Biomedical subjects

R R Wing

Publications and source records attributed to R R Wing.

At least 37 records · Page 2Linked to original sources

PubMed2000

Weight gain during menopause. Is it inevitable or can it be prevented?

The years surrounding the menopause are associated with weight gain, increased central adiposity, and decreased physical activity. While weight change occurs independent of menopausal status, adverse changes in body fat distribution and body composition may be due to hormonal changes occurring during the menopausal transition. The one factor most consistently related to weight gain is physical activity. To avoid weight gain, women should make regular physical activity a priority. Although HRT use is widely believed to cause weight gain, data from the PEPI trial do not support this belief. Moreover, HRT may have a protective effect in reducing central adiposity, although more long-term studies using CT or MRI to measure visceral fat are needed to confirm this hypothesis. Data from the Women's Healthy Lifestyle Project provide clear evidence that weight gain and increased waist circumference, along with elevations in lipid levels and other CHD risk factors, are preventable through use of lifestyle intervention in healthy menopausal-aged women. Given the prevalence and chronic course of obesity, weight gain prevention should be recognized as an important health goal for women before they approach menopause.

Body Composition↗

PubMed2000

Long-term maintenance of weight loss: current status.

Intervention strategies for promoting long-term weight loss are examined empirically and conceptually. Weight control research over the last 20 years has dramatically improved short-term treatment efficacy but has been less successful in improving long-term success. Interventions in preadolescent children show greater long-term efficacy than in adults. Extending treatment length and putting more emphasis on energy expenditure have modestly improved long-term weight loss in adults. Fresh ideas are needed to push the field forward. Suggested research priorities are patient retention, natural history, assessment of intake and expenditure, obesity phenotypes, adolescence at a critical period, behavioral preference-reinforcement value, physical activity and social support, better linkage of new conceptual models to behavioral treatments, and the interface between pharmacological and behavioral methods.

Adolescent↗

PubMed2000

Cross-cutting themes in maintenance of behavior change.

This article reviews the cross-cutting themes and research recommendations that emerged from the National Heart, Lung, and Blood Institute "Maintenance of Behavior Change in Cardiorespiratory Risk Reduction" conference. Throughout the conference participants emphasized that maintenance should be conceptualized as a process rather than merely as the last step in the behavior change process. Researchers should focus on understanding how those who are successful at long-term maintenance complete this process and on developing new approaches that can be used to help those who are not successful. Further attention to the following topics was encouraged: observational studies of the natural history of successful long-term behavior change, development of new technologies for measuring health behaviors, better theoretical understanding of the differences between initial behavior change and maintenance, development of strategies to increase participation rates and long-term effectiveness of formal treatment programs, new approaches to increase the effectiveness of self-help interventions, and better understanding of the development of behavioral patterns in children and adolescents.

Adolescent↗

PubMed2000

Vegetarian and weight-loss diets among young adults.

OBJECTIVE: Young adults frequently experiment with vegetarian and weight-loss diets. Comparisons of their experiences on these two different diets may help in the development of approaches to improve long-term adherence to weight-loss regimens. In the current study vegetarian and weight-loss diets were compared on how long and how strictly they were followed, and reasons why they were initiated and discontinued. RESEARCH METHODS AND PROCEDURES: From 428 college students surveyed, four groups were delineated: 1) 59 participants had been following a vegetarian diet but not a weight-loss diet (Vegetarian), 2) 117 participants had tried a weight-loss diet but not a vegetarian diet (Weight Loss), 3) 133 participants had followed both a vegetarian and a weight-loss diet (Both), and 4) 119 participants had not tried either diet (Neither). RESULTS: Differences were examined by comparing the Vegetarian and Weight-Loss groups as well as by comparing the two diets within the Both group. Duration of the vegetarian diet was much greater than the weight-loss diet; most participants in the Vegetarian group (62%) remained on their diet for more than 1 year, whereas the majority of the Weight-Loss participants (61%) followed their diet for 1 to 3 months. Similar results were found when comparing the two diets within the Both group. How strictly the two diets were followed, however, did not differ. Analyses revealed that reasons for discontinuing a diet varied; participants were more likely to cite boredom as a reason for discontinuing a weight-loss diet than a vegetarian diet (53% vs. 5% between groups and 30% vs. 10% within the Both group). DISCUSSION: The longer duration of the vegetarian diet relative to the weight-loss diet warrants further investigation. Results could possibly be applied to behavioral weight-loss treatment to improve long-term maintenance.

