John Smith:
Walk casually around your home for about two or three miles thrice a week to build up your body resilience and optimizing your stamina.
With respect, when standing and walking without pain is an issue, 2-3miles is probably completely out of the question.
I’ve been in a similar position recently, albeit not as extreme, and I also have asthma. Here’s what I’ve done that made an almost immediate improvement of my breathing, strength, and mobility:
1. If you smoke, switch to vaping. I was skeptical because years ago vaping made my asthma worse, but I think the market for liquids has gotten a lot better since the early 2010’s 😅
2. Switch to zero and low calorie drinks. This has not only kept my blood sugar under control, but helped me lose 1/2 a stone when I really needed to lighten the strain from gaining too much, too fast. I also hate dieting, and doing this *plus making healthier food choices for 2-4 weeks* allowed to lose enough weight to make me feel lighter and stronger.
3. Learn to be conscious of your core muscles - they surround the spine and control your balance and, in my experience, you really have to gain those muscles intentionally, although not necessarily by “working out”! Forgive me if I’m preaching to the choir here (you mentioned already having back issues and have probably heard this all before), but I cannot recommend standing yoga enough! You can find free videos everywhere, and maybe nowadays there are some size-friendly ones out there too 😋
4. Walking is the best thing any of us can do, but when my strength-to-fat ratio was at its worst (or best, for all you laziness lovers! 😜) , even the briefest of walks had me gasping for air and sweating like a pig. It’s okay if this is you too! There is value in simply trying to get there, if you keep on trying. Same goes for standing: I treat making tea and cooking as mini workouts where I try not to sit down and to maintain proper posture, and I do squats when I’m putting on weight (stops my knees and lower back from aching as much).
It sucks like #%*^#, I know. But don’t panic! All it took was a 5-10lb loss for me to feel like a bouncy spring chicken, compared to how I had felt before, at least. Think about suddenly having to carry a 30lb suitcase literally everywhere - you’d be exhausted, but you’d also be getting stronger from it - what I mean by that is you’re closer to feeling better than you probably think!