A small part of it is really good physical fitness. For example, when I was in Pu 'er, Yunnan, I knew a scaffolder who could be both an arm and a flag. I think he is more relaxed than the "fitness god" in many videos on the Internet.
But most workers are in poor health for the following reasons:
1, first of all, their diet is very poor, which I have a deep understanding of, because some site managers and workers eat in the same pot, and I have eaten for more than a year. Chefs hired by workers are generally relatives of a foreman, who can't cook at all. Workers' food expenses are costs, so they usually only choose cheap ones.
The most common are dried noodles, boiled cabbage and steamed bread. Add some fat occasionally and no one will eat it. You can't eat that thing if you cook it blindly.
And we often see boys in good shape taking selfies in fitness, not to mention what diet plan (protein and calories) they make for themselves every day, at least the meals at ordinary times are good.
2. Working environment and time. The ultraviolet rays in Yunnan are very strong in summer. Once I checked at the construction site in the morning, I found that my arms and neck were all red in the office in the afternoon, so I could peel a layer of skin directly.
The workers had to work in the hot sun all day. They calculate their money by the day. I have seen some workers drink Huoxiang Zhengqi water to continue their work without rest after heatstroke.
Another year, I worked in the third phase of CITIC in Caishikou, Beijing as a landscaping project. At that time, the construction period was tight (the project was not tight, and everyone hoped to finish it quickly and then sell it to make money). Trucks are not allowed to enter the city during the day, and a load of turf arrives at the construction site at midnight. The workers didn't sleep during the day, but they got up at night to move the turf and didn't finish it until dawn.
This situation is not uncommon, and you have to go out to pick up concrete in winter nights.
Fitness people generally pay great attention to the combination of work and rest. Eight hours of sleep every day can ensure excessive recovery of the body, exercise three times a week, leave rest time for physical recovery ... and so on, while workers have to work every day and have no time for excessive recovery.
-Summary.
This is what I want to express. I hope my answer can help you?