4 ms·

Correct, but this is so rare that can be ignored.

by acvny 6y ago

Grimm1 6y ago
Huh what? Any high muscle athletic person would hit this.
- bjo590 6y ago
  What percentage of males in the US with a BMI over 30 (obese) have a body fat percentage less than 25? My guess is less than 3%, but I don't have data to back it up. When studying populations you can ignore these outliers. It's well known that BMI works well for populations but can fail when looking at individual health.
  - codyswann 6y ago
    Checking in - MBI over 30. Body Fat Percentage less than 10. It's not rare in my circles
    - NeutronStar 6y ago
      And your circles account for how much of the population would you guess?
    - kossTKR 6y ago
      Really, 10% body fat with 30+ BMI? Without steroids, that sounds completely bonkers to me.. Can you link me a picture of a natural body that looks like yours, i'm pretty intrigued.
    - nradov 6y ago
      The point is that individuals with high BMI and low body fat are rare in the general population, and can be ignored as statistical noise in most broad scientific studies. Your circles would only be relevant for studies specifically targeting body builders.
      - Grimm1 6y ago
        They're not though, what? I want to see you back up this claim with evidence before passing it off as fact. Edit: It is fairly easy to be < 25% body fat with normal musculature that accompanies normal weight lifting and cardio routines 4 times a week. That will get you to a BMI +30 at 5"10 +
      - Nzen 6y ago
        What's the concentration of high-BMI-with-low-body fat in the general population ? Armed with that, I'll choose a p value myself, as to whether it's rare. Anecdotally, I agree, but I can't be sure that I am in contact with a represeentative sample.
  - Grimm1 6y ago
    Care to back it up I dispute that this is in fact rare. Edit:I counter with anyone who lifts and play sports and is 5" 10'+ will hit < 25% body fat and a bmi +30. You only need to be 225 pounds and at 6" 1' to be bmi +30 at 5" 10' that's only 210. I saw that fairly regularly (or at least I did precovid) at the gym.
    - bjo590 6y ago
      > I saw that fairly regularly (or at least I did precovid) at the gym. Yeah, I saw (pre-covid) it all the time at the gym, at amateur sports leagues, and at health food stores. It's also worth noting that my zipcode also has a significantly lower obesity rate than the national average. If I were to go to an Alabama Walmart the fit & muscular people people would be much more uncommon. https://www.cdc.gov/obesity/data/prevalence-maps.html https://www.cdc.gov/obesity/data/prevalence-maps.html
- fortran77 6y ago
  "The Rock" is Height 6′ 5″, Weight 260 lbs That's a BMI of 30.8 which put him on the bottom of the "obese" range. (Obese starts at 30). Obviously he's not obese. But most people who claim that they "BMI Doesn't apply to me" even though their BMI is over 30 don't look like The Rock. And he _just_ hits the obese range! If you're not an elite professional bodybuilder or weightlifter (i.e., you don't look like The Rock) BMI is probably a very good rule-of-thumb.
  - csa 6y ago
    That’s an extreme example — he’s on the very lean side in terms of body fat %. A quick google search has him at ~10% body fat and 6’3” 236 lbs. That means his lean body mass is 212 lbs. So he could gain ~21 lbs and still be squarely in the average range of body fat (20%). Tack on 8-10 lbs more for the high end of average (24%). With the 20% number, his weight would be 257 —- that’s squarely in the BMI obese category for someone who is 6’3”. The BMI numbers are just not useful for folks with a relatively high amount of lean body mass for their height. One does not need to be a body builder or gym rat to meet this criterion. A small amount of body-weight exercises plus cardio is enough for people who build muscle easily (it’s not that rare). As others have said, BMI can be useful for measuring trends in populations, but some people get carried away when using it on individuals.
    - fortran77 6y ago
      I don't think the average gym rat would have a BMI in the "obese" range (maybe overweight) unless they start getting into "Rock" territory. That was my point. I'm a "gym rat" (I'm the co-owner of a gym). Lift weights every day. I look athletic. I'm 5'10" 170#. That's a BMI of 24. Not even in the "overweight" range. Most people who say "BMI is meaningless/unfair/outdated" aren't in the group of people who outliers. It is a very good quick check, especially for considering the characteristics of a population when looking for correlations (like obesity vs cognitive ability, or obesity vs Type II diabetes). Doctors tend to record height and weight of patients with reasonable accuracy. Even doing other measurements like hip/waist ratio are a bit subjective (where, exactly is the waist. Where are the hips--especially on an obese subject. How "tight" are you holding the tape measure?) BMI eliminates those subjective elements.
csa 6y ago
For fast twitch people who exercise, it’s not that rare.

