Written by Dan Gwartney, MD
09 April 2007

     "Arnie's obese" scream the headlines, referring to bodybuilding legend Arnold Schwarzenegger. Want proof? Just look at the numbers. The government says it's true; his BMI is so high, even Richard Simmons would consider him a lost cause. Is this a case of "numbers don't lie" or is the Austrian Oak a victim of statistics?

    Inacuracy Guaranteed
When dealing with large groups, statistics are used to describe risks and behaviors. While these numbers are useful in describing the general nature of a group, they provide little value in dealing with individuals; inaccuracy is nearly guaranteed when attempting to define any one member by studying the group. This fact is realized by nearly every individual who is exposed to the fallacy of applying statistics into actual practice.

A perfect case in point is the way athletes, particularly bodybuilders, are categorized by the BMI. The BMI (Body Mass Index) is a number based upon a calculation that defines a person as underweight, normal, overweight or obese. This determination is made using only the gross measurements of height and weight, without regard to body composition. The high chance of error in judging bodybuilders using the BMI should be obvious.1

The majority of Americans do not exercise rigorously, and only a very small percentage lift weights using routines that would induce muscle growth. Because of this general trend, the BMI assumes most people have a limited amount of muscle.2-5 While this may be true for desk jockeys, couch potatoes and fast food junkies, it nullifies any value of the BMI for muscular athletes.6,7 In fact, many of the popular media outlets have enjoyed being able to jokingly label Arnold and Sylvester Stallone as obese, and call Mel Gibson, Brad Pitt and Michael Jordan overweight.6 The news reports used these ludicrous examples to point out the fallacy in applying the estimates of common people to exceptional individuals.

In fairness, the government realizes the BMI is imperfect and adds certain caveats to its interpretation.8 The guideline recommends considering medical history and waistline in evaluating a person for obesity. Unfortunately, people like having a simple number to label others, and the BMI is black and white when it comes to calling someone healthy or obese. If someone is 5-foot-8 and weighs 200 pounds, he is obese. Whether he is the current light-heavy titleholder from the NPC nationals or the body double for Homer Simpson, it makes no difference. The BMI is absolutely worthless as a measure of fitness or "fatness" when dealing with athletes, especially bodybuilders. Providing a national "weight" standard without considering muscularity suggests the guideline authors might have been locked in a room without ESPN. Perhaps they think "resistance training" is part of an anger management course or some type of civil disobedience?

Muscularity vs. Obesity
This position is clarified in an excellent text, Physiology of Sport and Exercise.9 Following a clarification of body size versus body composition, the authors delve into the more specific and accurate measures of "fatness," methods which directly measure the amount of body fat and lean body mass.

Most bodybuilders are familiar with skin fold calipers and underwater weighing, two techniques used to determine the percentage of body weight that is fat. These methods would allow a coach, physician or dietician to rapidly decide whether one is overweight due to an excess of fat, or has greater muscular development than the average person. By determining the body fat percentage, an accurate assessment of one's fitness, or fatness, can be readily obtained. Why doesn't the government use body fat levels? Primarily because of the extra work and expense necessary to measure body fat in large numbers of people.
 
    The "Shape" We're in
Since the advent of more readily available human growth hormone (GH), the competition shape of bodybuilders has changed. With few exceptions, the waists of bodybuilders have gone from tapered to blocky and distended. Even at the amateur level, it is not unusual to see several competitors with "GH" belly. Growth hormone, in addition to its anabolic and fat-burning properties, causes the organs in the abdomen to grow, bloating and stretching the trunk.1012 Further, prolonged use and excessive doses can lead to growth of the bones of the face and hands, resulting in a disturbingly freakish appearance.13 Despite allowing for larger and more massive bodybuilders, many feel the introduction of GH has had a negative impact on the sport and has spoiled the symmetry and athleticism that defined bodybuilding in the 1970s and ‘80's.

America is suffering from an epidemic of obesity and weight-related health crises; this is unquestionable.8,14,15 However, the measures used to define obesity have often tagged athletes, bodybuilders in particular, as part of that epidemic. True bodybuilders are conditioned muscular athletes. Due to the greater muscle mass attained as a result of a disciplined diet, rigorous training and the use of anabolic drugs or supplements, bodybuilders commonly weigh more than is considered "desirable" by the government and insurance analysts who apply the criteria used to judge normal, sedentary people.

It's impossible to say whether maintaining a greater muscle mass than average increases or reduces health risks at this time. What is certain, is that it is unfair and improper to use the guidelines developed for the general public as the rule for the bodybuilder, who is the exception. Until sufficient research has been done to look at the impact of muscularity on health, there is no justification for labeling any conditioned athlete as overweight or at increased risk for serious health problems. However, it should be clear that any implied health benefit of conditioning may be offset by the health risks associated with the use of certain drugs or extreme diets.

"Arnold Schwarzenegger is obese." It's a conclusion only a governmental panel of experts could arrive at.

References 
1.    Anonymous, National Institutes of Health. Classification of overweight and obesity by BMI, waist circumference, and associated disease risks. Available through http://www.nhbli.nih.gov/health/public/heart/obesity/lose_wt/bmi_dis.htm accessed August 5, 2002.
2.    Widemark S. The fallacy of BMI measurements. Available through http://www.suewidemark.netfirms.com/bmi.htm accessed August 5, 2002.
3.    Himes JH, Bouchard C. Do the new Metropolitan Life Insurance weight-height tables correctly assess body frame and body fat relationships? Am J Public Health 1985 Sep;75(9):1076-9.
4.    Wakat D. Obesity vs. overweight: know the difference. Scimedica Available through http://www.scimedica.com/resource/articles/article.asp?ID=40 accessed August 5, 2002.
5.    Pai MP, Paloucek FP. The origin of the "ideal" body weight equations. Ann Pharmacother 2000 Sep;34(9):1066-9.
6.    Smith S. Who you calling fat? Boston Globe 2002 Jul 30;Health and Science section.
7.    Anonymous, National Institutes of Health. Understanding adult obesity. Available through http://www.niddk.nih.gov/health/nutrit/pubs/unders.htm accessed August 5, 2002.
8.    Anonymous, National Institutes of Health. Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults. NIH publication No. 98-4083. Available through http://www.nhbli.nih.gov/guidelines/obesity/ob_gdlns.htm accessed August 6, 2002.
9.    Wilmore JH, Costill DL. Physiology of sport and exercise, second edition. Human Kinetics, Champaign, IL, 1999;pp 492-503.
10.    Macintyre JG. Growth hormone and athletes. Sports Med 1987 Mar-Apr;4(2):129-42.
11.    Smith DA, Perry PJ. The efficacy of ergogenic agents in athletic competition. Part II: Other performance-enhancing agents. Ann Pharmacother 1992 May;26(5):653-9.
12.    Dawson RT. Hormones and Sport: Drugs in sport - the role of the physician. J Endocrinol 2001;170:55-61.
13.    Anonymous. We started noticing that his toes and fingers, as well as his ears, began growing and so was his head. Available through http://www.anabolicsteroids.com/acromegaly.html accessed August 7, 2002.
14.    Kenchaiah S, Evans JC, et al. Obesity and the risk of heart failure. N Engl J Med 2002 Aug 1;347(5):305-313.
15.    Sternberg S. Study: Putting on extra pounds increases heart failure risk. USA Today 2002 Aug 1;9D.