Body Mass Index



  • Is the Body Mass Index something to tell you if you're overweight? I'm very sceptical of a BMI because it doesn't seem to take into account people's  body shape or build, nor does it seem to take into account how much muscle someone has. For example, the BMI of most top class props would say that they are overweight, even if they've got bugger all fat on them.

    For those interested, you can calculate your BMI by dividing your weight in kgs, by your height in metres, squared. Apparently, a BMI over 25 is overweight, and a BMI of over 30 is obese? So thus, my BMI has pretty much always shown me to be overweight, even when I was playing full-on school or club footy and training like a fucking psycho.

    Sounds like bullshit. Can someone explain it to us?



  • There are charts that doctors have had for years which measure developmental growth for children, and also average height/weight for adults. These things are a guide only and yes if you've got the skeletal structure of some form of human/rhino cross then BMI often isn't much use for you. If you're lean like a distance runner it will also feed you bullshit.

    My height is 180cm and my weight is 118kg. My BMI is therefore about 36 so technically I'm obese, but I'd actually put myself on the borderline between obese and overweight. I know I'm overweight but its not all fat - I have a huge skull (getting the aircraft warning light put in next week) and fairly broad skeletal structure so I'll probably always be overweight.

    Even if I reach a perfectly suitable goal weight of 100kg and can run around like a mad bastard all day, the BMI calculator still has me at nearly 31. To get back under BMI=25, I'd have to 81kg and that is 37kg away



  • same height here pretty much NTA, and at 105kgs.  so should be what, 2.15 metres tall or something to be the right weight.  Basically a pile of shit.



  • excellent thanks lads....I thought it was shit, just needed confirmation.

    [quote name='Nick the Aussie'] My height is 180cm and my weight is 118kg. My BMI is therefore about 36 so technically I'm obese, but I'd actually put myself on the borderline between obese and overweight. I know I'm overweight but its not all fat - I have a huge skull (getting the aircraft warning light put in next week) and fairly broad skeletal structure so I'll probably always be overweight.

    Even if I reach a perfectly suitable goal weight of 100kg and can run around like a mad bastard all day, the BMI calculator still has me at nearly 31. To get back under BMI=25, I'd have to 81kg and that is 37kg away
    [/quote]

    For some reason I thought you were taller than that Nick? Were you standing on a box in your wedding photos? 😁 You looked about 6'3 in those pics I reckon.

    Yeah, well I'm 187cm and 99 kg which puts me at 28...still overweight. But if BMI's are bullshit then I'll just ignore it. :coolsmiley:



  • If the BMI was correct then almost all International rugby forwards would be counted as being morbidly obese.  The BMI doesnt take into account bodyfat or muscle mass which is just as well in my case!



  • My scales have some sort of body fat monitoring device, calculated using your weight, height and some electrical pulses that it sends through your body. When I saw them in the shop, I had to have them because it sounded like such crap.

    Anyway, my healthy body fat range is, apparently, 8% to 20%. This evening I registered 36.4%Â



  • those things are bollocks!  I was woring in a pharmacy once, doing the one hour photo lab ting, and would work nights to get the next day photos sorted.  ANyway, boring as fuck, so one night used them, drank about three litres of water, jumped on, and my BF had gone up, and all it was was water, obviously.  So a load of shit...Â

    Aren't they...?



  • [quote name='BartMan']
    those things are bollocks!  [/quote]

    MvJ certainly hopes so; classic "as seen on TV" infomercial kind of product.



  • Yeah I would have to lose nearly 30% of my bodyweight to not be overweight and while I won't quibble with obese (120kg's 1.89m) if I was there target weight I'd slip through cracks in the footpath and unlike you guys I'm not carrying loads of muscle.



  • [quote name='Red Bull']
    For some reason I thought you were taller than that Nick? Were you standing on a box in your wedding photos? 😁 You looked about 6'3 in those pics I reckon.[/quote]

    Yeah thanks Mrs the Aussie isn't the tallest girl in the world  but I likes em small I does :twisted:

    The electric pulses for body fat are no real indicator. They can be wildly inaccurate depending on how much you sweat, how hyrdated you are, and whether you're standing on the precise points for them. Body pinch is the only way.



  • BMI is crap esp for stocky types with strong legs ,Michael Jones in his playing days and pro even McGod would be told to lose weight if you listened to BMI, so don't!
    proof:[url]http://nhlbisupport.com/bmi/bmi-m.htm[/url] (metric or imperial)
    try inputtng some AB players. I think Richie is 187cm and around 106-110kg now?
    Dan Carter is 28.7BMI-->fatso!



  • Yup, it's bollocks: body fat percentage is a more meaningful measure.  Needs some skill to get it right (calipers etc).  Athletes will have 6-13% body mass made up of fat, fit to fat bastard 'normal' people will range 14 - 25%, and over 25% is 'obese'.  15% is a good target.



  • Carl Hayman - 193cm, 120kg, BMI = 32.2 = OBESE!!!!!!!
    Phil Waugh - 175cm, 100kg, BMI = 32.7 = OBESE!!!!!!
    Tatafu Polota-Nau - 181cm, 113kg = 34.5 = OBESE!!!!!!

    And on it goes. Locks and backs are mostly 25-30, and front row and back row mostly 30+ except for the really tall guys.



  • I had a doctor pull the BMI shit on me once when I went to see him for a work medical certificate for having a flu.

    I would need to be under 110kg to not be obese, I haven’t been that weight since my uni days where it was normal to spend atleast 2 hours or so exercising each day.  Never gunna happen again I am afraid, unless cut off a leg or something.



  • I changed jobs a couple of yrs ago and realised I had no life insurance all of a sudden.  Insurance co. tried to load my insurance premium 100% because my BMI was 34 (well OK and the liver function and cholesterol results but still)



  • At 25.5, MvJ is on the cusp of normality  This must be incorrect...



  • Lack of muscle mass MvJ - most people store some weight as fluid too, whereas you're storing it as alcohol



  • [quote name='Nick the Aussie']
    [quote name='"Red Bull":3grdfv65']
    For some reason I thought you were taller than that Nick? Were you standing on a box in your wedding photos? 😁 You looked about 6'3 in those pics I reckon.[/quote]

    Yeah thanks Mrs the Aussie isn't the tallest girl in the world  but I likes em small I does :twisted:

    The electric pulses for body fat are no real indicator. They can be wildly inaccurate depending on how much you sweat, how hyrdated you are, and whether you're standing on the precise points for them. Body pinch is the only way.
    [/quote:3grdfv65]

    What about that thing they do on biggest loser, when you get in a huge tub and float while you're hooked up to some wires. Someone explain that in lamens terms for me???



  • :-k No fucking idea mate. Something about the density of fat and muscle - muscle is about three times heavier for the same volume.



  • Nicko after a bit of research its called - Hydrostatic Weighing to Measure Body Fat

    [quote]Hydrostatic weighing (underwater weighing) is the [b]most accurate way to calculate body fat [/b] - that is, if you can find a hydrostatic weighing tank.

    How does hydrostatic weighing calculate body fat? By using Archimedes Principle. Your examiner first calculates your body density by measuring the amount of water you displace when you immerse yourself in water. Then a formula is used to calculate body fat based on your body density. The problem is finding a facility (University, major gym or fitness center) which has a hydrostatic weighing tank[/quote]


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