Even the buttstocks of rifles produced for the PLA needed to be lengthened so as not to affect firing accuracy, the study said.
"The configuration of armaments and military personnel's physique should be matched because that is the only way to ensure handy use of the equipment," said Ding Songtao, director of the survey.
Larger tanks will be the focus of the new generation of roomier battlefield equipment. The low-slung silhouettes of China's existing main battle tanks – designed on a 30-year-old model of the Russian T-series – make them more difficult targets, but their compartments are too cramped for today's beefier crews.
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Owing to better nutrition, China's younger generation are now much taller than their parents, although obesity is a problem. A study by China's health ministry in 2007 showed that urban Chinese boys aged six were 2.5 inches taller and 6.6 pounds heavier on average than boys 30 years ago.
But the conclusion that the PLA's 2.3m active service personnel needed a new range of supersized military hardware was met with derision from some analysts.
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Jiang Lianju, a researcher with the China Academy of Military Sciences, said the size issue was a "very minor consideration" compared with technical specifications such as armour and combat effectiveness.
And Ni Lexiong, a military expert based in Shanghai, said height and weight had always been a consideration in choosing tank crewmen. "Choosing tank operators is like choosing weightlifters – both require men to be short and quick."
Rather than building larger tanks, it was more likely that the inner compartments could be enlarged, keeping their overall size unchanged, he said.