[hellbender]

Congratulations! However, I would strongly encourage you to lose weight. As I said, I don't see any old obese hikers. Either they do not survive to old age, or the overload on their joints wears out their cartilage prematurely. It is well known that obesity is correlated with deterioration of knees. I was shocked to learn that it is also associated with arthritis of the hands, which I have.

What is the elevation you started out at on Mt. Rainier? I find that elevation gain is the main determinant of how strenous a hike is. Also, 8600' is higher than anything in this part of the country, and the air is thinner, making any exercise harder.

[irishtenor]

To be perfectly honest, my ideal weight (determined by three separate tests) is 215-220 pounds, due to the density of my bones and muscles. And my thick skull, of course. I am slowly losing, and should be there by next spring.
As for Mt Rainier, the parking lot is at about 4800 ft. meaning almost 4000 ft elevation gain in 4 miles. It is not a simple climb. The entire climb was in knee deep snow.

I did Mt Si twice, Squak Mountain and Tiger Mountain and several times up Rattlesnake Ledge before we climbed Rainier. Next year I will summit!
You can look those climbs up on the internet.