Sports and Health
CHAPTER 8
SPORTS AND HEALTH
Sport is a preserver of health.
—Hippocrates (460?–377? BC)
The truth of Hippocrates's assertion has been nearly universally accepted for centuries, but only since the twentieth century have researchers worked to quantify the impact of physical activity, or the lack thereof, on physical and mental well-being. In Focus Area 22: Physical Activity and Fitness Progress Review (April 14, 2004, http://www.cdc.gov/nchs/ppt/hpdata2010/focusareas/fa22_progress_review.ppt), the Centers for Disease Control and Prevention (CDC) reports that about 1.2 million, or 48%, of the nation's 2.4 milliondeathsin2000werepreventable; and of those preventable deaths, 400,000, or 17%, were due to poor diet and physical activity.
Hippocrates may not have appreciated as fully the other side of the sports-health nexus. As sports become a bigger business and as the pressure to perform becomes increasingly intense, greater attention is being given to the potential negative health impact of sports participation, especially on children and youth.
BENEFITS OF PHYSICAL ACTIVITY
The CDC's Focus Area 22 is a progress report on one area of a broader initiative called Healthy People 2010 (http://www.healthypeople.gov/). It lists several benefits of physical activity and fitness:
- Builds and maintains healthy bones and muscles, controls weight, builds lean muscle, reduces fat and blood pressure, and improves blood glucose control.
- Decreases the risk of obesity and chronic diseases (coronary heart disease, high blood pressure, diabetes, colon cancer, and osteoporosis).
- Reduces feelings of depression and anxiety and promotes psychological well-being.
- Relates to functional independence of older adults and quality of life of people of all ages.
The specific health benefits of sports participation depend on the sport. Speed walking, jogging, cycling, swimming, and skiing have been shown to build cardiovascular endurance. Sports that involve gentle bending or stretching, including bowling, golf, and tai chi, are identified as promoting flexibility, which in turn may reduce the risk of injury. Other sports, such as those involving weightlifting or throwing, build strength. One important result of building strong muscles and, especially, bones is that it helps stave off osteoporosis by increasing the mineral content of bones. In "Lifestyle Factors and the Development of Bone Mass and Bone Strength in Young Women" (Journal of Pediatrics, June 2004), Tom Lloyd et al. of Pennsylvania State University report that exercise is more important than taking calcium supplements in promoting strong bones and that exercise was responsible for between 16% and 22% of the variation in hip bone mineral density in the eighty women they studied over ten years.
Coronary heart disease, diabetes, colon cancer, and high blood pressure can all be prevented or improved through regular physical activity. The CDC, in Physical Activity and Good Nutrition: Essential Elements to Prevent Chronic Diseases and Obesity, 2007 (April 2007, http://www.cdc.gov/nccdphp/publications/aag/pdf/dnpa.pdf), points to an obesity epidemic as the key factor in these chronic health problems. According to the CDC, the prevalence of obesity among adults between twenty and seventy-four years of age increased from 15% in 1976–80 to 32.9% in 2003–04. The obesity rate among teenagers more than tripled during this span, increasing from 5% to 17.4% for those in the twelve to nineteen age group. Youfa Wang and May A. Beydoun of the Johns Hopkins Bloomberg School of Public Health, in "The Obesity Epidemic in the United States—Gender, Age, Socioeconomic, Racial/Ethnic, and Geographic Characteristics: A Systematic Review and Meta-regression Analysis" (Epidemiologic Reviews, vol. 29, August 2007), project that by 2015, 41% of American adults will be obese.
