Reduced physical activity and its association with obesity

Sociodemographic diversity and behavioral medicine

The broad array of economic and cultural diversity in the U.S. population correlates with and impacts on the study of behavioral aspects of health. The purpose of this article was to provide a selective overview of behavioral medicine research on sociodemographically diverse populations, with a focus on ethnicity, gender, and socioeconomic status. Suggestions are provided with regard to methodological refinement of research and insights into possible future directions in behavioral medicine research on ethnically and economically diverse populations.

Lipid, protein and carbohydrate intake in relation to body mass index

OBJECTIVE

To examine whether the same amount of energy intake has different consequences on body mass index (BMI), depending on the source of energy from specific macronutrients.

DESIGN

Cross-sectional study, in the context of the European Prospective Investigation into Cancer and nutrition (EPIC).

SETTING

Communities all over Greece.

SUBJECTS

A total of 27 862 apparently healthy volunteers, men and women, ages 25-82 y.

INTERVENTIONS

None.

METHODS

Dietary information was collected through an interviewer-administered semi-quantitative food frequency questionnaire. In the context of a cross-sectional analysis, we calculated changes of BMI per increments of energy intake from protein, carbohydrates, saturated, polyunsaturated and monounsaturated lipids and ethanol, controlling for mutual confounding and other confounders, among all participants, and after exclusion of under-reporters and/or those on a diet.

RESULTS

Protein intake was positively associated with BMI. The association was evident when nutrients were not mutually adjusted for and increased after mutual adjustment among nutrients (beta=0.80 kg/m(2) per 418.4 kJ or 100 kcal increment, 95% confidence interval 0.55-1.06 for men, and beta=1.59, 95% CI 1.30-1.88 for women), as well as after exclusion of under-reporters and/or those on a diet. The effects of other macronutrients were less substantial or consistent.

CONCLUSIONS

There is evidence indicating that protein intake is conducive to obesity. Moreover, our data suggest that neither saturated or monounsaturated lipids nor carbohydrates are likely to play a major role in increasing BMI over and beyond that indicated by their energy content.

Perceived disability and observed functional limitations in obese women

OBJECTIVE

To describe perceived disability in obese women.

DESIGN

Comparisons of perceived disability in obese women and in a normal-weight reference group regarding activities of daily life (ADL), mobility, housework and professional work as well as comparisons of perceived disability and observed functional limitations reported in a previous study.

SUBJECTS

Fifty-seven consecutively selected obese female outpatients, mean age 44 y (body mass index (BMI) 37 kg/m2) and 22 voluntary referents, mean age 49 y (BMI 22 kg/m2).

MAIN OUTCOME MEASURES

A pain questionnaire (for background data) and a disability questionnaire, which is new, detailed and specific with test-retest stability and content- and criterion-referenced validity. Comparisons of results from the questionnaire and a functional test regarding observations of similar functional limitations.

RESULTS

The obese women perceived disability to a much higher extent (P<0.003) than did the normal-weight women. The main problems concerned occupational work in strenuous positions, strain and pain, sports, walking outdoors or on stairs, and moderate housework requiring squatting, stooping or lifting. Rising from sofas, pedicure and stress incontinence were problematic. The correlation between perceived disability and functional limitations was fairly good (r(s)=0.56) but ranged widely (r(s)=0.14-0.61). Within the group of obese women the disability neither correlated to BMI nor age, rather to lower-body pain.

CONCLUSION

The disability questionnaire conveyed new and detailed information of disability problems in everyday life in obese women. It highlighted the difference between the disability these women may perceive and the functional limitations we can observe and measure. This result is of great clinical relevance in the care of obese women.

Effects of two frequencies of walking on cardiovascular risk factor reduction in Mexican American women

The beneficial effects of moderate-intensity exercise on cardiorespiratory fitness and body composition are well documented, with the greatest health benefits reported in sedentary individuals who engage in moderate levels of exercise. The published literature contains no quantification of the threshold of lower limits of beneficial exercise or estimates of benefits derived from lower exercise levels. The specific aim of this study was to compare the effects of two walking frequencies, holding intensity and duration constant, on blood lipids, body composition, and exercise maintenance regimens of Mexican American women. A quasi-experimental design, with two treatment groups and one comparison group, was used to explore the dose-response effects of low-intensity exercise on cardiovascular outcomes. Significant interactions were found between walking and total serum cholesterol and skin-fold sums. This study demonstrated the clinical efficacy of a low-intensity exercise regimen on cardiovascular risk factors and exercise adherence.

