Mezue ahịrịokwu na-esonụ: Ná mmalite afọ ndị 1970, Walker gara Mahadum Oregon ebe ọ natara ntụziaka site n'aka onye ama ama Steve Prefontaine. Mgbe Prefontaine nwụsịrị, ya na enyi ya nwanyị na nwanne ya nwanyị biri n'ụlọ ya. Walker nọchitere anya United States na 1972 International Cross Country Championships, ebe o tinyere 9th na-emeri ọla ọcha na ndị otu US, na ndị na-agba ọsọ na-agba ọsọ.
1973 IAAF World Cross Country Championships, na-emeri ndị otu ọla nchara na onye nke 30 ebe, na bụ ihe All-American na cross mba na 1973. Site na 1972 ruo 1978, o meriri Oregon Road Runners Club ụmụ nwanyị aquathlon, a biathlon nke gụnyere ịgba ọsọ na igwu mmiri, ugboro isii na-esote. N'afọ 1981, Walker laghachiri kọleji na Mahadum Oregon State ebe Joe Fulton zụrụ ya nwa oge. N'ebe ahụ, o setịpụrụ ihe ndekọ ụlọ akwụkwọ n'ọsọ ụkwụ 5,000 na 10,000. Walker bụkwa onye mmeri nke steeti Oregon n'egwuregwu triathlon na 1984, 1986, na 1987. Mmerụ ahụ ya na ụdị ọzụzụ ya na-eme ka ọ ghara ịgba ọsọ marathon ọzọ. Maka ihe ndị ọ rụzuru, a nabatara Walker n'ụlọ ezumezu ndị Portland Interscholastic League na 2005.