aA moderate amount of physical activity is roughly equivalent to physical activity that uses approximately 150 calories of energy per day, or 1,000 calories per week. | |
bSome activities can be performed at various intensities; the suggested durations correspond to expected intensity of effort. | |
Washing and waxing a car for 45–60 minutes | Less vigorous, more timeb |
Washing windows or floors for 45–60 minutes | |
Playing volleyball for 45 minutes | |
Playing touch football for 30–45 minutes | |
Gardening for 30–45 minutes | |
Wheeling self in wheelchair for 30–40 minutes | |
Walking 1¾ miles in 35 minutes (20 min/mile) | |
Basketball (shooting baskets) for 30 minutes | |
Bicycling 5 miles in 30 minutes | |
Dancing fast (social) for 30 minutes | |
Pushing a stroller 1 mile in 30 minutes | |
Raking leaves for 30 minutes | |
Walking 2 miles in 30 minutes (15 min/mile) | |
Water aerobics for 30 minutes | |
Swimming laps for 20 minutes | |
Wheelchair basketball for 20 minutes | |
Basketball (playing a game) for 15–20 minutes | |
Bicycling 4 miles in 15 minutes | |
Jumping rope for 15 minutes | |
Running 1½ miles in 15 minutes (10 min/mile) | More vigorous less time |
Shoveling snow for 15 minutes | |
Stairwalking for 15 minutes |
Sports participation helps control weight by burning calories that would otherwise be stored as fat. The more vigorous the sport and the more frequent the participation, the more calories are burned. The article "How Many Calories Have You Burned?" (USA Today, February 26, 2007) reports on the number of calories that are burned in one hour of physical activity for those weighing 120, 154, and 170 pounds. For someone weighing 154 pounds, cross-country skiing for one hour would burn 559 calories; tennis, 489 calories; playing basketball, 440 calories; and bowling, 210 calories. Table 8.1 shows the time required to burn 150 calories doing a variety of sports and other physical activities. For example, playing a game of basketball for fifteen to twenty minutes burns 150 calories, the same number as playing volleyball for forty-five minutes, playing touch football for thirty to forty-five minutes, or swimming laps for twenty minutes.
Sports Participation and Mental Health
Besides the obvious physical benefits of sports participation, there appear to be psychological benefits as well. The press release "Univ. of Fla. Study: Sports Participation Has Mental Perks for All" (March 7, 2001, http://news.ufl.edu/2001/03/07/body-image/) reports that a 2001 survey conducted by University of Florida researchers found that athletes have a better image of their own body than nonathletes. The effect is visible without regard to sport, gender, or level of expertise. According to the press release, Heather Hausenblas, the study's lead author, posits that the effect is part of a broader improvement in self-esteem that accompanies sports participation. Based on Hausenblas's review of more than eighty other studies, athletes are 20% more likely than nonathletes to have a positive self-image. Competitive athletes have a better body image than casual athletes, and casual athletes have a better body image than nonathletes. The press release also quotes John Russell, the president of the American Fitness Association, as saying that even small doses of exercise can benefit people beyond the well-documented cardiovascular effects. Exercise, he said, can alter one's mood by releasing the brain chemical called endorphins. He speculates that endorphins, by putting the exerciser in a better mood, may indirectly improve an athlete's body image.
The idea that sports participation can help improve one's mood is well supported by other scientific research. For example, Rosemarie Kobau et al. report in "Sad, Blue, or Depressed Days: Health Behaviors and Health-Related Quality of Life, Behavioral Risk Factor Surveillance System, 1995–2000" (Health and Quality of Life Outcomes, July 30, 2004) that individuals who do not exercise tend to experience more days in which they feel sad. Another study, "Adolescent Women's Sports Involvement and Sexual Behavior/Health: A Process-Level Investigation" (Journal of Youth and Adolescence, 2004) by Stephanie Jacobs Lehman and Susan Silverberg Koerner, finds evidence of a link between girls' involvement in organized sports and positive sexual health and behavior. This study links participation in organized sports with positive behavior related to sexual risk-taking, sexual/reproductive health, and sexual/reproductive health-seeking behavior. This effect is connected to self-empowerment and a positive view of one's own body.
Youth Sports Participation as an Indicator of Adult Behavior
Participating in sports as a child or adolescent also increases the likelihood that a person will participate as an adult. In "Childhood and Adolescent Sports Participation as Predictors of Participation in Sports and Physical Fitness Activities during Young Adulthood" (Youth and Society, vol. 35, no. 4, 2004), Daniel F. Perkins et al. analyze data from the Michigan Study of Adolescent Life Transitions longitudinal study to examine the connection between sports participation in childhood and physical fitness into young adulthood. The researchers examine survey responses about sports participation from more than six hundred respondents when they were twelve, seventeen, and twenty-five years old and find that childhood sports participation is an excellent predictor of both fitness and participation years later.
