Here are some facts about the top 5 of these two countries, comparing pre- and post-super shoes in the last decade, with the latter coinciding with the increased testing in Kenya:
Average top 5 marathoners:
2010 – 2014: Kenya 2:03:28; Ethiopia 2:04:37
2015 – 2019: Kenya 2:03:24; Ethiopia 2:02:51
The Kenyans only improved by 4 seconds, the Ethiopians by a whopping 106 seconds.
Also, each of the top 10 (!) Ethiopians was faster with supershoes than their top runner pre-super shoes, while that is true only for one Kenyan.
In detail:
Kenyan top marathon performers, 2010 – 2014
2:02:57 – Kimetto Berlin 2014
2:03:13 – Mutai Berlin 2014
2:03:23 – Kipsang Berlin 2013* – banned 2020
2:03:38 – Makau Berlin 2011
2:04:11 – Kipchoge Chicago 2014
Average: 2:03:28 (1x 2:02, 3x 2:03, 1x 2:04)
Kenyan top marathon performers, 2015 – 2019
2:01:39 – Kipchoge Berlin 2018
2:03:13 – Kipsang Berlin 2016 – banned 2020
2:03:51 – Biwott London 2016
2:04:06 – Cherono Amsterdam 2018 – banned 2022
2:04:11 – Kipserem Rotterdam 2019 – banned 2022
Average 2:03:24 (1x 2:01, 2x 2:03, 2x 2:04)
Ethiopian top marathon performers, 2010 – 2014
2:04:23 – Abshero Dubai 2012
2:04:32 – Mekonnen Dubai 2012
2:04:38 – Kebede Chicago 2012
2:04:45 – Desisa Dubai 2013
2:04:48 – Tsegay Rotterdam 2013
Ave: 2:04:37 (5x 2:04)
2015 – 2019
2:01:41 – Bekele Berlin 2019
2:02:48 – Legese Berlin 2019
2:02:55 – Geremew London 2019
2:03:16 – Wasihun London 2019
2:03:34 – Molla Dubai 2019
Ave: 2:02:51 (1x 2:01, 2x 2:02, 2x 2:03)