With society's ever increasing price tag of education, public schools have gone to great lengths to cut costs from the unessential activities during and after school hours. First it was the obvious luxury of music programs and art classes; however, with the desperate need for teachers, athletic programs have felt the grunt of this expedition. Now, more than ever, youths in our communities are battling serious problems. Not only are sports and organized athletic programs vital to physical development, but also mental growth and offer children structure and goals. Unfortunately, many schools have to cut back or even eliminate sports / athletic programs due to lack of funding. As the cost of athletic programs increase, many states are forced to pass the fees along directly to students.

According to national statistics, there is a 25% to 30% reduction in participation when fees are implemented. Consequently, many of the students who benefit most from athletic programs cannot afford to participate. School funding cannot be solely to blame for the decrease in physical activity in the education environment. With the increased emphasis on the need to achieve academic aptitude, children as well as their adult parents see athletics as an extra, or something that can be done when and if homework is completed.

Not to say that this is not commendable, but evidence supports the fact that athletic programs have the ability to turn at-risk youth in positive directions. Sports programs promote healthy social and physical development while offering positive alternatives to high risk behavior. Reduced physical activity represents one of the most significant changes in lifestyle that has been observed during the twentieth century. Our sedentary lifestyle and the reduced energy requirements of the majority of our jobs has been a source of comfort in a business world where efficiency and productivity are sought. The impact of the transition from a traditional to a modern lifestyle on daily energy needs can be estimated by various means.

By using the doubly labeled water technique and indirect calorimetry, Singh et al. (1) showed that the energy cost of living at the peak labor season was as high as 2. 35 resting metabolic rate (RMR) in Gambian women. When this value is compared to results usually obtained in women living in industrialized countries, 1. 4 to 1.

8 RMR (2, 3), it can be estimated that for a given body weight, a modern lifestyle may have reduced the energy cost of living by as much as 1 to 4 MJ/day. Accordingly, a recent analysis by Prentice and Jebb (4) has emphasized the contribution of sedentariness to the increased prevalence of overweight in the United Kingdom. Despite these observations, the contribution of exercise to the prevention and treatment of obesity is still perceived as trivial by many health professionals. The perception of many of them was recently well summarized by G arrow (5) who stated that exercise is a remarkably ineffective means of achieving weight loss in obese people, mainly because their exercise tolerance is so low that the level of physical activity that they can sustain makes a negligible contribution to total energy expenditure. When one looks at the currently available literature, it is difficult to disagree with this statement.

Indeed, numerous studies have demonstrated that when exercise is used alone to treat obesity, body weight loss is generally small (6). In addition, the further weight loss generated by adding an exercise program to a reduced-calorie diet is also often small if not insignificant (7). Traditionally, the study of the impact of exercise on body weight control has focused on its energy cost and on the hope that the body energy loss will be equivalent to the cumulative energy cost of exercise sessions. In practical terms, this means for instance that if a physical activity program induces an excess of energy expenditure of 2000 kcal / week , a similar energy deficit should be expected in the active obese individual. Recent experimental data show that such a view is not realistic since it does not take into account the compensations in other components of energy balance which may either attenuate or amplify the impact of exercise on body energy stores. It thus appears preferable to consider exercise as a stimulus affecting regulatory processes, which can ultimately affect all the components of energy balance instead of only focusing on its energy cost.

The objective of this chapter is to summarize recent developments in knowledge pertaining to the effects of exercise on energy balance. Clinical implications of these notions are also addressed. With the passing decades, a person's work role is a major social identity for most adults, with almost all men and the majority of women participating in the labor force in most contemporary postindustrial societies. No longer is work and home lives considered separate entities, today, they are one in the same. Many aspects of employment are relevant to body weight and obesity (1). Employment provides financial resources through income, and also access and opportunities for using health care services.

Many jobs include health benefits and risks, some related to body weight such as involvement in healthy levels of physical activity or the stress of working varying schedules in 'shift work' (2). An important aspect of employment is that working usually imposes an organized structure on people's lives and provides a social world that is different from the family and household social network. Despite the potential relevance of work to patterns of body weight, relatively little explicit attention has focused on patterns of work and weight. However, employment information is reported in studies of other aspects of weight. Some studies in postindustrial societies find that women who are not employed are more likely to be obese than their counterparts who participate in the labor force (3).