Functional limitations linked to high body mass index, age and current pain in obese women

OBJECTIVE

To describe functional limitations in obese women.

DESIGN

Comparisons of functional limitations in obese women and in a normal-weight reference group regarding mobility, balance and housework transport.

SETTING

A large room with a corridor and staircase nearby.

SUBJECTS

Fifty-seven consecutively selected obese female outpatients, mean age 44 y, body mass index (BMI) 37 kg.m(-2), and 22 voluntary references, mean age 49 y, BMI 22 kg.m(-2).

MAIN OUTCOME MEASURES

Pain questionnaire (for background data); a new valid and reliable test protocol measuring activities of daily life (ADL), pain and exertion, heart rate, balance and speed.

RESULTS

The patients had problems in performing 13 of 16 actions compared with the references (P-values between 0.05 and 0.001). They moved more slowly and had difficulties and /or pain and exertion in flexibility tasks, balancing, activities at floor level (bending and kneeling), climbing stairs and carrying groceries. BMI (P=0.002), age (P=0.02) and current pain (P=0.02) from the lower body predicted functional limitation.

CONCLUSIONS

The functional test reflected functional limitations in obese women, revealing difficulties and perceived pain in ADL. The test protocol can be used to evaluate the effects of training or dieting. For clinical use we recommend considering BMI, age and current pain for use when individualizing advice on training.

Body mass index in relation to energy intake and expenditure among adults in Greece

The empirical evidence concerning the quantitative relations between energy intake and expenditure on the one hand and body mass index (BMI) on the other is inconclusive. We have used a large database of 14,281 individuals, for whom habitual dietary intake and expenditure have been ascertained with adequate methodology, to examine the mutually adjusted associations of these variables with BMI. Study subjects were adult participants in the Greek component of the European Prospective Investigation into Cancer and Nutrition (EPIC) study. After adjustment for age and gender and exclusion of dieting individuals and energy underreporters, an increment of about 500 kcal intake was found to correspond to an increment of about 0.33 kg/m2 of BMI, whereas an increment of about 5 MET-hours of energy expenditure was associated with a decrease of about 0.18 kg/m2 of BMI, where MET is the ratio of the metabolic rate associated with a given activity to the resting metabolic rate. Our results indicate that increasing physical activity is about half as effective as decreasing energy intake in reducing BMI.

Patterns of body weight in the Baltic Republics

OBJECTIVE

Previously recorded rates of obesity in the Baltic Republics have been among the highest in the world although little is known about how they vary within the population. This study investigates the distribution of body mass index (BMI) and obesity in these countries.

DESIGN

Three cross-sectional surveys conducted in the summer of 1997.

SETTING

Estonia, Latvia and Lithuania.

SUBJECTS

Representative national samples of adults with measured weight and height (Estonia: n=1154; Latvia: n=2292; Lithuania: n=2096).

RESULTS

Between-country differences are particularly large among women: women from Latvia and Lithuania are approximately three times as likely to be obese as those from Estonia (17.4%, 18.3%, 6.0% respectively); only about one-third of this difference is explained by the sociodemographic and behavioural factors studied. In men, the prevalence of obesity varied only slightly among countries (Estonia: 9.9%; Latvia: 9.5%; Lithuania: 11.4%). While the prevalence of obesity increases with age within each republic, particularly in women, it is not associated with nationality or urban/rural region, and no consistent association is observed with income. Obesity is inversely related to education in Latvia and in Lithuanian women. Latvian men and women and Lithuanian men who smoked had a lower prevalence of obesity than non-smokers. Leisure time physical activity was not associated with obesity.

CONCLUSIONS

Obesity is a major health problem in the Baltic Republics, particularly among Latvian and Lithuanian women. The lack of association between obesity and most demographic, socioeconomic and behavioural factors suggests that the problem is generalized. Health promotion strategies aiming at preventing and controlling excess weight gain in the Baltic Republics will need to target the general population.