Mezue ahịrịokwu na-esonụ: Ná mmalite nke ọrụ ya, Nielsen zụrụ ọzụzụ na Finland, nke bụ mba na-eduga n'ịgba ọsọ ogologo oge n'oge ahụ, ma mụta ihe n'aka ndị na-agba ọsọ Finnish. O meriri aha mbụ ya na Danish Championship na 5000 m na 1930. Nielsen mebiri ihe ndekọ ụwa nke 3000 m na Stockholm na 25 Julaị 1934; o chere Polish Janusz Kusociński, onye nwere ndekọ gara aga nke 8:18.8, ihu ma merie ya. Oge Nielsen meriri bụ 8:18.3; dị ka ihe ndekọ ụwa, a kwadoro ya dịka 8:18.4, ebe ọ bụ na iwu nke IAAF chọrọ ka oge dị anya na-agbakọta ruo na ise nke abụọ. N'afọ ahụ, Nielsen meriri ọla nchara n'ọsọ 10,000 m n'asọmpi mmeghe.
European Championships na Turin, na-efunahụ naanị Ilmari Salminen na Arvo Askola nke Finland; ọ bụ naanị onye nrite nke Denmark na nzukọ ahụ.