Economics, Literature and Scepticism

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I am a PhD student in Economics. I am originally from South Africa and plan to return there after my PhD. I completed my M. Comm in Economics and my MA In Creative Writing (Poetry) at the University of Cape Town, where I worked as a lecturer before starting my PhD.

Saturday, September 12, 2009

The Man Who Invented Exercise

Posted by Simon Halliday | Saturday, September 12, 2009 | Category: , |

I thoroughly enjoyed this Financial Times article on about Jerry Morris, one of the first scientists to pick up a positive correlation between health and exercise.  Apart from the enjoyable reportage, the short biography, etc, what struck me was the simplicity in the setup for which Morris was able to detect a pattern.  I will describe it slightly differently, just to show how ideally it is suited to a quasi-experimental approach. a group of a few thousand people of roughly the same socio-economic status. Assign about one half of the group to one job, the other half to another on the basis of some random criterion.  Observe that members of the one group live longer than the members of the other seemingly as a consequence of doing the one job and not the other.  Try to interrogate the differences between the jobs, isolate this difference, and voilĂ .  So this is what Morris had: take the two people who work on buses in England during the 40s: a bus conductor and a bus driver.  Both men (and they were all men I believe) were from the same socio-economic background (class) and basically didn't require any particularly different qualifications - driving itself being quite common.  But, for some reason, the risk of heart attack for a driver was roughly double that of a conductor. What, then, separates the activities of a conductor from a driver to explain this? A conductor walks all the time and climbs between 500 and 750 steps during his shift every day, whereas a bus driver remains sedentary. This was the only factor that could legitimately explain the differences in outcome and was set up so well as to be an experiment, what we call a 'natural experiment' or a 'quasi-experimental' setup.

So, as an empiricist, the article appealed to me on grounds factual, biographical, and technical.  What an intriguing tale.  Well done to Kuper for the entertaining read.  Well done to Morris for establishing the connection between vigorous exercise and health. Coincidentally, I also support Morris's idea that exercise needs to be made more easily accessible - pedestrianised areas to encourage walking, bicycle paths to encourage cycling, accessible and inexpensive swimming pools for swimming, that champion of full-body exercises, and, I believe, accessible public transport to and from which one can walk and access resources like parks, pools and gyms.  We shall see.

Currently have 1 comments:

  1. Si, just perusing your old notes. Enjoyed this and of course am an advocate of the findings on exercise and well-being :o) But it strikes me that with a more modern understanding of stress and related illness, one might come to a very different conclusion on differences in outcome for bus driver and conductor - e.g. that driver has more psychological responsibility for well-being of passengers and risks of crash, as well as greater requirement for constant vigilance while not having as much support (can't talk to people while driving), etc. Just a throwaway thought!