Exercise, good food, and good sleep. Pretty much the universal panacea.

Sounds easy, but difficult in practice. Especially for those of us chained to a desk all day.

Mild to moderate exercise won't fix it, but intense exercise, e.g. running or similar, carries hope. Good sleep will slow the damage, but after a certain age, e.g. 80, it may not work.

What about a hard workout with weights every day?

I have tried it in this context, but no, I'm sorry. Only running and similar intense cardio exercises had an applicable effect for me. That's not to say that other exercises are useless; obviously they're not, but the other exercises didn't help this particular issue for me.

That might set you up for overtraining. If your ability to regenerate is good/fast enough, it might work. Measuring heart rate variability is a good indicator for when you’re ready for more exercise.

Cardio specifically, right?

All of it is ultimately needed. Cardio, yes, but resistance training is also needed to maintain muscle mass, and maybe even more important as we age, bone density.

For disabled and elderly people, these aren't always possible.

Appropriate exercise is all the more important for disabled and elderly people.

Lymphatic massage should help. It has helped my recurring ear issues tremendously, and is actually quick and easy to do. There are plenty of YouTube videos out there, some for the whole body and some for the face/neck area.

Here is a short video for the back of the neck: https://bornfree.life/images/neck-lymphatic.mov

Nafaik, but anything that gives you two extra hours of sleep should help. Also, intense exercise should over time help heal it in part. And as far as drug methods go, a 2-3 month course of memantine could be worth exploring for anyone who doesn't have to drive or operate machinery for the first month.

Probably tai chi or qigong as well.

I’m convinced we are going to discover that “qi work” is moving lymph through the connective tissue (a phenomenon we only just discovered a decade ago). The proscriptions against doing these exercises or massage during an illness is my clue/circumstantial evidence and I hope it gets studied more.