Unemployed men have been reported to be underweight (4). Fuller analysis of employment and employment transitions such as entering the workforce, changing jobs, and retiring need to be conducted to understand their role in body weight and obesity. Overall, even though the majority of adults in developed societies are employed outside the home, there is a dearth of information about how employment influences obesity. Mechanisms for activity level and caloric intake from employment are not well worked out, so employment and obesity deserves additional research attention in the future. Occupation Occupation is the type of work that a person performs in a society. The occupations are diverse, and can be classified on many dimensions relevant to body weight.

While occupation has not been a focus in most of the weight literature, differences in weight levels and the prevalence of obesity do occur. Women in low prestige jobs tend to be more obese, but the relationship between occupation and weight is less consistent for men (5). Energy intake is not necessarily determined by occupation, although jobs that are related to food preparation (such as cooks, clerks in businesses that sell food, etc. ) may provide eating opportunities that facilitate overeating. Some occupations also have obligations for employees to eat to perform their jobs, such as salespeople who are expected to take clients to meals, etc. Another aspect of some occupations related to energy intake is whether they are structured to permit, enhance, or prevent eating on the job.

Some jobs are flexible about eating at work, while others rigidly provide set times where eating can occur. Many work sites offer food service to their employees, which provides a source of calories that may either facilitate or prevent obesity, depending on how the food service is used. Energy expenditure varies considerably by occupation. Some jobs involving high levels of energy expenditure over extended durations of time, while others involve minimal physical activity for long periods. On this basis, some workers expend many calories over the course of their workday and may be underweight, while others spend long sedentary hours at work that can contribute to obesity. Occupations also vary in the flexibility they offer to workers to engage in recreational exercise.

Some jobs encourage workers to exercise before, during, and after their workday, and even provide work site recreational facilities and organized exercise programs. By contrast, other jobs offer no opportunities or facilitation of exercise for their employees. Another occupational consideration is selection of people into particular jobs because of their weight. Occupational prestige tends to be inversely associated with relative body weight, especially for women, with higher status occupations having thinner workers (10). There is considerable documentation of weight discrimination during the hiring process against the entry of obese individuals ino many jobs, particularly those with higher prestige and public visibility (6-8).

Additionally, upward occupational mobility is limited or restricted for obese individuals due to weight discrimination in the promotion process (9-11). This suggests that body weight influences occupation, in addition to occupation influencing body weight, and that the disentanglement of those two causal processes is difficult. Overall, the high proportion of both men and women who participate in the labor force in postindustrial societies and the long hours that are spent at the work site suggest that occupation has the potential to become an important factor in the prevalence and treatment of obesity. Occupations provide lifestyles that play a role in eating, exercise, and weight management. Weight and work are topics that need to be examined more completely in the future. Income Income is the wages and other benefits provided through employment, as well as from other sources such as investments, inheritance, and government assistance programs.

Income provides resources that can influence energy intake and expenditure, which in turn shape body weight. One of the most consistent patterns in the obesity literature is the direct association between income and body weight in men and women in developing nations, and the inverse association between income and weight among women (and perhaps men) in developed societies (10). There is some debate about whether the direction of causality operates as income influencing weight, weight-influencing income, or both (1). Income provides opportunities to exercise control over many aspects of life, including diet and activity levels, and can be used to seek the thin ideal that exists in most postindustrial societies.

Low-income levels produce stress, which may lead some people to store more body fat as insurance against difficult times in the future, and others to seek solace from their troubles through the comfort of eating. Energy intake appears to have an inverted 'U's hoped relationship with income, with the lowest and highest income groups ingesting fewer kilocalories of food than middle income individuals (0). Income facilitates control over energy intake by providing resources that permit a person to select foods. Resources are an important consideration in making food choices (12, 13). Having adequate income allows someone to focus on other aspects foods than cost, such as health and caloric value. People who experience hunger or food insecurity may overeat when food is available, which leads lower income groups in some societies to be more likely to be obese (4).

In postindustrial societies, people with higher incomes have the resources to purchase more expensive low-fat or dieting products to attempt to control their weight, as well as to enroll in sometimes costly weight control classes and programs. Energy expenditure is generally inversely associated with income at work because most higher paying professions require less caloric activity on the job than the manual, physical labor of many low paying jobs. However, those with higher incomes are more likely to have the resources to afford living in low crime neighborhoods where they can safely participate in outdoor recreational activities. Higher income individuals also can afford to pay for recreational exercise equipment, classes, coaching, travel, etc. Overall, income is a powerful predictor of body weight levels and obesity. In postindustrial societies, higher income women in particular are thinner and less likely to be obese.

