NCS acting General Secretary Patrick Ogwel thanked the ambassador for laying a great foundation for team Uganda who will be like home at the games.
Returning from a knee injury, Cheptegei easily took on the race.
Here is a list of the last 10 men's world records for the marathon.
Joseph Kiprono was leading a half-marathon in Colombia.
It was the largest single improvement on the marathon world record since Derek Clayton improved the mark by 2:23 in 1967.
Diack was head of the governing body of global athletics from 1999 until his arrest in France in 2015.
Semenya beat Nakaayi at the annual ISTAF athletics meet in Berlin, Germany.
Okeyo had been provisionally suspended by the IAAF in November 2015.
He shifted his training from Namboole stadium to Uganda Christian University’s murram track.
The laboratory, due to open next month, will test all doping cases in international track and field in Kenya, Ethiopia, Eritrea, Tanzania and Uganda.
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