On a animated TV show (dragon ball Z) characters would have clothes which seamed 3 times there weight. Gradually building up weights (say a pound a day), could one be able to carry evenly across there body 3 times their own weight and feel normal? What would be the upside and downsides?
Now, some work has actually been done on this where scientists looked at what would happen if you were crushed by 2.5g:
There was the hyper-g work done on chickens, for example, by Arthur Hamilton ("Milt") Smith in the 1970s. Milt Smith was a gravity specialist at the University of California at Davis who wanted to find out what would happen to humans if they lived in greater-than-normal g-forces. Naturally, he experimented on animals, and he decided that the animal that most closely resembled man for this specific purpose was the chicken. Chickens, after all, had a posture similar to man's: they walked upright on two legs, they had two non-load-bearing limbs (the wings), and so on. Anyway, Milt Smith and his assistants took a flock of chickens – hundreds of them, in fact – and put them into the two eighteen-foot-long centrifuges in the university's Chronic Acceleration Research Laboratory, as the place was called.
They spun those chickens up to two-and-a-half gs and let them stay there for a good while. In fact, they left them spinning like that day and night, for three to six months or more at a time. The hens went around and around, they clucked and they cackled and they laid their eggs, and as far as those chickens were concerned that was what ordinary life was like: a steady pull of two-and-a-half gs. Some of those chickens spent the larger portion of their lifetimes in that goddamn accelerator.
Well, it was easy to predict what would happen. Their bones would get stronger and their muscles would get bigger – because they had all that extra gravity to work against. A total of twenty-three generations of hens was spun around like this and the same thing happened every time. When the accelerator was turned off, out walked ... great Mambo chicken!
These chronically accelerated fowl were paragons of brute strength and endurance. They'd lost excess body fat, their hearts were pumping out greater-than-normal volumes of blood, and their extensor muscles were bigger than ever. In consequence of all this, the high-g chickens had developed a three-fold increase in their ability to do work, as measured by wingbeating exercises and treadmill tests.
- Smith, A. H, "Physiological Changes Associated with Long-Term Increases in Acceleration." In "Life Sciences and Space Research XIV", edited by P.H.A. Sneath. Berlin:Akademie-Verlag, 1976.
- Smith, A. H., and C. F. Kelly, "Biological Effects of Chronic Acceleration." Naval Research Reviews 18:1 (1965)
- Smith, A. H., and C. F. Kelly, "Influence of Chronic Acceleration upon Growth and Body Composition." Annals of the New York Academy of Sciences 110: 413 (1963)
You can read more in this book: https://www.amazon.ca/Great-Mambo-Chicken-Transhuman-Condition/dp/0201567512
But what you are asking is slightly different in methodology:
Hopefully at some point in your life you have had the experience of putting on chainmail. A full compliment of it weights anything up to 27kg (60lbs). Wearing it feels heavy. A suit of the heaviest plate armour would be about the same on top. With both on you are approaching the weight of a human being evenly spread over your body, pushing you into the floor. It feels crushing, every muscle will be working overtime to stop you crumbling into a ball on the floor. Moving is extremely hard. But, with some gentle progressive overload your muscles could build up to this and get used to it.
Your joints however...
Your joints have cartilage protecting them and tendons holding them together. You can't make tendons stronger and you cant replace cartilage (IIRC). By wearing 3x your bodyweight in clothing your cartilage will be crushed much like butter in a mortar and pestle.
(Get some gristle from a chicken and try this at home in your own mortar and pestle!)
Any fast or sudden movement would put massive strain on your tendons and you would get a LOT of tears.
Eddie Hall is arguably the strongest man alive right now and his maximum deadlift is 500kg with a bodyweight of 185 kg. He only did this for one and ruptured his sinus. He would not be able to support 3x his bodyweight in clothing on the regular.
To answer your question: No, you would be restricted by the maximum power output of a human relative to their bodyweight.
It is interesting to consider that people often do carry their own body-weight, or more, in daily life, and they do increase it gradually to the point it feels normal:
- Extremely overweight people may frequently be carrying so much excess fat that they can lose half their body-weight and still be healthy. e.g. I know people who are 18st who used to be 9st. Granted they are not physically very fit but they live fairly normal, active lives. I myself am probably 3st above the 10st I used to weigh and if you asked me to carry that (20kg) all day I would be exhausted.
- Strongmen may weigh up to around 200kg (30st+). In January 2021, Brian Shaw was measured at having 328lb (149kb, 23st) of lean muscle https://www.youtube.com/watch?v=WdD8qQkOPdI
Neither of these cases is the same as you carrying 2-3X your normal weight around, but they do show you can easily carry your whole bodyweight around as part of 'normal life'. Of course there are even heavier people, the sort who have to be lifted by crane out of their house... but they can not typically live a 'normal life' as activities such as walking become impossible.
That said, according to google the heaviest athlete ever weighed in at 700lb (315kg, 50st) which is equivalent to a reasonably heavy 17st guy carrying 2X his own weight around. But this is a true outlier!