Income provides many resources that permit people to avoid or overcome obesity, and needs to be considered in examining patterns of obesity and interventions to prevent or reduce obesity. Education Education is usually seen as the amount of formal schooling that a person has experienced. Education provides knowledge about eating, nutrition, activity, health, and weight that is used in assessing food and activity choices and in managing body weight. Education also socializes people into the dominant norms of society about fatness and thinness, providing them with motivations as well as skills to conform to cultural weight expectations. In developing societies men and women with the most education tend to be heavier than their peers, although often not fat by the standards of developed societies (10). In postindustrial societies and groups, people with the highest levels of education are least likely to be obese (6).

The relationship between education and body weight appears to be bidirectional in postindustrial societies (1). People with lower education have less knowledge about nutrition, activity, and weight, and are more likely to become obese. Additionally, obese people are more likely to be discriminated against in acquiring greater education because they are excluded from admission to various educational opportunities (6). Energy intake is not clearly associated with education in postindustrial societies (1).

People with the lowest levels of education are more likely to eat higher fat foods and less likely to consume fruits and vegetables, but also may experience lower food intake. Energy expenditure is inversely associated with education (1). People who have the least education tend to have jobs that involve more manual labor and those with the most education have more mental and interaction al labor included in their daily work. Energy use in recreational activities is more frequent among those with higher education, who are more likely to participate in sports and exercise programs specifically to manage body weight. Overall, education is one of the strongest predictors of body weight and obesity in populations, with more highly educated people being thinner. The knowledge, thinking skills, and normative socialization acquired through education appear to be important in preventing gaining of body weight during adulthood, and dealing with weight gains that do occur.

Public investments in education for the population may be one of the most effective ways to limit the development and lower the prevalence of obesity. Household Size Household size is the number of people that a person resides with in their household or home. Household size is related to eating patterns, activity levels, and body weight, particularly among some portions of the population such as the elderly. In particular, living alone is a risk factor for problematic eating, activity levels, and body weight. Little research attention has been given to household size, weight, and obesity among the general population. Among the elderly, however, living alone can be a risk for under nutrition and insufficient body weight even though the collective findings of studies of eating alone and weight are mixed (5).

Energy intake does not necessarily vary by household size (1). However, energy intake is influenced by the presence of others. Commensality is important in encouraging adequate food intake (6), and people who eat alone frequently do not eat enough to maintain body weight levels (7). A body of work on social facilitation concludes that there is a direct relationship between the number of people who are present at meals and the amount that people consume (8).

This suggests that household size may influence energy intake, with the more people who live in a dwelling unit the more calories they each consume. Energy expenditure may be influenced by household size in various ways. Interacting with other individuals involves additional activity beyond being alone. Such interaction may lead to expending more energy among people in larger households. Especially if there are children in a household, people spend more time moving around than when others are not present.

Overall, the number of people with whom a person lives has the potential to influence their caloric intake, activity level, and values about body weight. A particular concern exists for people living alone. However, these relationships between household size and weight have not been a focus of past research and deserve more attention in the future. 1. Sobal J. Obesity and socioeconomic status: A framework for examining relationships between physical and social variables.

Med Anthropol 1991; 13 (3): 231-247. 2. Amelsvoort LG PM, Sc houten EG, Kok FJ. Duration of shift work related to body mass index and waist to hip ratio. Int J Obese 1999; 23: 973-978.

3. Sobal J, Rauschenbach B, Frongillo E. Marital status, fatness, and obesity. Soc Sci Med 1992; 35 (7): 915-923. 4. Montgomery SM, Cook DG, Bartley MJ, Wadsworth MEN.

Unemployment, cigarette smoking, alcohol consumption, and body weight in young British men. Eur J Public Health 1998; 8 (1): 21-27. 5. Pagan JA, Davila A.

Obesity, occupational attainment, and earnings. Soc Sci Quart 1997; 78: 756-770. 6. Larkin JC, Pines HA. No fat persons need apply: Experimental studies of the overweight stereotype and hiring preference.