Even though many of the previously cited studies highlight the value of sports participation for young people, the benefits of sports are truly multigenerational. According to the Gerontological Society of America, physical activity yields a number of benefits for the elderly as well as for the young. Exercise has been shown to be the key to maintaining mobility in older adults. This activity could be as simple as walking regularly.
HEALTH RISKS OF SPORTS PARTICIPATION
Injuries
TYPES OF INJURIES.
In Sports Injuries (April 2004, http://www.niams.nih.gov/Health_Info/Sports_Injuries/sports_Injuries_hoh.pdf), Mary Anne Dunkin of the National Institute of Arthritis and Musculoskeletal and Skin Diseases details the kinds of injuries athletes are likely to sustain and the activities in which they sustain them. Dunkin lists muscle sprains and strains, ligament and tendon tears, dislocated joints, and bone fractures as the most common types of sports injuries (See Table 8.2.) According to Dunkin, the knee is the most commonly injured joint, largely because of its complexity and its role in bearing weight. Every year, knee problems send over 5.5 million people to orthopedic surgeons. Knee injuries can result from twisting the knee awkwardly, a direct blow, landing badly after a jump, or overuse. Injuries can range in severity from a minor bruise to serious damage to one or more of the four ligaments—the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral—that stabilize the joint.
The Achilles tendon, which connects the calf muscle to the back of the heel, is another common site of sports injuries. Achilles tendon injures are especially common in people who do not exercise regularly and may not bother to stretch adequately before a game or session. This makes middle-aged "weekend warriors" particularly susceptible, according to Dunkin.
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A fracture is a break in a bone. It can come from a single event, in which case it is called an acute fracture; or it can be caused by repetitive impact, which is called a stress fracture. Stress fractures usually occur in the feet or legs, the result of the pounding these bones take from long periods of running and jumping. When the bones that come together to form a joint get separated, it is called a dislocation. Dunkin notes that the joints of the hand are the most common points of dislocation, followed by the shoulder.
Dunkin divides all sports injuries into two broad categories: acute and chronic. Acute injuries are those that occur suddenly during an activity. They are characterized by severe pain, swelling, and inability to use the injured body part. Chronic injuries usually occur through overuse over a long period. They usually result in pain when engaging in the activity, and a dull ache when at rest. There may also be swelling.
According to Maureen Haggerty, Teresa G. Odle, and Rebecca J. Frey in "Sports Injuries" (Jacqueline L. Longe, ed., Gale Encyclopedia of Medicine, 2006), the vast majority (95%) of sports injuries are minor soft-tissue traumas. These include bruises (or contusions), which occur when blood collects at the point of the injury, causing a discoloration of the skin. Sprains, which account for about one-third of sports injuries, are partial or complete tears of a ligament. Strains are similar to sprains. The difference is that in a strain the torn tissue is a muscle or tendon rather than a ligament. Other soft-tissue sports injuries include tendonitis (inflammation of a tendon) and bursitis (inflammation of the fluid-filled sacs that allow tendons to glide over bones). These two injuries usually result from repeated stress on the tissue involved rather than from a single event. The kinds of sports injuries that result from overuse appear to be on the rise among young people. Mark Hyman notes in "Young Athletes, Big League Pain" (Business Week, June 7, 2004) that in 1989 overuse injuries accounted for 20% of patients visiting the sports medicine clinic of Children's Hospital Boston. By 2004 the percentage was 70% and on the rise. Hyman blames increased pressure to perform from parents and coaches, who seek to turn every promising young athlete into a scholarship recipient and, eventually, a superstar.
