Enduring Questions: What's Your Ideal Weight?

Dropping five pounds will make you healthier and help you run faster - as long as you have them to lose, that is

Posted: 8 November 2007
by Amby Burfoot

Some runners don't worry much about their weight. They think: I run, therefore I can eat a cow for dinner. But these same runners gain 3.3 pounds per decade, according to a recent US analysis of 4,700 mid-life male runners by the National Runners' Health Study. That's not a lot, but it adds up, and the gain affects even those running more than 40 miles a week. The same runners also gained three-quarters of an inch around the waist every decade. I've always monitored my body weight and there are two real reasons to get on the scales every Saturday: I want to find and maintain my healthiest weight, and I also want to determine my fastest weight.

Twenty years ago I read some early studies on body mass index (BMI) and longevity and cringed. People of my BMI – I'm relatively tall and skinny, with a BMI of around 21.0 – were dying at a younger age than others who were a little heavier than me. On a recent visit to California, I visited Dr Bill Haskell, to ask him about the weight and longevity question. He's the director of Stanford University's Prevention Research Center and a man who's been at the epicentre of important health-fitness debates for 30 years. "Those first studies failed to eliminate some people who were thin because they smoked cigarettes or were already diseased," Haskell told me. "The newer studies show no increase in mortality until BMI falls into the mid-eighteens," he said.

The Department of Health recognises the Body Mass Index. The underweight/unhealthy BMI cutoff is 18.5, which indicates malnourishment. If your BMI is 18.5 to 24.9, you're in the normal/healthy weight range. From 25.0 to 29.9, you're overweight, and health risks (such as diabetes, high blood pressure, and heart disease) start climbing. Anyone above a 30.0 BMI gets labelled obese and faces dramatically higher health risks. A 2001 Department of Health study found that 47 per cent of men in England and 33 per cent of women are overweight and an additional 21 per cent of men and 23 per cent of women are obese. Being overweight and obesity increase with age. Visit www.nhlbisupport.com/bmi/bmicalc.htm to find your BMI.

Fat and fit?

While it seems certain that higher body weights are unhealthy, fitness counts, too. Steven Blair, who describes himself as "short, fat, and bald," is one of the top experts in the BMI, exercise, and health field. He and his former colleagues at the Cooper Aerobics Center in Dallas, Texas, have collected the world's most impeccable fitness data; they've actually tested thousands of subjects on a treadmill. Most large studies are based on questionnaires that ask: "How much do you exercise during a typical week?" And you just know a lot of people are wildly optimistic (or lying) when they answer that question.

The Cooper Center studies show that aerobic fitness is a predictor of longevity. Indeed it's often better to be fat but fit rather than lean and out-of-shape. Fitness can trump fatness. Blair, a lifelong runner, believes we focus too much on weight, demonising and demoralising fat people. "I'd like to banish the whole idea of ideal weight," he says. "We simply don't have enough data to say what's right for any individual or group. We should focus more on telling people they can get healthier by becoming more active, no matter what their weight." That's a great message, and one we should all take to our non-exercising, overweight friends. They need every bit of motivation they can get. Still, we should also remember that weight loss is almost always good. Because lean and fit will always trump fat and fit.

Fast losers

Of course, some runners are more interested in fastness than fitness. They want to know: what's my best weight for fast 5Ks and marathons? Will losing weight help? The answer is almost always yes. But, as with BMI, only to a point. Lose too much weight and you become weaker and slower, not stronger and faster. Many parents worry about anorexia nervosa. A recent US study showed that anorexia affects about 0.6 percent of the overall American population, but four to six times as many young athletes. Since some anorexics actually starve themselves to death, concern is justified.

Still, there's no denying that healthy runners will race about two seconds per mile faster for every pound they lose. Weight loss boosts maximal aerobic capacity (VO2 max), essential to distance-running potential, because the less weight you carry around, the more miles per gallon you get from your oxygen. And losing a few pounds makes running easier, so you should be able to increase your workout distance and speed. Losing weight helps you to train harder.