Correct, but this is so rare that can be ignored.

by acvny 6y ago

Correct, but this is so rare that can be ignored.

Grimm1 6y ago

Huh what? Any high muscle athletic person would hit this.

bjo590 6y ago
What percentage of males in the US with a BMI over 30 (obese) have a body fat percentage less than 25? My guess is less than 3%, but I don't have data to back it up. When studying populations you can ignore these outliers. It's well known that BMI works well for populations but can fail when looking at individual health.
- codyswann 6y ago
  Checking in - MBI over 30. Body Fat Percentage less than 10. It's not rare in my circles
  - NeutronStar 6y ago
    And your circles account for how much of the population would you guess?
  - kossTKR 6y ago
    Really, 10% body fat with 30+ BMI? Without steroids, that sounds completely bonkers to me.. Can you link me a picture of a natural body that looks like yours, i'm pretty intrigued.
  - nradov 6y ago
    The point is that individuals with high BMI and low body fat are rare in the general population, and can be ignored as statistical noise in most broad scientific studies. Your circles would only be relevant for studies specifically targeting body builders.
    - Grimm1 6y ago
      They're not though, what? I want to see you back up this claim with evidence before passing it off as fact. Edit: It is fairly easy to be < 25% body fat with normal musculature that accompanies normal weight lifting and cardio routines 4 times a week. That will get you to a BMI +30 at 5"10 +
    - Nzen 6y ago
      What's the concentration of high-BMI-with-low-body fat in the general population ? Armed with that, I'll choose a p value myself, as to whether it's rare. Anecdotally, I agree, but I can't be sure that I am in contact with a represeentative sample.
- Grimm1 6y ago
  Care to back it up I dispute that this is in fact rare. Edit:I counter with anyone who lifts and play sports and is 5" 10'+ will hit < 25% body fat and a bmi +30. You only need to be 225 pounds and at 6" 1' to be bmi +30 at 5" 10' that's only 210. I saw that fairly regularly (or at least I did precovid) at the gym.
  - bjo590 6y ago
    > I saw that fairly regularly (or at least I did precovid) at the gym. Yeah, I saw (pre-covid) it all the time at the gym, at amateur sports leagues, and at health food stores. It's also worth noting that my zipcode also has a significantly lower obesity rate than the national average. If I were to go to an Alabama Walmart the fit & muscular people people would be much more uncommon. https://www.cdc.gov/obesity/data/prevalence-maps.html https://www.cdc.gov/obesity/data/prevalence-maps.html
fortran77 6y ago
"The Rock" is Height 6′ 5″, Weight 260 lbs That's a BMI of 30.8 which put him on the bottom of the "obese" range. (Obese starts at 30). Obviously he's not obese. But most people who claim that they "BMI Doesn't apply to me" even though their BMI is over 30 don't look like The Rock. And he _just_ hits the obese range! If you're not an elite professional bodybuilder or weightlifter (i.e., you don't look like The Rock) BMI is probably a very good rule-of-thumb.
- csa 6y ago
  That’s an extreme example — he’s on the very lean side in terms of body fat %. A quick google search has him at ~10% body fat and 6’3” 236 lbs. That means his lean body mass is 212 lbs. So he could gain ~21 lbs and still be squarely in the average range of body fat (20%). Tack on 8-10 lbs more for the high end of average (24%). With the 20% number, his weight would be 257 —- that’s squarely in the BMI obese category for someone who is 6’3”. The BMI numbers are just not useful for folks with a relatively high amount of lean body mass for their height. One does not need to be a body builder or gym rat to meet this criterion. A small amount of body-weight exercises plus cardio is enough for people who build muscle easily (it’s not that rare). As others have said, BMI can be useful for measuring trends in populations, but some people get carried away when using it on individuals.
  - fortran77 6y ago
    I don't think the average gym rat would have a BMI in the "obese" range (maybe overweight) unless they start getting into "Rock" territory. That was my point. I'm a "gym rat" (I'm the co-owner of a gym). Lift weights every day. I look athletic. I'm 5'10" 170#. That's a BMI of 24. Not even in the "overweight" range. Most people who say "BMI is meaningless/unfair/outdated" aren't in the group of people who outliers. It is a very good quick check, especially for considering the characteristics of a population when looking for correlations (like obesity vs cognitive ability, or obesity vs Type II diabetes). Doctors tend to record height and weight of patients with reasonable accuracy. Even doing other measurements like hip/waist ratio are a bit subjective (where, exactly is the waist. Where are the hips--especially on an obese subject. How "tight" are you holding the tape measure?) BMI eliminates those subjective elements.

csa 6y ago

For fast twitch people who exercise, it’s not that rare.