Well, re the "medically obese" classification; my health insurance covers all kinds of weight-loss surgeries and drugs, if one is "morbidly obese", which is defined as desirable weight plus 100 lbs; or some body mass index number that doesn't quite work for my aged brain. The benchmark shifts closer to "desirable" if you have uncontrollable blood pressure, diabetes, heart attack, or stroke. Are you sure you want to go there?
About the carpal tunnel - don't assume that any particular individual will get it. Repetitive stress may trigger it, but it also requires that the carpal tunnel be insufficient to the tendons that pass through, that the cartilege swell and "stick" from the stress in the carpal tunnel, and that scarring and adhesions will eventually accumulate to the point where the whole hand ceases to work properly or comfortably.
I've been typing regularly since, ah, well, 1959. My mother couldn't read my handwriting and bought me a typewriter and signed me up for a summer school class. That manual typewriter was an old office model Royal, had really stiff key springs, and when you switched to upper case you had to lift the carriage half an inch up with your little finger.
My hobbies are all fiddly little handwork things (quilting, other sewing, knitting) except for the reading and cooking things. I spend most of each workday on a computer keyboard, and I also use the computer at home for other hobbies (BBB, e-mail, solitaire). My sister's hobbies are similar - she spins, she knits more, quilts and sews much less. We both read. She keyboards less.
She's had carpal tunnel surgeries. Plural. Multiple. I haven't. No explanation. No lifestyle differences worth mentioning. She's a little younger. She has two children, I have three. She's more a type A personality, I'm more a type B. She's more active, I'm more sedentary. She's a better housekeeper, I'm a better cook. Her hands hurt. Mine don't.