Dee ihe na-aga n'ihu maka paragraf a - Egwuregwu egwuregwu nkwarụ mbụ ya bụ mgbe ọ dị afọ iri na otu, merie ọla edo asaa n'ọtụtụ ihe omume. N'afọ 2008, mgbe ọ dị afọ iri na anọ, a họpụtara ya ka ọ nọchite anya Great Britain na Summer Paralympic Games na Beijing, na-emecha nke iri na otu na ụmụ nwanyị F42-46 javelin. Ọ bụ onye kachasị na-eto eto na ndị otu Great Britain nke 2008. N'afọ na-eso ya, o nwetara ihe nrite mbụ ya dị mkpa mgbe ọ gbara asọmpi na 2009 IWAS World Junior Championship na Switzerland, na-enweta ọla ọcha na F46 diski na ọla nchara na F46 javelin. 2009 bụ afọ ikpeazụ Arnold gbara asọmpi na diski, na-elekwasị anya kpamkpam na javelin. N'afọ na-eso ya, o mere nke ọma n'ihe nrite ya na javelin mgbe o nwetara ọlaọcha na 2010 IWAS World Junior Championship wee were ọla edo na 2011 Championship nke emere na Dubai. N'afọ 2011 Arnold gbara onye isi egwuregwu na-anọchite anya Briten n'asọmpi IPC Athletics World Championships
na New Zealand; ọ bịara nke atọ na F46 javelin, were ọla nchara. N'afọ 2012, o ritere ọla ọcha na asọmpi IPC. E dekọtara nke kachasị mma ya na F46 javelin na 35.88m na June 2012 na Welsh Championship na Cardiff, na-ahọpụta ya dị ka nọmba ụwa abụọ na ihe omume ya na-aga na 2012 Paralympics. E mere ka Arnold bụrụ onye kacha mma na 2012 Summer Paralympics na London na 36.27m. Na 22 Julaị 2013, Arnold gbara asọmpi na IPC Athletics World Championships na Lyon. O ritere ọlaedo site na mmeri nke 37.45m, na-akwalite ihe ndekọ onwe ya.