Interesting reads on the front page regarding runners from the 18th century. I was curious as to what others' thoughts were as well. While I believe that runners from that era put up performances that exceed what we give them credit for, I find it unlikely that someone ran sub 4 back then. While a legitimate sub 4 mile from pre-1800 would surprise me a great deal, I would not be overly surprised to hear someone ran 4:15. I had a few thoughts when reading the articles.
1. Training regimens. One of the arguments against fast performances in the 18th century is the developments that have been made in the area of training techniques. However, Bannister didn't appear to have what many would consider advanced training techniques. Nor do the Kenyans at a young age. It is not until they are older and get into a training camp that they get more structure, which is after they have already spent years building up their aerobic base. And it was in the less structured and less scientifically-focused 1970s that the US had some of its greatest success in distance running.
The training is a huge question. Were these guys running 60+ miles a week from a young age to and from school each day? Or did their training consist of challenging others to races and then hammering out 4 to 5 mile runs 5 times a week for a couple weeks leading up to the race?
2. Lifestyle. The lifestyle of people living in England in the 18th century was probably much better suited toward distance running. More manual labor, more walking, etc. The switch to amateurism is interesting because the people who promoted it were probably more likely to be aristocrats who led a less physically demanding lifestyle and didn't have the incentive of going after money. Essentially stripping away two of the primary drivers of the earlier runners.
3. Courses. I believe this is a big one. Downhill courses and straight-aways with a tailwind definitely would have had a significant impact.
Unfortunately, there probably won't ever be a sufficient amount of information to verify or refute the claims. But it is interesting to think about. And who knows what one could find if you went really far back. There might have been some good Australopithecus ultra-marathoners a few million years ago. Primitive humans who were small in stature, spreading throughout the world and forced to cover vast distances to find food. Could be a winning combination.