RUNNING PERFORMANCE, NATIONALITY, SEX, AND AGE IN THE 10-KM, HALF-MARATHON, MARATHON, AND THE 100-KM ULTRAMARATHON IAAF 1999-2015

The aim of this study was to examine the performance of the world's best runners in the 10-km, half-marathon, marathon, and 100-km races by age, sex, and nationality during 1999-2015, using data from the International Association of Athletics Federations (IAAF). A total of 38,895 runners (17,136 women and 21,759 men) were evaluated, with 2,594 (1,360 women and 1,234 men) in the 10-km; 11,595 (5,225 women and 6,370 men) in the half-marathon; 23,973 (10,208 women and 13,765 men) in the marathon; and 733 (343 women and 390 men) in 100-km events. Most runners in the 10-km event (women 40%, men 67%) and the half-marathon (women 30%, men 57%) were Kenyans. In the marathon, most female and male runners were Ethiopians (women 17%, men 14%) and Kenyans (women 15%, men 43%), respectively. In the 100-km event, most runners were Japanese (20% women, and 80% men). Women were older than the men in the 10-km (32.0 +/- 6.0 vs. 25.3 +/- 4.3 years, p < 0.001), half-marathon (27.5 +/- 4.7 vs. 25.9 +/- 4.1 years, p < 0.001), and marathon events (29.5 +/- 5.5 vs. 29.1 +/- 4.3 years, p < 0.001), but not in 100-km event (36.6 +/- 6.1 vs. 35.9 +/- 5.5 years, p = 0.097). Men were faster than the women in the 10-km (28:04 +/- 0:17 vs. 32:08 +/- 0.31 (minutes: seconds), p < 0.001), half-marathon (1:01:58 +/- 0:00:52 vs. 1:11:21 +/- 0:01:18 (hours: minutes: seconds), p < 0.001), marathon (2:13:42 +/- 0:03: 01 vs. 2:35:04 +/- 0:05:21 (hours: minutes: seconds), p < 0.001), and 100-km events (6:48:01 +/- 0:11:29 vs. 7:53:51 +/- 0:16:37 (hours: minutes: seconds), p < 0.001). East Africans were not the fastest compared with athletes originating from other countries where only the Ethiopian men were faster than all other men in the marathon. In summary, (a) in the 10-km, half-marathon and marathon events, most runners were from Kenya and Ethiopia, and from Japan and Russia in the 100-km event; (b) women were older than the men in all distance events except the 100-km event; (c) men were the fastest in all distances; and (d) Ethiopian men were faster than all other men in the marathon.