Your fitness level really affects how much activity you find tiring. I remember back when I was a teenager working at a grocery store I freaked out because I saw a woman dripping with sweat and panting (I was worried it was a heart attack or other medical emergency) and she explained that she’s fine, she just decided to walk her shopping instead of getting a motorized cart today.

Or for a more personal anecdote, I got on my bike for the first time in a decade early last spring and barely made it one block on the bike before being at the nearly-vomitimg-from-over-excersion point then by biking every day I got up to biking 8 miles a ride by the end of fall

You don’t have to be tired for it to be exercise

OOP did mention chronic pain, so to them it probably is.

when you spend most of your time in a relatively sedentary lifestyle, walking a mile can be a lot of exercise. for someone who wants a minimum of 12,000 steps a day, it seems like nothing, but for someone who averages maybe 1000 steps, it can take a lot of physical and/or mental effort. especially if that person is dealing with chronic pain or depression

Yeah, same. Its remarkable tbh