Chen delivers about 250 packages a day. [Photo by Gao Erqiang/Shanghai Star]

Chen delivered at least 350 parcels a day and collected another 600, for about 15 days.

"In one extreme case, a company received five sacks of parcels. I carried all to their front door, sat in piles of packages and called clients to fetch them. I made about 200 calls. After that, my head got dizzy and my ears were buzzing for quite a while," he recalls.

The young man seems confident with his health, though he knows that delivery workers are susceptible to stomach diseases and arthritis.

His lunch time is not fixed. It might be 1 pm or 4 pm, depending on whether he delivers all parcels intact. One day, he found his hands bleeding from the cold. He ignored it. He rides an electric bicycle loaded with parcels but he does not wear a safety helmet.

The most difficult time for Chen is in summer, when his tiny electric bicycle is overwhelmed by heat from passing cars and buses. When he arrives at office buildings, the cool air instantly freezes his sweat-drenched clothes and makes him quiver.

Despite all the hardship, Chen is optimistic. He says the work hones his body and will.

"I am the kind of person who could not enjoy ease. Being busy makes me fulfilled and strong. Now I can walk ceaselessly for a whole day. And I seldom get sick," he says.

Because of his diligence, Chen was chosen among more than 400 delivery men as STO's Excellent Worker of 2014.

Chen dismisses the rumor that a deliver man can easily earn as much as 10,000 yuan a month, saying that is quite rare for front-line couriers. He earns about 6,000 yuan a month and saves most of it.

He does not drink or smoke, or spend his spare time playing computers, which is the major entertainment for many of his colleagues. Nor does he have a girlfriend, as he is "really short of time".

The only thing that he dares to splash money on is perhaps shoes. All his footwear are sports shoes like Nike and Adidas. Last month, he bought six pairs at once.

"The feet are what we delivery workers depend on to make a living and they should be well looked after," he says.