrack a barbell with double their body weight and just stand there for a bit without having done any strength training at all. The trouble is getting the load into that convenient orientation. Taking something from the ground and putting it over your own head is where all the bad stuff happens. Once it's up there it's not as big a deal.
You can make yourself bulletproof to most forms of hard physical labor by practicing the clean & jerk. This movement is entirely about "get heavy thing off ground and above head" as efficiently and safely as possible. There are advanced movements that can be even more efficient but you trade some injury risk for screwing up. That is to say, the actual amount of wear on your body is even lower if you really know what you're doing.
I don't think you can unrack a 180kg barbell with your head and just stand there like that as a 90kg male, much less untrained. That is a humongous amount of weight.
I definitely don't think this is the case. For somebody who hasn't trained - they're not holding 180kg on their shoulders. I think two big reasons would be that they're not going to have core strength/training to support it, and they wouldn't even have the traps to support the bar on their upper back, it'd dig into them and cause immense pain and probably just roll as well.
For me, it actually seems fairly plausible. I was a fairly untrained 70kg forty-something when I went to the gym and very quickly found that as I did a bit of hiking, I could max out the standing calf raise machine at 155kg. This involves having a very padded 155kg on your shoulders while in a standing position. It felt to me like that was the most my shoulders and back could cope with, and it's more than double body weight.
It’s a huge difference having a loaded barbell which can move in every dimension on your shoulders versus a calf raise machine which is fixed in place and cannot move around!
I’ve squatted barbells since roughly 2006 and the feeling of having more than 100kg on your shoulders is very intense, even if you’ve trained up to it. It feels like it’s crushing your whole body and even breathing is hard.
The idea that an untrained person could put a 180kg barbell on their shoulders and be comfortable AND move around is laughable, they would collapse very quickly.
They wouldn't be able to unrack and stand there either. Just standing with a very heavy barbell is extremely difficult (assuming an untrained person).
Seriously, go and try it, load up 100KG or roughly 225lbs on a barbell and just stand there with it. If you're already a big/heavy/trained guy, put 180KG or 400lbs.
It will probably be quite a surprising experience for you.
And I will say, that even when I was training for heavy squatting, standing there with a very heavy barbell on your back isn't fun at all, you have to have a very tight core, tensed muscles, breathing is much harder. i.e. just standing there is hard work and you want to get your 5 squats done asap. Also, it just plain hurts your back as the metal bar on your spine is painful!
Agree it’s efficient, don’t agree that an untrained person could unbrace double bodyweight.
I weigh 90kg and can squat ~190kg. Having that much on my back feels HEAVY. I think if you haven’t built up to it before you will not be able to do that
It will feel heavy, but you are not lifting it more than a few cm (and at the point where your body has the most leverage).
Remember the point is most humans couldn't get the weight there, but if somehow it already was they could hold it. That isn't a useful thing to do so we rarely test it.
You can make yourself bulletproof to most forms of hard physical labor by practicing the clean & jerk. This movement is entirely about "get heavy thing off ground and above head" as efficiently and safely as possible. There are advanced movements that can be even more efficient but you trade some injury risk for screwing up. That is to say, the actual amount of wear on your body is even lower if you really know what you're doing.