I think some people are making some wild assumptions:
-Most 3rd World/poor nations have terrible runners and athletes. Look at India, huge population, poor, lean people; world's worst athletes.
-HS is not representitive, but is important to measure since if somebody, especially a non-runner is going to go sub-5, they are going to do it in HS.
-Soccer players are constantly overestimating their distance running ability. In college myself and 5 fellow rugby drunks, destroyed, and I mean destroyed, 6 Div 1 soccer players in a 5K challenge they threw at us.
-I think, and someone probably has better stats, running participation in dozens of countries is not existant.
Even amongst runners, sub 5 is a very small group, here is last year's 5th Ave Mile for comparison:
72 of the 2,464 finishers of the 2005, 5th Ave. Mile broke 5:00, including Toby Tanser at 4:57, in a downhill road mile in perfect weather. That's only 2.9% of a pretty selective running population. This does not include the elite groups where 31 of 33 (93.9%) men and women broke 5:00.
Time distribution:
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4:00-4:59 72 or 2.9%
5:00-5:59 553 or 22.4%
6:00-6:59 1,078 or 43.7%
7:00 + 831 or 33.7%
Sex/Age distribution:
Men – 1537 Women – 927 Total – 2464
Finishers by Age and Gender
Age Group Men Women Total
12 - 14 33 29 62
15 - 19 48 20 68
20 - 29 307 300 607
30 - 39 616 354 970
40 - 44 184 74 258
45 - 49 123 62 185
50 - 54 82 29 111
55 - 59 50 20 70
60 - 64 22 8 30
65 - 69 16 3 19
70 - 74 11 5 16
75 - 79 3 2 5
80 - 84 3 0 3
85 - 89 1 0 1
90 - 99 1 0 1