Something to add about the industrial revolution is that it brought with it some serious increases in polution because of industrial byproducts that were not disposed of properly, ex: lead and mercury and more recently (1900's) PCB's and Dioxins. Hence the reason why women should never eat meat from large predatory fish while pregnant because of problems mercury can cause to a developling fetus.
http://www.cfsan.fda.gov/~dms/admehg3.html

Alex

For a different sort of comparison...

Many Chinese Qing Dynasty (1644 to 1911) Imperial Guardsmen are known to have been over 2 metres (6' 5") tall.

These were elite, highly trained fighters, not shock troops. There does not appear to be any loss of coordination at all, rather the contrary.

about the tiny doorways of for example the house of captain cook, dont we have MEASUREMENTS?? i mean this isnt the bronze age, this was arguably the period that got us obsessed with writing down every detail.
dont we have records of hieght from the 18th century onwards of more than just the king and his buddies

as for french hieght, i remember hearing that napoleon chose only the tallest men to serve, and, thanks to the massive casualties of the era, the french average hieght SHRUNK for a short while.

Wasn't the guy from 6th century Trossingen 180-something centimetres tall? Obviously, height has varied greatly over time.