Joyner et al. J Appl Physiol.2010; 0: japplphysiol.00563.2010v1-jap.00563.2010
Pay to read it here: http://jap.physiology.org/cgi/reprint/japplphysiol.00563.2010v1
The cite is in a part that says, "What will the Two-Hour Marathoner Look Like?
Forty-one of the 50 fastest marathons have been run by Kenyans or Ethiopians (1). Importantly, the mean height and weight of the 30 runners (29 Africans) who have broken 27 minutes for 10,000 m is `170± 6 cm, and 56±5 kg, with only one runner greater than 178 cm or 70 kg (12)."
which cites this: "Chris Solinsky Is The Tallest And Heaviest Sub-27 Man In History"