It is natural to assume that exercise would have a positive effect on the length of life for middle-aged men given all of the medical literature that has been published in the past showing a positive correlation between exercise and longevity. In this particular argument, the writer puts forth a study purporting to track five hundred middle-aged men with different occupations in different parts of the country. The survey was apparently conducted on the basis of an annual survey asking how often and how strenuously these men exercised. The writer not only concludes that there is a clear link between longevity and exercise, but that doctors should not recommend moderate exercise, rather vigorous outdoor exercise on a daily basis to all their patients. This writer's argument fails to convince in a number of areas due to several lapses in logical thinking.
The first and most glaring error in logic lies in the fact that the results of only two types of exercising men are reported: those that exercise strenuously outdoors almost every day and those that only had mild exercise once or twice per week. There are no other results mentioned from the survey, such as the results of men who exercise vigorously indoors every day, or those that exercise moderately either indoors or outdoors three or four times per week. Additionally, it is likely that those men that are exercising outdoors vigorously and almost every day are already in better health than those men that only exercise mildly once or twice per week. Unhealthy men, either due to obesity, smoking or other health-related problems, would naturally be expected to exercise less and die sooner than those apparently healthy men who are physically able to exercise strenuously every day.
Finally, the argument suffers from a critical flaw in its conclusion when the writer states that doctors should not recommend moderate exercise for their patients, instead stating that they should only encourage vigorous outdoor exercise on a daily basis. This conclusion is supported by absolutely no evidence in the argument - indeed moderate exercise is not even mentioned until the end of the editorial. Additionally, the argument fails to take into account that the study only addresses men, not women or children that are also doctors' patients. Furthermore, for some men, women or children, outdoor vigorous exercise on a daily basis might actually be detrimental to their health, such as those at risk for a heart attack or living in harsh climates. or even we can make an example that a working ball mill cannot be rusty.