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—————- The next find out more meeting for our March programme is on Tuesday 23rd February which is in [cntdwn todate=”28 January 2020 23:59″ timeoff=”0″ showhours=”0″ showmins=”0″ pretext=””] Check myrise.co.uk/briefing-meeting to find out more, see what the meeting involves and, potentially, take that next step to transforming your life and body 🙂 ———————-
If you ask most FitPros what they think about Body Mass Index, they’ll tell you it’s “rubbish”.
Up until a few years ago, I’d have said the same.
They, and others, will point out it puts bodybuilders and rugby players down as obese.
I’ve heard that so many times, I’d accepted it as truth.
But, like many things we accept, there’s actually little evidence of it.
There’s a couple of key questions that should be asked of that statement:
1. What percentage of the population are bodybuilders and rugby players?
2. Out of those, what percentage have an obese BMI and a none obese body fat percentage?
I’ll be honest, I’ve struggled to find definitive answers to either of those questions.
I would image number one is under 10% though.
Probably under 5.
For number two I’ve found studies that say numbers around 15% of rugby players have an obese BMI (over 30).
And I can’t imagine that every single one of them has a none obese BF%.
As for bodybuilders?
Hard to be mega accurate.
But, a quick Google suggests the Rock has a BMI of just over 30.
How many people do you see on a daily basis that are built like The Rock?
None I’d guess.
They clearly exist.
But there’s not all that many of them.
So it’s probably safe to say the proportion of the population that are rugby players or bodybuilders and have a BMI in the obese category, and a BF% that’s none obese……….
Is less than 1%.
Of course, the better question would be “What percentage of the general population have an obese BMI and a none obese BF%?”
And whilst I can’t answer that for the world as a whole……….
I can answer that for every member we’ve ever had at RISE.
A quick export to excel of every assessment we’ve ever done………..
And a comparison of BMIs to BF%………..
Shows that the number of people for whom BMI and BF% don’t correlate (have a obese BMI and a none obese BF%) is………..
0.75%.
And those few had a BF% at the top end of ‘overweight’, but not obese.
And, further number crunching can show what total body weight every single person would be…………….
When they hit the NHS recommended body fat percentage levels (dependant on age, which I’ve accounted for, and given as a range which I’ve gone for the middle of)……………..
Assuming maintenance of all ‘non-fat’ weight.
And we can see what BMI those those people would then have at that weight (”underweight’ (under 18.5), ‘normal’ (18.5 to 25.0), ‘overweight’ (25.0 to 30.0) or ‘obese’ (30+)).
And the number of people who would still have an obese BMI at a non-obese body fat percentage was…………
2.5%.
If we drop the ‘target body fat’ percentage to the ‘ideal’ that number drops to……….
0.2%.
If we were to factor in that not all of the lean mass would be retained (drop in water retention mainly), then both numbers hit zero.
So, realistically, everyone who has ever had their assessment done at RISE would have an non-obese BMI if they had the body fat levels the NHS recommends.
And the size of the group often quoted as ‘disproving’ BMI is probably a fraction of 1%.
As always, your BMI and BF% (along with everything else) is entirely your choice.
No one should tell you what yours ‘should’ be.
Least of all us.
But……………
Just letting you know that………….
Despite what many will tell you……………..
BMI is actually a pretty reasonable measurement.
Much love,
Jon ‘BMF’ Hall and Matt ‘MFI’ Nicholson
