Sagetown
Farmer and a STIHL
When I joined I was 18. I could run 7 minute miles all day long, biked 40-80 miles a week(I had an awesome Pinarello back then), and took 3-6 hours of ju jutsu and karate a week. This all prepared me for working in the Sierras, but none of them even came remotely close to even making my first day comfortable. I thought for certain I was gonna die on the side of the mountain back then. My feet were literally bleeding the first week. And I was thirsty from dawn to sleep. The pack test just weeds out those that have no reason being in a crew. Cardio and endurance are important, but I would prepare for fire fighting by hiking up long trails with alot of elevation on them in heavy boots. Do not wear hiking shoes. I wish I had done that before I joined.
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My 1st mountain experience was at age 17 in the high Sierras in CA. Like you, I found it altogether a whole new ball game of physical fitness that I'll never forget.