Recently the University of Dayton, Ohio runner and physiologist Paul Vanderburgh has focused more academic attention on the subject. A couple of years ago, Vanderburgh, who ran a 3:31 marathon at 77.1kg, decided to devise a calculator that would ‘equalise' performances among runners of different weights. When he had finished his research, Vanderburgh validated his calculator at several Ohio road races, where it performed well. He published his study in the Journal of Exercise Physiology and put his calculator, which he calls the Flyer Handicap Calculator, on the Internet. You can get there from www.snipurl.com/agesexweightcalc. And the calculator can be used to compare, say, a 25-year-old woman who weighs 54kg with her 55-year-old, 75kg father. "I hope the Flyer Handicap Calculator will level the playing field a little, and give more motivation to heavier runners," Vanderburgh says. For those who simply want to lose weight to get faster, he has this advice: "lose fat, not muscle". Fortunately for runners, many studies have shown that exercise-based weight-loss programs help you achieve this goal much better than diet-only plans. "If you're not already doing some strength training, you might want to begin, because it's a great way to retain muscle and burn calories," says Vanderburgh.

I've never had much luck with strength training, but maybe it's time to try. I've lost five pounds this year, on top of 10 in previous years, by eating less pasta and rice and more fruit, vegetables, and fibre, and drinking water instead of fruit juice. I'm still heavier than my college weight, but I've narrowed the gap to 3-4kg. The result: my BMI is still above 18.5, my race times are dropping, and best of all, I feel great.

Lose Weight, Gain Speed

This table, based on changes in maximal aerobic capacity, provides a rough estimate of how much your race times will improve if you lose weight, as long as you have it to lose. If your BMI drops below 18.5, you're at risk of becoming weaker and slower.
12.4 secs
25 secs
52 secs
31 secs

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Discuss this article

THe new home-page thingy all about weight loss and what not....

Well ive never actually calculated my BMI...but at present, I am RIGHT at the upper-limit of the 'normal' category (77kg & 179cm). Even when I put in 75kg...whcih I am some days, im still at the upper end of the scale.

Now I dont think I am overly porky, but I do like my cake. Im also not ridiculously heavily built, most people say I am fairly skinny (but are they just being polite?)

I know body fat % is probably a better indication, but I dont have a huge amount of that either I dont think....im sure I had it measured once and it was 12%...I think.

Am I just made up of particularly dense matter? (I know that statement is leaving em wide open to certain comments!)

.......Or am I simply a fat bloater in denial?!

Posted: 08/11/2007 at 14:55

I'm fat


I'm proud!

Nick - you're skinny

Posted: 08/11/2007 at 14:57

The one that i sawe dind't include the body type either - so doesn't take into account the body frame
Posted: 08/11/2007 at 15:03

...oh stump you're just SAYING that..... *blushes coyly*

Seriously though...I dont have a massive frame, I not carrying excessive blubber (i dont think)....yet I am within a fairy cake of being 'fat' - 24.3

How does that work...or how is that justified?

Posted: 08/11/2007 at 15:21

acording to BMI (whichisa pile of rosh) i was over weight when i did IMDE ...and i was in singl figure body fat then

Posted: 08/11/2007 at 15:22

21.8 normal, but Mrs NGL says I am too skinny.  I am.

I don't know the answer Nick, but if thats a recent picture, then the BMI stuff is just wrong, unless you are a very strange shape?

Posted: 08/11/2007 at 15:24



Think about what its asking you for:

Height and weight.

Then think about how that weight can be made up... you could be all fat or all muscle, or somewhere in between. Clearly tendancy toward muscle is healthier than tendacny towrds fat, yet the BMI calculator doesn't make any allowances for this, so a 12st fat monster will have the same bmi as a 12st toned afleet of the same height.

Posted: 08/11/2007 at 15:27

.....yeah my arse is HUGE!


Posted: 08/11/2007 at 15:33

You barsteward I thought you havd burned that one
Posted: 08/11/2007 at 15:34

Then I would respectfully suggest you entered incorrect details when you said this:

Well ive never actually calculated my BMI...but at present, I am RIGHT at the upper-limit of the 'normal' category (77kg & 179cm). Even when I put in 75kg...whcih I am some days, im still at the upper end of the scale.

Unless you were talking about yo ass. Or talking out of it.

Posted: 08/11/2007 at 15:36

ha ha ha ha ha!
Posted: 08/11/2007 at 15:43


Quote from the BMI site linked to from the home page...

  • It may overestimate body fat in athletes and others who have a muscular build.
  • It may underestimate body fat in older persons and others who have lost muscle mass.
  • So, as chocolate teapots go...

    Posted: 08/11/2007 at 15:52

    DoT....i see your point....and it makes sense. THing is I dont think I am either of those.

