How was it like then? How did civilians train themselves for the tough situation of physical combat in the old days? And why endangering oneself as such, with the understanding that protective devices or a referee was absent? And finally, how effective can iron shirt be? Able to withstand weapons? Were those marital artists fooling themselves?
To answer these questions, we have to dig into reputable historical texts rather than legendary stories of martial artists or martial arts. History facts can be quite different from myths. The latter is more polemical, faith inducing or motivational in nature. Same for martial arts, same for religions.
In the past decade, researches flourished among academics in China and the West. Much interests have been expressed on the many uprisings (rebellions or revolutions) and the authority's response to such events, in mid to late Qing Dynasty. Many of these researches made use of recently available official documents. These documents were reports of front-line officials written, to inform their superiors, during different stages of the uprisings, and documented confessions of arrested rebels after the event. With the objective for better prevention in future, many Qing Emperors dug deep into the reasons behind such uprisings. So much so, some of the rebels were questioned in details for years before their final execution (leaders were always executed brutally). Another source of information were verbal accounts from the peasants who are still alive today. Due to these efforts, many books were published on societies, groups such as Big Swords Society (大刀會) and White Lotus Buddhist sect (白蓮教).
The Big Knife society was associated with armed civilian groups organized by rich families to protect their villages, oftentimes against bandits (and uprisers). White Lotus was famous in raising armed uprisings against Qing Emperors (interesting enough due to latter widespread and heavy persecution by the authority in late Qing Dynasty, many of these groups turned en-bloc to Christians to seek protection from foreign priests/evangelists).
The gist of the matter is: whenever groups had to engage in serious life-and-death combat situations, they would seek martial artists on Iron shirt (鐡布衫) and Gold Bell shield (金鐘罩) to teach them the techniques. Oftentimes martial artists were successfully recruited to join in the cause of the groups too.
In one of the official reports, there was an account on the training of Iron shirt (鐡布衫) and Gold Bell shield (金鐘罩) - in a report submitted to the Emperor by a front-line official. The report was quoted in "The origins of the Boxer Uprising" (written by Joseph W. Esherick of the University of California, San Diego).
"其习法时，贫者不收贽仪(学费)，有力者以京钱六千为贽，夜半跽而受业，燃灯焚香，取新汲井水供之。以白布画符，其符鄙俚不经，有'周公祖，桃花仙，金 罩铁甲护金身'等字样。传艺者并不能书，或不识字，多遣人代书之。另授以咒，诵咒焚符，冲水令其跪饮，即于灯上吸气遍吹其体，复以砖、棍排击之。诵咒三夜 即能御刀，谓诵久即火器亦不能伤矣。大致略似运气之法，气之所至，猛击以刀可以不入，而稍一顿挫，则仍饮刃也。愚民无知，惊为神术"。(江苏徐州道阮祖棠的报告)
In short the report said, using blessed drink, meditation and mantra under a folk-belief system of inviting spiritual power, a practitioner is transformed into a trance stage. At such stage, his body will be hit with poles and bricks. After three nights of such conditioning (with poles and bricks strikes on his body), sword will be used. The official commented that it was similar with chi-kung. When a practitioner's body is chi-filled, a clean and quick strike by a sword would not harm his body and will be bounced back. However, if the striker (or the practitioner) hesitated, the sword would slit open a practitioner's body.
According to the historians, both rebels and country folks supporting the regime learned Iron shirt or Golden Bell shield. In the rough and tough arena of street fights, the ability to take on punches and weapons (under certain conditions) would definitely be useful.
Nowadays in Hong Kong, there are still practitioners doing the old Iron shirt or Golden Bell shield. They are mostly Taoist sects (see my previous post: A world without miracles). And some martial artists are still fond of demonstrating taking punches (or feet stomp at a height) at the abdomen.