Skeletal injuries from sports are less common than soft-tissue injuries. Haggerty, Odle, and Frey indicate that fractures account for 5% to 6% of sports injuries, with arms and legs being the most common sites of a break. Fractures of the skull or spine are rare in sports. Repeated foot pounding associated with such sports as long-distance running, basketball, and volleyball, and the stress fractures that can result, sometimes cause an injury called shin splints. Shin splints, according to Haggerty, Odle, and Frey, "are characterized by soreness and slight swelling of the front, inside, and back of the lower leg,
Recreational activity | Number of injuries |
Basketball | 512,213 |
Bicycles | 485,669 |
Football | 418,260 |
Soccer | 174,686 |
Baseball | 155,898 |
Skateboards | 112,544 |
Trampolines | 108,029 |
Softball | 106,884 |
Swimming/diving | 82,354 |
Horseback | 73,576 |
Weightlifting | 65,716 |
Volleyball | 52,091 |
Golf | 47,360 |
Roller-skating | 35,003 |
Wrestling | 33,734 |
Gymnastics | 27,821 |
In-line skating | 26,935 |
Tennis | 19,487 |
Track & field | 17,306 |
and by sharp pain that develops while exercising and gradually intensifies."
The most dangerous class of sports injuries are those to the brain. A violent jarring of the brain from a blow to the head is called a concussion. Concussions often cause loss of consciousness and may also affect balance, coordination, hearing, memory, and vision.
STATISTICS ON FREQUENCY AND INJURY RATES.
The article "Basketball Tops List of Sports with Most Injuries" (2006, http://www.luhs.org/feature.cfm?featureid=509) analyzes the prevalence of sports injuries using data from the U.S. Consumer Product Safety Commission. It indicates that of all sports injuries that were treated in hospital emergency rooms in 2005, basketball was the leading culprit, causing 512,213 of those injuries. (See Table 8.3.) Bicycling (485,669) and football (418,260) were close behind with injuries that required emergency room treatment. Soccer and baseball, the next two sports on the list, were far behind, causing 174,686 and 155,898 injuries, respectively.
Because they are still growing, and because their motor and cognitive skills are still developing, children and adolescents are particularly vulnerable to sports injuries. In "Facts about Childhood Sports Injuries" (2004, http://www.usa.safekids.org/content_documents/Sports_facts.pdf), Safe Kids Worldwide, a nonprofit network of organizations devoted to reducing accidental injuries of all kinds among children, reports that 3.5 million American children under the age of fourteen receive medical treatment for sports injuries every year. Sports participation in 2003 accounted for 55% of all nonfatal injuries at school and 21% of all traumatic brain injuries among children. In 2003, 205,400 kids between the ages of five and fourteen were treated in emergency rooms for basketball-related injuries. Football was close behind with 185,700 injuries. Even though baseball was the cause of fewer injuries treated in emergency rooms (108,300), it had the highest fatality rate among all sports, causing three to four childhood deaths each year.
FACTORS AFFECTING INJURY RATES.
Besides children and adolescents, Dunkin notes that middle-aged people and women of all ages are also particularly vulnerable to sports injuries. Middle-aged people are susceptible to injury because they are not as agile and resilient as when they were younger. Some people expect their bodies to perform as well at the age of fifty as they remember their bodies performing at age twenty or thirty. As a result, they put themselves at risk of injury. The risk is highest when an individual tries to make too quick a transition from an inactive lifestyle to an active one. As women's sports become faster paced and more physical, injuries among female athletes are increasing. The American Sports Data press release "New National Study Is First since 1970's to Document Full Range of Sports Injuries" (May 15, 2003, http://www.americansportsdata.com/pr-sportsinjuries.asp) notes that in 2002 women were the recipients of 40% of all sports injuries and 37% of emergency room admissions.
PSYCHOLOGICAL IMPACT OF YOUTH SPORTS PARTICIPATION.
Frank Brady states in "Children's Organized Sports: A Developmental Perspective" (Journal of Physical Education, Recreation, and Dance, February 2004) that the "positive effect of sports participation for some youths appears to be offset by the negative experiences of others." He quotes Arthur J. Pearl and Bernard R. Cahill in Intensive Participation in Children's Sports (1993), who state that "sports are like a double-edged sword. Swung in the right direction, the sword can have tremendously positive effects, but swung in the wrong direction it can be devastating. Adults who supervise children's sports hold the sword. Whether sport is constructive or destructive in the psychological development of young children greatly depends on the values, education and skills of those adults."