    ANyhoo...I dont think the RW article stressed enough of the limitations of the measure of BMI, which could lead some people to worry overly. I know the context of the BMI....but it shouldnt be a universally accepted measure, which it generally is IMO.

    Im not bothered with my weight...id like to lose about 1/2 stone, (so I could hopefulyl be faster!) but I cant see it happening (cos I cant be arsed). I was however a little surprised just how close to being considered 'overwieght' I am based on this measurement.

    Posted: 08/11/2007 at 16:03

    ...posted previous comment before reading the one above it by DoT!

    'nuff said

    Posted: 08/11/2007 at 16:11



    the other thing to consider is that if you run (which you do) and you consider yourself to be carrying too much excess fat (which apparently you do - I can't comment), then you will have the double wammy (weight wise) of muscle plus fat combining to give you a higher BMI.

    If you continue to train for endurance events then your body fat percentage will probably come down (calories in permitting), eyt your muscle mass will probably also continue to grow slightly, so the reductiion in your bmi may not be proportional to the amount of body fat you lose.

    As a tool for the sedate masses bmi is a useful indicator and no more, as an indicator of fitness for purpose in anybody who does regular exercise and wishes to improve competietively its about as useful mas the aforementioned chocolate teapot. IMO

    At the rsik of starting a heated debate, I regularly use a set of Tanita scales to monitor bmy body fat and water content. These also make assumptions about body make up, but are more sophisticated than the bmi tables and allow you to define by sex and exercise habits. Since I train 10hrs a week or more in one way or another I qualify for the "athlete" setting - which gives me a good feeling in itself!!

    Posted: 08/11/2007 at 16:15

    I am almost obese - I am very overweight but according to BMI will still be slightly overweight at MY ideal which is where I look and feel my best - so I ignore BMI - load of carp designed to panic people
    Posted: 08/11/2007 at 16:20

    I is an aferleet too DoT! I got a card in the post which says so from UK Athletics or something like that!

    We can compare how lardy we are DoT at La Rochelle over a nice cake and coffee in a Patiserie! (well I can whinge and whine!) while you gloat over your new PB!

    Maddy...I agree...load of carp!

    Posted: 08/11/2007 at 16:32

    BMI is a load of poop.   A lot of muscle hides the lack of fat. Making you appear more 'normal' than you are!
    Posted: 08/11/2007 at 16:56

    My experience of BMI is that it is generally a better indicator with ladies than with men, but can be questionable for either. Nick - if your body fat is 12% then if anything it's on the low side. This suggests that a lot of what you think is excess weight is actually muscle, which weighs more than the same volume of fat. You also have to take into account body types - ectomorph is the lanky one, endomorph is the curvy one and mesomorph is the muscley one. Ectomorphs tend to look OK (i.e. not gaunt or ill) at the lower end of the 'healthy' BMI range. Endomorphs and mesomorphs tend to look better a little heavier. You are stuck with your basic type whatever you do diet and exercise wise. 

    There's something in the Competitive Runner's Handbook about weight and it reckons I should aim for something which I'm sure I'd feel and look pretty rough at to get my optimum time (I did weigh that much briefly once after a rather nasty tummy bug), and that's as someone who tends to stabilise at the lower end of the 'healthy' BMI range. And then we wonder why eating disorders are so prevalent among athletes...

    I think looking in the mirror and how you feel more generally healthwise are much better indicators than scales.

    Posted: 08/11/2007 at 17:55

    I like the bit about 'stop the press taking minutes off your time could be as simple as losing a few pounds'

    That's hilarious - Personally losing a few pounds is a lot HARDER than putting in 10 hours of training every week.  The training I do already - the losing the few pounds I have struggled with for years to no avail. 

    Posted: 08/11/2007 at 18:37

    BMI is tosh. I am officially overweight with a BMI of 25.8, I just need to be 4 inches taller that's all! I have no hang ups about my weight at all and I will continue drinking diet stella because I like it.
    Posted: 08/11/2007 at 18:51

    I think I have a similar BMI to Nick which just shows how rubbish it is. Nick is a mean lean running machine and I am a mother of 3 with inherent padded areas
    Posted: 08/11/2007 at 22:15


    Its just gonna fuel the already weight obsessed peeps on here

    and reinforce the fact that bigger is abd, and makes you a crap runner

    its ok to run slowly

    its ok to be a bit bigger-if you are healthy

    which i am-rudely so

    that having been said-my pbs this year are probably cos of a bit of weight loss

    it wasnt training

    Posted: 08/11/2007 at 22:18

    Nick, from what I recall you're a very elegant package of solid muscle

    I didn't read the original because I tend to skip past Amby Burfoot's articles (I get the impression that the old geezer has lost his marbles and needs putting out to pasture) and I've already considered and discarded the idea of trying to lose weight in the hope of getting some PBs by the back door. As GA says, it's easier to train harder than it is to lose even a few pounds off a frame that's already fairly lean.

