Get a four-wheel, high quality folding roller cart with at least 6" wheels. Then keep it oiled and maintained. Use your arms and legs to move it around for shopping
; and use local transport for touring as you'll meet lots more locals this way. My experience cruising favored this strategy over small folding bikes, etc.
[BTW, the obesity epidemic started about 75 years after Mr. Ford's automotive innovation and it pretty much coincided with "the Big Mac" revolution in eating. The cause of obesity is diet and the quality of the food
on the shelf, not lack of exercise.]