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I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

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Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#231

Post by terribleperson »

ltbarcly3 wrote: post #170
terribleperson wrote: post #54

Earlier quoted context omitted.

Do you have a custom prompt/personality set? What is it?

Yea, if only he had said "make sure you are always honest" first!

It's not that you need to ask it to be honest, it's that the defaults are kind of stupid and obnoxiously sycophantic. ChatGPT is also prone to getting stuck on particular ideas. If you're using the vanilla personalities without a custom prompt, not aware of and working against its issues, and not starting new chats occasionally you won't get good results. You'll get good-sounding garbage.

Part of my custom prompt is ```When using factual information beyond what I provide, verify it when possible. When researching factual questions—especially by relying on papers and studies—actively look for null findings, negative results, and contradictory evidence, not just positive or confirmatory findings.```

To me, the most interesting result of that part of my prompt is that in thinking mode, it ends up re-checking it's assumptions and sources fairly often. It's not about honesty, but correctness.

A custom prompt isn't the be-all end-all either. The right kind of questioning is important, and you also need to get a fresh context when you ask new questions or if you want to double check something.

Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#232

Post by port11 »

smcl wrote: post #215
port11 wrote: post #204

Earlier quoted context omitted.

I really don’t know whether to trust that specific measurement. When I was a very active runner and doing intervals to improve per-km time, my VO2max went from 38 to 42. I decided to do a professional VO2max test and got a 46. Now, 2 years later, I don’t run due to injury and a kid, and it’s resting at 34. For reference, when I went to the gym almost everyday and ran once or twice a week, the value was 32. I don’t ge…

Yeah so I know it's meant to be an estimate, but my experience of it is kinda fucky. I would really love to swap watches with an Olympic athlete (idk if they'd bother with an Apple Watch but bear with me!) and run 10k to see what the VO2 max reading for that exercise was. As I said, I think to me it's some estimate that heavily involves some "average of last N readings from the Apple VO2 max calc" function so even if…

That experiment might be unfruitful because I assume Apple’s algorithm was not trained on outliers. Very capable athletes might see similarly silly data because they don’t fit well into the bell curve. Maybe.

Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#233

Post by machomaster »

jermaustin1 wrote: post #205
sotix wrote: post #198

Earlier quoted context omitted.

I'd consider 5'8 and 210lbs morbidly obese. An average male at 5'8 should generally weigh about 150lbs and no more than 164lbs.

If I got rid of all of my fat and bones, I'd still weigh more than 150lbs. I have the most muscular 150lbs man inside of me. Ideal body fat percentage is 18-24% - I'm at 25% (or was in November - might be +/- 2% since then - gained a few pounds weight, but not waist size). So I would say I'm not morbidly obese or even regular obese based on the percentage of my body that is muscle vs fat.

You are fat, though. For a man, the ideal fat percentage is 15-20%. 20+%, let alone 25%, is not healthy at all.

Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#234

Post by machomaster »

colechristensen wrote: post #183
steveBK123 wrote: post #130

Earlier quoted context omitted.

It’s also cultural. Most American doctors don’t bother to tell people if they are overweight and out of shape. It’s not something their customers reward.

I mean... most people already know, it's not like either of those things come as a surprise to anybody.

Most obese people think "I am a bit on a heavy side, but I am not that fat and definitely not obese".

People are generally in denial about their fat percentage and their muscle mass. Even somewhat healthy people (~20% fat) who are calculating how much they must lose in order to get to a healthy 12-15%, are surprised when the reality shows that they calculations were 5-15kg off.

Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#235

Post by steveBK123 »

machomaster wrote: post #234
colechristensen wrote: post #183

Earlier quoted context omitted.

I mean... most people already know, it's not like either of those things come as a surprise to anybody.

Most obese people think "I am a bit on a heavy side, but I am not that fat and definitely not obese". People are generally in denial about their fat percentage and their muscle mass. Even somewhat healthy people (~20% fat) who are calculating how much they must lose in order to get to a healthy 12-15%, are surprised when the reality shows that they calculations were 5-15kg off.

Most people are wrong about their body type, in the wrong direction (overweight think they aren't that overweight, skinny think they need to lose weight).

Having an objective voice from your doctor giving you annual feedback and suggestions is better than ignoring the topic entirely.

Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#236

Post by seemaze »

meindnoch wrote: post #119
seemaze wrote: post #23

I can't wait until it starts recommending signing me up for an OpenAI personalized multi-vitamin® supscription

"You're absolutely right! I was mistaken about mercury and lead being essential minerals, and adding them to your supplements. Sorry about that!"

I was casually browsing for a heath monitor when I came across Ultrahuman Blood Vision - one of the key features being AI Clinical Summary with Supplement Report.. it seems my sarcasm was late to the party.

Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#237

Post by firmretention »

csa wrote: post #214
sotix wrote: post #198

Earlier quoted context omitted.

I'd consider 5'8 and 210lbs morbidly obese. An average male at 5'8 should generally weigh about 150lbs and no more than 164lbs.

> I'd consider 5'8 and 210lbs morbidly obese. An average male at 5'8 should generally weigh about 150lbs and no more than 164lbs You would consider incorrectly then. This person has ~155 pounds of lean body mass . 164 would put him at roughly a body builder level of fat, which basically requires a part time job in cooking and nutrition to maintain. For reference, I’m in a similar situation to this person. I’m 5’11” (…

Dexas are notoriously inaccurate. Your dexa scan is probably wrong, and you are fatter than you think. I've been lifting over a decade, so I have far more muscle mass than the average person, and I am 6'1", yet am still easily over 20% BF if I'm 200 lbs or more. Don't believe me? Try to get truly shredded. You'll see for yourself that you will have to lose far more weight than you think. Everyone is fatter and less muscular than they think they are, even if they're active. Unless of course you are a heavy steroid user, in which case you may actually be muscular enough for that to be valid. But for the average natural trainee? Nobody who's truly lean is getting an obese or morbidly obese BMI. Overweight at worst, maybe.

BMI is definitely inaccurate for those with greater amounts of muscle mass, but not as inaccurate as many would like to believe.

Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#238

Post by colechristensen »

machomaster wrote: post #234
colechristensen wrote: post #183

Earlier quoted context omitted.

I mean... most people already know, it's not like either of those things come as a surprise to anybody.

Most obese people think "I am a bit on a heavy side, but I am not that fat and definitely not obese". People are generally in denial about their fat percentage and their muscle mass. Even somewhat healthy people (~20% fat) who are calculating how much they must lose in order to get to a healthy 12-15%, are surprised when the reality shows that they calculations were 5-15kg off.

that's gym bro science, there's no compelling health reason to lower your fat percentage to 12-15% and it carries as much risk as being rather obese when accounting for all causes mortality, particularly for women and people getting older

Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#239

Post by csa »

firmretention wrote: post #237
csa wrote: post #214

Earlier quoted context omitted.

> I'd consider 5'8 and 210lbs morbidly obese. An average male at 5'8 should generally weigh about 150lbs and no more than 164lbs You would consider incorrectly then. This person has ~155 pounds of lean body mass . 164 would put him at roughly a body builder level of fat, which basically requires a part time job in cooking and nutrition to maintain. For reference, I’m in a similar situation to this person. I’m 5’11” (…

Dexas are notoriously inaccurate. Your dexa scan is probably wrong, and you are fatter than you think. I've been lifting over a decade, so I have far more muscle mass than the average person, and I am 6'1", yet am still easily over 20% BF if I'm 200 lbs or more. Don't believe me? Try to get truly shredded. You'll see for yourself that you will have to lose far more weight than you think. Everyone is fatter and less m…

I didn’t want to belabor the point in my original post, but since you went there…

The next steps at the doctor is that I show them my MyFitnessPal nutrition tracking, my dexascan, and (at some point) take off my shirt. I ask them what exactly it is I should change. 100% of the time the answer has been something like “Oh, sorry. Please continue as you are doing.”

They just aren’t used to seeing muscular 200 pound dudes at my height in my area at my age (btw, I’m in my 50s).

Also, someone can workout in the gym all they want, but I think most people will struggle with lowering their body fat percentage if they don’t focus on their nutrition.

I realize that my lean body mass (both bones and muscle) are decreasing, and that rate of decrease be higher each year. That said, I’m doing what I can to maintain whatever muscle and bone mass I have.

Re: I let ChatGPT analyze a decade of my Apple Watch data, then I called my doctor

#240

Post by friendzis »

FeteCommuniste wrote: post #124
inopinatus wrote: post #100

Earlier quoted context omitted.

Many of those metrics are population or sampling measures and are confounded by many factors at an individual level. The most notorious of which is BMI; it is practically a category error to infer someone's health or risk by individual BMI, and yet doing so remains widespread amongst people that are supposed to know better. Instrumentation and testing become primarily useful at an individual level to explain or inves…

> The most notorious of which is BMI; it is practically a category error to infer someone's health or risk by individual BMI, and yet doing so remains widespread amongst people that are supposed to know better. BMI works fine for people who aren't very muscular, which is the great majority of people. Waist to height ratio might be more informative for people with higher muscle mass.

No. BMI does not work as a diagnostic measure for general population. The range of "normal" BMI values does depend at least on genetic lineage, gender and individual development history. Fine to compare two scandinavian lineage men, but if you compare e.g. a dutch man with an african woman oh boy, you error margins would be mid-to-high single digit units

> Waist to height ratio

Again, while not a bad metric per se, translates poorly between cohorts.

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