    Posted: 08/11/2007 at 22:29

    I love this debate and would like to highlight a few points:

    The entire crew of the Olympic Coxless fours were obese by BMI standards at the last Olympics.  Additionally all the endurance athletes where in the stavation zone.  Does this means they are about to have coronaries/keel over? Well, no it means they're the correct body shapes and trained long and hard to be specific for thier events.  Which to a lesser extent we all are and as such BMI becomes less relevenant as you move away form the mainstream and towards the odd, i.e. runners. 

    With that said I have got faster as I have lost weight and race better at 66kg than 69kg.  When I was a junior I was a lot faster and raced at 62.5kg which I would love to get back to.

    Additionally people now call me skinny but when I was a junoir I about average, now that is scary.  The general population see me as skinny when my waist is now 3" larger!!!

    Posted: 09/11/2007 at 09:30

    Some interesting comments on this thread....both with regard to the validity of BMI, and how it could or perhaps should be applied to afferleets like us!

    Given that, and the various other comments on this thread, I question whether RW was/is right in publishing the article in its current format. (although I dont have the magazine...so perhaps there is more detail in there about the limitations??) Should there have been a greater emphasis on the limitations within the article itself...I assume the magazine doesnt have hyperlinks etc!!!

    As RW is (presumably) targeted at runners...although of ALL abilities, surely the fact that BMI has recognised limitations when it comes to 'athletic' people (such as runners!), which SOME people who read the mag and site will be more 'athletic' than others......by that I mean BMI is less applicable to them, than others. (Please recognise that I am trying my best here to not offend people......some people are 'better' runners than others, but the fact that you're out there having a go is what is important....your achievements are all very much relative!!)

    As people have already said....BMI is tosh/crap etc in some circumstances.

    Hope I dont inadvertantly offend peeps with my inane ramblings....I just think now that perhaps RW could have published this with a greater level of responsibility. At the end of the day though it is up to us to consider and interpret stuff.

    Oh and thanks Mrs P & V-rap....but i think you must confuse me with someone else!

    Posted: 09/11/2007 at 09:53

    Look guys, I've got the exact opposite problem. My BMI is 19 (170cm, 55kg), which is on the lower edge of normal. But I think it is really not a good indicator of how people look. I swear, I don't look really skinny at all, that is maybe because my fat is distributed not 100% proportionally. It's more on my thighs and bottom than on my upper body. As a consequence I am 1 dress size bigger below. I really train a lot and hard, but this difference from my upper to my lower body doesn't change. 

    Just to underline that I don't look really skinny: one of my runner colleagues once told me that I was "too fat" to run a 10k really fast. 

    So BMI or not, I don't think it is so easy to determine that one can run faster. I don't think it's much of an indicator really for running....

    Posted: 09/11/2007 at 10:38

    No Nick they haven't you have an excellent level of muscle tone and I suspect that is why your body fat is lower yet your BMI in the overweight range - and you are an very good example of why BMI is bollox
    Posted: 09/11/2007 at 10:39

    But these same runners gain 3.3 pounds per decade, according to a recent US analysis of 4,700 mid-life male runners by the National Runners' Health Study.

    So, this study, did it look at 4700 non-runners and compare how much weight they put on in 10 years? I know plently of me ho would be delighted if they only gained 3.3 pounds in 10 years! Isn't it normal for people to gain weight as they get older, because your metabolism slows down?

    He talks about the other guy who beleives that weight doesn't matter like he's clearly deluded!

