Whakakihia te rerenga e whai ake nei: Ko te tīmatanga o Niyonkuru i tētahi whakataetae ao whānui i te
Ko te 2005 IAAF World Cross Country Championships. I whakataetae ia i te whakataetae a nga taane rangatahi ka mutu i te 33 o nga kaitakaro 133 i roto i te waa 25 meneti me te 32 hēkona. I te 2005 Jeux de la Francophonie Niyonkuru i whakataetae i te 10,000 mita. I mutu a Niyonkuru i te tuawha i roto i te waa 29 meneti me te 18.08 hēkona, 0.03 hēkona noa iho i muri i te toa hiriwa, Moroccan Abderrahim Goumri. I whakataetae a Niyonkuru i te 2006 World Junior Championships. I oti ia i te tuarima i te 10,000 mita i te wa o te 28 meneti me te 59.92 hēkona. I 6.63 hēkona ia i muri i te toa o te whakataetae, a Ibrahim Jeilan o Etiopia. I te 2007, i whakataetae a Niyonkuru i te 2007 World Cross Country Championships i te whakataetae a nga taane rangatahi. I oti ia i te 13 i roto i te 24 meneti me te 56 hēkona. I oti ia i te 49 hēkona i muri i te toa koura, te Kenyan Asbel Kiprop. I te 2009 World Military Track and Field Championships, i wikitoria a Niyonkuru i te mētara hiriwa i te 10,000 mita. Ko tana wa 29 meneti me te 37.14 hēkona he 23.67 hēkona i muri i te toa koura, a Essa Ismail Rashed o Qatar. I 4.97 hēkona a Niyonkuru i mua o te toa parahi, o Tunisian El Akhdar Hachani. I wikitoria a Niyonkuru i te 2015 Auray-Vannes Half Marathon i te wa kotahi haora, e toru meneti me te rua tekau hēkona. I nga Taakaro Orimipia o te Raumati 2016, i whakataetae a Niyonkuru i te marathon a nga taane i te 21 Akuhata 2016, engari kaore i oti te whakataetae. I te tau 2017 i whakataetae ia i te marathon a nga taane i te 2017 World Championships in Athletics, i tuu i te 71, i te 2:42:27.