I am new to hiking/backpacking but am generally fit in terms of being an ultra endurance cyclist, e.g. riding for 23 hours straight etc.
I did the hike to San Gorgonio summit (Vivian Creek trail) without too much difficulty, had a 35 lb pack just to see if I'd have difficulty with it. https://www.alltrails.com/explore/trail/us/california/vivian-creek-trail-to-san-gorgonio-peak
I'm planning to do Cactus to Clouds hike around October, and need to train for it:https://hikingguy.com/hiking-trails/best-la-hikes/cactus-to-clouds-hike/
Next to my office at work, I have a stairwell that goes up 7 stories. Is it a reasonable plan that - every other day - I go up and down that stair with a 35 lbs backpack for progressively longer times, e.g. starting at 20 minutes and up to an hour? When I hit one hour (the max I can spend on my lunch break), I'll just increase the pace so that I get huffing and sore faster.
If needed, once a month, I can go on a hike like the San Gorgonio hike mentioned above. But otherwise, I prefer to spend my weekends cycling.