    Posted: 09/11/2007 at 11:10

    Coming from the other end of the scale to some of those above, I don't trust BMI at all - at 184cm and 59kg my BMI is 17.4 so I'm technically unhealthy and underweight. Until around a month ago other pressures meant I was not doing any running at all, yet no weight gain. When I was training very hard to run a 40.33 10K last May my weight didn't change at all, nor when I last trained for a marathon. I've never been on a diet in my life, snack all day long on biscuits and fruit, and get regularly fed to bursting by the nice ladies at my church, but my weight doesn't change. I probably do increase the amount I eat when I run more, but my body seems to automatically stay in a happy equilibirum with me apparently underwieght. I don't believe that I'm unhealthy or that putting on an extra 3.5kg (if I was able to) to reach BMI 18.5, would improve my speed.

    Why do researchers keep banging on about BMI when it is so mis-leading? 

    Posted: 09/11/2007 at 11:36

         BMI is tosh/crap etc in some circumstances.

     I actually think it's the other way round. For the VAST majority of folks BMI is a reasonably guage or at least a good starting point but for some folks it isn't. The average punter isn't an olympic rower or an endurance runner. AND these days the average punter is FAT.  But because they are ALL fat they think that they are normal.

    I have had folks with a BMI in the 30's saying but surely BMI doesn't apply cos then rugby players would be in the 30's and anyway I'm not that fat and I go the gym now and again!!!!!!!!!!!!!!!

    Posted: 09/11/2007 at 12:43


    it is funny you should mention that your weight doesn't change although when training. Mine doesn't either. I can train as hard as I like (5 - 6 times a week with 2 big speed seshs and 1 long run) and nothing changes. This has already prompted me to wonder if I did anything wrong... 

    Maybe our non-weight change means simply that we have reached the lowest healthy weight that there is for our constitution.  

    Posted: 09/11/2007 at 12:54

    Agreed BMI calculation is flawed.  I'm 5ft 3 weigh 65 kilos and am just, only just, in normal weight band.  One pound more and I'd be obese on BMI calculations, but consistently run 3:35 marathons which I like to think an obese person couldn't / wouldn't?

    think my BMI comes out at 65 which really miff's me!

    Posted: 10/11/2007 at 21:30

    LOL 26 if it was 65 that would be interesting
    Posted: 10/11/2007 at 21:31

    65? You right porker!!
    Posted: 10/11/2007 at 21:34

    I'm a good stone heavier than I should be but, that said, in the last month I've pb'd at half and full mara - 7.5 year and 6.5 year pb's respectively.  Seemingly the extra weight isn't proving too detrimental to my long distance running!  Over 10k and below I suspect it is.
    Posted: 10/11/2007 at 21:43

    I regularly have big hefty blokes hammering past me in races of up to 10k.

    My BMI is just above 20 and I'm 18 pounds heavier than my theoretical "ideal running weight", which is a very scary 6st 6lb (and is what the likes of Gete Wami actually *do* weigh). And that ideal running weight may well be fine for an elite long-distance runner, who is likely to be genetically designed to function well at a lighter weight - elite athletes tend to be a self-selected group with attributes that give them advantages in their particular sport.

    But I'm not genetically the same as an elite long-distance runner and I'm not going to starve myself to try to get back to a weight I haven't been since I was 11 in order to be a little bit better at a sport I'm never going to be very good at. Or even to lose 5lb

    There's more to life. Including the joy of eating cake and not being hungry  

    Posted: 10/11/2007 at 22:19

    Was talking to an exercise physiologist (and holder of the Irish ironman record) about this today, as it happens.  He does fitness assessments for both athletes and people off the street every day.  He said that he doesn't put much emphasis on BMI at all.  Reckons it's a reasonable assessment of fatness and risk of disease in the average relatively inactive person....but not at all accurate for athletic people.  He believes in waist-hip ratio more for sedentary people and would rely on skinfold assessments for athletes.

    So boo to BMI.  Also had me all anxious before, despite fat measurements being fine....

    Posted: 10/11/2007 at 22:37

    I'm 5 ft 10 and weigh 12 stone, and so am a notch or 2 off of being overweight, yet I have no "spare".

    Years of fitness work of all types resulted in this 12 stone and now plenty of running doesn't shift any more.

    I reckon that your body find it's optimum weight for the demands that you put upon it.

    No doubt I could run faster if I lost 2 stone - but neither will happen.

    I do ok though and am wayyy bigger than most folks who beat me.
    Posted: 10/11/2007 at 23:15

    So, I have a BMI of 24 which is one point away from being overweight, and I hope to go sub3 first go at FLM.

    Who's mad, me or the Medics ?
    Posted: 10/11/2007 at 23:22

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