#1: VO2 max is correlated with running a fast mile but is far from the sole factor in determining someone's capabilities.
#2: Someone with a naturally high VO2 max prior to training will generally reap fewer returns to training than someone with a low untrained max (someone who runs 4:40 untrained will have less room for improvement than someone who runs 9:20). And I don't know how long the time frame is on those studies, but I doubt a "typical" untrained person could only improve their VO2 max by 20% after say 10 years of intense training.
#3: A 15% increase in VO2 max and a 10% increase in running economy is approximately a 25% increase in velocity. Let us not forget how much time people could shave off solely by dropping a few pounds.
#4: If you ran 5:05 1600m off of no training you had the ability to run faster than 4:57, now you are trying to justify your not doing so with "exercise physiology."[/quote]
#1: Yes, you are correct, but someone with a low VO2 is not going to run a fast mile regardless of how good thier economy is.
#2: VO2 max improvement is generally achieved in under 2 years, after which large increases are not likely to occur. Therfore, afterwards, improvements are based on improvement of economy and muscle recruitment patterns, and thus also why runners tend to plateau after a certain period of time. 10 years of training is not needed to maximize an individual's VO2.
#3: Yes, people could shave off a few seconds by losing weight, improving economy, etc, but they are not going to reap massive improvements in time from these.
#4: Yes, I could have run faster as a high schooler, and probably could have run faster as a 20 something had I not quit running at the time. However, I am never going to break 4 minutes for the mile, and that is based on physiology. maybe I could have gone down to 4:30, who knows? I'm not trying to justify anything, I'm proud of the fact that I was able to finally break 5 minutes as an adult when I learned how to train properly, wished I would have maximized what talent I had been given as a high schooler/collegian, but also recognize the fact that know amount of willpower is going to overcome physical limitations.