Negative Splits? wrote:
The superhuman closing speed in an event known to humble you in the 2nd half is a red flag. I looked up some of Kiptum’s splits from previous half marathons to see if he demonstrated any crazy negative splits and found quite the opposite.
2020 Valencia HM: Kiptum finished 6th in 58:52, over a minute behind the lead pack consisting of Kandie, Kiplimo, and Kipruto who dropped him with miles left to run. 5k splits were 13:38, 13:47, 14:06, 14:12.
2021 Valencia HM: Kiptum finished 8th in 59:02 with a similar positive split. 5k splits were 13:45. 13:50, 13:47, 14:23.
While both are certainly very quick times, nothing about these performances reflects the superhuman feat of dropping a sub-14 5k late in a marathon.
It is clear he went from a good athlete in 2018-21 to a transcendent one in 2022-present. He is young, and it seems like he started working more with a coach and putting in incredible volume. He also had a training partner Kenneth Kipkemoi absent (beta blocker doping ban) so maybe once that athlete returned in 2022 that was a boon to his training for a guy who did much of his training alone. Again, drugs could of course come into the picture but all we can say is he is in the AIU RTP and has been for some time.