I'm wondering if maybe it's harder to get to the 4000 calorie mark than it seems. I actually don't know how many calories I burn. But I might ride my bike to work (18 miles round trip), run for an hour at lunch or do an exercise class, either doing one or the other or both each day of the work week, then one nice long hike, often pretty strenuous, on the weekend. And one rest day. I suppose you can toss out the bike ride and the run, since I go so very slowly on both, and therefore my exercise class and my strenuous hike are the only two activities that could be considered in the 4000 calorie equation, and maybe not the exercise class since it's all body weight stuff. So I guess I'm okay. But I'm telling you, when I hiked the PCT I hiked 14 hours a day in high summer and I knew it was a little bit too much for ideal health, but I did feel awesome being able to do it.
Female, 5'3", 48, Starting weight: 163lbs. Current weight: 135.
Starting squat: 45lbs. Current squat: 145 x 4.