The biggest culprit in the negative psychological impact of youth sports participation is an overemphasis on competition, which Brady attributes to misplaced priorities on the part of the adults in supervisory roles.
As a result, there is a high rate of burnout and subsequent dropout in youth sports. Brady explains that sports participation peaks at age eleven and steadily declines through the teenage years. He singles out a subset of the dropout group under the category of "burnout." Burnout refers to young athletes who have been successful in their sport(s) and have participated intensively over a number of years; concentrated training at the expense of other activities can result in diminished enjoyment, competitive anxiety, and ultimately real psychological and emotional damage.
Brady also points to conflicts between heavy sports participation and cognitive development in young children. Most children are not capable of fully grasping the competitive process until about age twelve and have trouble understanding the complex interrelationships that form a team. Some adult coaches get angry and frustrated when, for example, young soccer players swarm to the ball rather than play their positions properly, when in fact many players at age seven or eight are physically incapable of absorbing the concept of a position.
The American Psychological Association (APA) argues that whether youths benefit from sports participation may depend to a large degree on their environment. The APA news release "Environment May Play a Role in Whether Youth Benefit from Sports Participation, According to Two Studies" (August 25, 2001, http://www.apa.org/releases/sportinvolvement.html) describes two studies with seemingly contradictory messages. A Clark University study of seventh graders from inner-city neighborhoods in central Massachusetts finds that boys and girls who participated in organized sports had higher self-esteem and were perceived by their teachers as having better social skills. Boys involved in sports were less likely to have experimented with marijuana. These positive traits were not accompanied by measurable negative behavior, such as increased aggression. However, the Clark University researchers explicitly caution against making "sweeping pronouncements about benefits or risks of sports involvement."
A larger study of female African-American students in rural high schools tells a different story. This study by Matthew J. Taylor of the University of Wisconsin, LaCrosse, finds that sports participation may actually increase the likelihood of substance use and other undesirable behaviors. Participation in sports did not appear to have a deterrent effect on gang involvement or other forms of delinquency. Taylor explains that the reason for conflicting results is that there are so many other variables involved, such as peer groups and community attitudes toward sports.
PHYSICAL INJURIES AMONG YOUNG ATHLETES.
Even though much of the attention to the hazards of youth sports focuses on the mental and emotional pitfalls, physical injuries are a major concern as well. As noted earlier, children as a group are particularly vulnerable to sports injuries. Bill Hewitt, in "Wearing out Their Bodies?" (People Weekly, June 13, 2005), elaborates on the theme of youth sports and their connection to increased injury risks. He cites many examples of young athletes pushed into extremely vigorous regimens at early ages and who end up damaging their bodies. One sports surgeon is quoted as saying that ten years ago, he had never seen a baseball pitcher under nineteen years old who needed the elbow ligament replacement operation known as "Tommy John surgery," whereas in 2004 he performed fifty-one such operations on teenage pitchers. Jeré Longman notes in "Fit Young Pitchers See Elbow Repair as Cure-All" (New York Times, July20, 2007) that some young athletes are now opting to have this surgery even in the absence of an injury, in hopes that it will enhance their capabilities. Hewitt takes parents to task for pressuring their children into trying to become the next Michael Jordan (1963–), when the odds of even the most talented young athlete ever making the big leagues, much less excelling there, are microscopic. He notes that about nine million boys play in organized baseball leagues, but that there are only about 9,700 players on Division I college teams, 7,500 minor leaguers, and 829 players in Major League Baseball. Hewitt advises parents and coaches that children need at least three months off each year from sports that involve throwing. He also urges them not to ignore discomfort, because pain is an indication of an injury that must be addressed.
According to the National Alliance for Youth Sports (NAYS), parents and coaches can play a big role in helping kids avoid injuries. NAYS points to three overarching strategies for minimizing the risk of sports injuries: wearing appropriate, sport-specific, properly fitting protective gear, including helmets and goggles; protecting the skin from damaging solar rays by wearing hats and sunglasses and applying sun block when playing sports in the sun; and keeping adequately hydrated by consuming sports drinks to replace lost fluids and electrolytes lost through sweat.
