Jan 29, 2015Quiet Danger
As football players’ sizes have crept up in the past decade, so have the number of athletes diagnosed with metabolic syndrome–a precursor to health issues that can result in early death.
By Dr. Linda Lee & Dr. John Helzberg
Linda Lee, MD, is a Gastroenterology Fellow at the University of Missouri-Kansas City School of Medicine. John Helzberg, MD, is a Physician in the Division of Gastroenterology and Liver Disease Management Center at Saint Luke’s Hospital of Kansas City. He can be reached via post mail at: 4320 Wornall Rd., Suite 240 Kansas City, MO 64111.
The United States is facing an obesity epidemic–our children, adolescents, and teenagers are at risk. In fact, one in three teens is currently classified as obese or overweight. And unfortunately, athletes are not immune.
The problem is most prevalent in football, especially among linemen. In 2005, 552 NFL players weighed over 300 pounds, compared to only 39 in 1992. The average weight of an NFL player in 2006 was 248 pounds.
Once a rare sight in the NFL, extra large linemen are now not unusual–even in high school football. Younger athletes are impressionable, and if their favorite NFL player is overweight, they might think it’s appropriate that they are, too. Recent data suggests that linemen ages eight to 15 have a higher incidence of obesity and are generally overweight when compared to the other players on the team.
In many cases, already obese players are encouraged by their coaches to get even larger in order to become more competitive linemen. Unfortunately “bigger, faster, stronger” has been an accepted dogma in football for many years.
But there are dangers in “fattening up for football.” At the top of the list is metabolic syndrome, a precursor to many health problems, including diabetes, obstructive sleep apnea, non-alcoholic fatty liver disease, and stroke.
The good news is that athletes diagnosed with the condition can alter their nutrition and workouts to counteract its effects while still succeeding on the field. Athletic trainers and strength coaches can play an important role by being vigilant to the signs and symptoms of metabolic syndrome.
DEFINING THE DANGER
The American Society of Endocrinology and the World Health Organization state that metabolic syndrome is defined by the presence of at least three of the following five clinical parameters:
– Blood pressure ≥ 130/85 mm Hg – Fasting glucose ≥ 100 mg/dL – Triglycerides ≥ 150 mg/dL – Waist circumference ≥ 100 cm (40 inches) – High-density lipoprotein ≤ 40 mg/dL.
Metabolic syndrome has been studied extensively in adults and the findings can be applied to the adolescent population. The overall prevalence of metabolic syndrome in children and adolescents is approximately three to four percent. In adults 20 to 29 years old, prevalence doubles to approximately seven percent.
Multiple research studies have been conducted investigating the health of football players, including their rates of obesity, metabolic syndrome, and cardiovascular disease. The following studies demonstrate the prevalence of these health issues among football players.
NFL: A 2008 study from the National Institute for Occupational Safety and Health evaluated the health of 510 retired NFL players who played between 1972 and 1988. Although overall mortality was no higher in the retired football population than the general population, the investigators found that defensive and offensive linemen had a 52 percent greater risk of dying from heart disease than the general population.
In addition, 28 percent of obese players (classified in this study as having a BMI of at least 30 kg/m2) died before they reached the age of 50, while only 13 percent of non-obese players died before their 50th birthday. The cardiovascular mortality of linemen from congestive heart failure or heart attacks was three times that of non-linemen. And players in the largest BMI category showed a six-fold increase in their risk of heart disease. It was concluded that an increased risk of death was associated with a greater BMI.
Unfortunately, professional football players are becoming larger and heavier. In a review of 1,168 NFL players from the 2003-04 season, 56 percent had a BMI of at least 25 kg/m2 (the “classic” definition of being overweight), and 26 percent had a BMI of at least 30 kg/m2 (the “classic” definition of obesity). Overall, the players had similar cardiovascular disease profiles when compared to the general population, but a higher prevalence of prehypertension and hypertension.
Waist circumference and waist-to-height ratio may be more accurate parameters to assess obesity in muscular football players. However, even when researchers used these measurements in addition to BMI, the results were similar to the BMI-only studies.
For example, in a retrospective analysis of 69 NFL players, only linemen were found to have metabolic syndrome. They also had higher BMIs, waist circumferences, and waist-to-height ratios, and increased visceral obesity than non-linemen. Current data suggests that visceral obesity may predispose individuals to early onset coronary artery disease and carry an increased risk of malignancy.
College: A 2011 study of 39 college football players compared linemen to non-linemen and found that 14 percent of the linemen had metabolic syndrome while none of the non-linemen did. Another study of NCAA Division I football players from 2009 demonstrated a strong association between obesity, the presence of metabolic syndrome, and insulin resistance.
Twenty-one percent of the players on the team in the 2009 study were classified as obese and nine percent of them had metabolic syndrome. All of the linemen were obese and had metabolic syndrome. The odds ratio for the development of insulin resistance in players who were obese was 10.6 times greater than that in non-obese players.
High school: A 2007 study that analyzed over 3,000 Iowa high school linemen found that 45 percent of them were overweight. An additional nine percent of the linemen were classified as severely obese (BMI greater than 35 kg/m2). The average BMI increased by grade to a high of 28.5 kg/m2 for seniors.
Despite the fact that these athletes with metabolic syndrome engage in strenuous exercise, the health problems associated with unhealthy weight gain are not erased. We advise those professionals who work with athletes at risk for metabolic syndrome to encourage them to continue exercising, but also see a sports dietitian who can stress the importance of a low-fat, low-carbohydrate, weight reduction nutrition plan. This should be emphasized as a long-term change and not a temporary diet, because an athlete’s cardiovascular disease risk rises after their athletic career has concluded.
In addition, counseling should stress the importance of continued exercise and cardiovascular conditioning to mitigate these cardiometabolic risks. Some athletes may be “pushed” by their coaches and/or parents to gain weight with the intent of obtaining a collegiate scholarship. These adults also need to be advised of the potential significant health risks associated with marked weight gain in their child.
Multiple studies have looked at the various types of diets that may be beneficial in reducing risk factors associated with metabolic syndrome. A low glycemic index diet is preferred over a high glycemic index diet. Total fat reduction (25 percent of calories should come from fat) and a balanced calorie restriction (500 to 1,000 fewer calories per day) can be beneficial to maintain weight loss.
And 150 minutes of moderate physical activity per week is recommended. These guidelines are safe and recommended in the Physical Activity Guidelines for Americans from the U.S. Department of Health & Human Services.
The prevalence of metabolic syndrome among football players, particularly linemen, is a real danger. The larger the player, the higher his risk for development of metabolic syndrome, hypertension, diabetes, sleep apnea, non-alcoholic fatty liver disease, and heart disease. These risks increase when their football careers have concluded, particularly if they continue to consume a high calorie diet and don’t engage in enough physical activity.
“Fattening up for football” is usually not healthy, and changes in diet and exercise often must be made to reduce the risk of disease. Though following through on the changes is up to the athletes, athletic trainers and strength coaches have the ability to be of great assistance.
To view references for this article, go to: www.Training-Conditioning.com/references.