SPORTS AND HEALTH: THE OUTLOOK
Are Americans heeding all the advice coming from their doctors and their government about the importance of physical activity? Data from the Early Release of Selected Estimates Based on Data from the 2006 National Health Interview Survey (June 25, 2007, http://www.cdc.gov/nchs/data/nhis/earlyrelease/200706_07.pdf) by the U.S. Department of Health and Human Services indicate that, in general, the answer seems to be "not really." Figure 8.1 shows that the percentage of adults who engaged in regular leisure-time physical activity between 1997 and 2006 hovered at around 31%, in spite of the aggressive promotion of exercise by the federal government and others. As shown in Figure 8.2, people tend to exercise less as they age, and this pattern holds true for both genders, with men more likely to be physically active than women in every age category. White adults, at 34%, were more likely to engage in regular leisure-time physical activity than either Hispanics (23%) or non-Hispanic African-Americans (25%). (See Figure 8.3.)
Another survey, Physical Activity Survey, 2006 (April 2006, http://assets.aarp.org/rgcenter/health/fitness_06.pdf), by Teresa A. Keenan, finds that in 2006, 49% of adults had been physically active for at least a year and that 36% of adults preferred walking. (See Figure 8.4 and Figure 8.5.)
By contrast, vigorous physical activity among adolescents seems to be on the rise. The nonprofit research agency Child Trends reports in Vigorous Physical Activity by Youth (June 2006, http://www.childtrendsdatabank.org/pdf/16_PDF.pdf) that 68.7% of students in grades nine through twelve engaged in vigorous physical activity in 2005, up from 62.6% in 2003. (See Figure 8.6.) Child Trends finds that this increase was evident among both males and females, and among white, African-American, and Hispanic subgroups. "Vigorous physical activity" is defined as physical activity for at least twenty minutes that made the person sweat and breathe hard, such as basketball, soccer, running, swimming laps, fast bicycling, fast dancing, or similar aerobic activities, on at least three of the seven days preceding the interview. As shown in Figure 8.7, 78% of ninth-grade boys in 2005 reported doing vigorous physical activity, whereas 68% of ninth-grade girls reported such activity. Even though the percentages for both genders declined from ninth to twelfth grade, boys were consistently more active than girls, with the gap between the genders the widest in twelfth grade. White and Hispanic students were about equally likely to have engaged in vigorous physical activity, at 70% and 69%, respectively; African-American students, at 62%, were somewhat less likely to be physically active. (See Figure 8.8.)
In the face of an obesity epidemic in the United States, the federal government has in recent years taken an active role in promoting fitness among Americans. In 1996 the National Center for Chronic Disease Prevention and Health Promotion published Physical Activity and Health: A Report of the Surgeon General (http://www.cdc.gov/nccdphp/sgr/pdf/sgrfull.pdf), a blueprint for improving the physical condition of the U.S. population. Among the report's major conclusions were that people of all ages and genders benefit from regular physical activity and that significant health benefits can be obtained by engaging in a moderate amount of physical activity, such as forty-five minutes of volleyball, thirty minutes of brisk walking, or fifteen minutes of running. The report noted that additional benefits can be gained through more vigorous and greater amounts of activity. Since then, the federal government has continued its efforts to promote physical fitness through a variety of programs, including Healthy People 2010 and the HealthierUS initiative (http://www.healthierus.gov/), promoted by President George W. Bush (1946–).
In recent years network television has taken on the obesity epidemic as well. The National Broadcasting Corporation's The Biggest Loser is a reality show in which eighteen obese contestants compete in various contests designed to help them slim down. The contestant who sheds the most weight (the "biggest loser") is the winner at the end of the season. The American Broadcasting Company counters with Shaq's Big Challenge, in which the National Basketball Association star Shaquille O'Neal (1972–) encourages a group of overweight youths to adopt a healthier lifestyle, including a better diet and more physical activity.