Adolescent↗

PubMed2000

Does weight loss maintenance become easier over time?

OBJECTIVE: Studies of health-related behaviors, including weight loss, have shown that risk of relapse decreases over time, although reasons for this relationship are unclear. The purpose of this cross-sectional study was to determine if subjects who have maintained weight losses for varying periods of time report different strategies for weight loss maintenance or differences in the effort and pleasure associated with weight maintenance behaviors. RESEARCH METHODS AND PROCEDURES: Subjects were 758 women and 173 men who had maintained losses of at least 30 lb (mean = 60 lb) for 2 years or longer (mean = 6.8 +/- 7.0 years). Self-administered questionnaires assessed subjects' use of weight maintenance strategies in the past year and their perceptions of the effort, attention, and pleasure associated with weight maintenance. RESULTS: Subjects who had maintained weight losses longer used fewer weight maintenance strategies and reported that less effort was required to diet and maintain weight and that less attention was required to maintain weight. The pleasure derived from exercise, low-fat eating, and maintaining weight was unrelated to duration of weight loss maintenance. DISCUSSION: As duration increases, a shift in the balance between the effort and pleasure of weight maintenance may occur. This shift may increase the likelihood of continued maintenance.

Adult↗

PubMed2000

Primary prevention of weight gain for women aged 25-34: the acceptability of treatment formats.

OBJECTIVE: To determine if treatment format will affect the willingness of women aged 25-34 to participate in a program for primary prevention of weight gain. DESIGN: 102 normal-weight women aged 25-34 were randomized to one of three treatment formats (group meetings, correspondence course, no-treatment control). Acceptability was evaluated by determining the proportion of women participating in their assigned format. Efficacy was assessed by determining mean weight changes at post-treatment (10 weeks) and 6-month follow-up, and the proportions of women who remained at baseline weights. RESULTS: Significantly fewer women chose to participate in a group format, compared to the correspondence course and no-treatment control (42%, 84% and 62%, respectively). However, the group format produced the largest short-term changes in weight (-1.9+/-1.8 kg, -1.1+/-2.1 kg and -0.2+/-1.3 kg, respectively). CONCLUSIONS: The format of prevention programs may influence the willingness of subjects to participate, as well as treatment outcome. Both format acceptability and efficacy should be considered in determining the overall effectiveness of a program. International Journal of Obesity (2000) 24, 219-225

Adult↗

PubMed2000

A case-control study of successful maintenance of a substantial weight loss: individuals who lost weight through surgery versus those who lost weight through non-surgical means.

OBJECTIVE: To determine if method of weight loss (surgery; non-surgery) is associated with current levels of psychosocial functioning or current weight maintenance behaviors in individuals who have lost large amounts of weight. DESIGN: Subjects were 67 cases and 67 controls selected from the National Weight Control Registry, a longitudinal study of individuals successful at long-term maintenance of weight loss. Cases had initially lost weight through bariatric surgery while controls had lost weight through non-surgical means. The current psychosocial functioning and weight maintenance behaviors of cases and controls were assessed and compared. RESULTS: Cases and controls were matched on gender, current weight and total weight loss. Surgical cases reported significantly higher fat intake and lower physical activity levels. There were no differences in cases' and controls' reports of the impact of weight loss on other areas of their lives, neither were there differences on measures of depression or binge-eating. CONCLUSIONS: Reported improvement in psychosocial functioning did not depend upon how weight was initially lost, but cases and controls appear to be using very different behaviors to maintain their weight losses.

Adult↗

PubMed2000

Binge antecedents in obese women with and without binge eating disorder.

In this study, women with binge eating disorder (BED; n = 41) and weight- and age-matched comparison women without BED (NBED; n = 38) monitored their eating for 6 days, using handheld computers to measure mood, appetite, and setting at all eating episodes and comparison noneating episodes. Poor mood, low alertness, feelings of poor eating control, and craving sweets all preceded binge episodes for the BED group. An unanticipated finding was the frequent report of binge episodes in the comparison group; only feelings of poor eating control and craving sweets predicted binge episodes in this group. Binge eating NBED women tended to experience worse mood, less control, and more craving than other NBED women, contributing to evidence of the close relationship of binge eating and decrements in emotional and appetitive functioning.

Adult↗

PubMed1999

Effects of intermittent exercise and use of home exercise equipment on adherence, weight loss, and fitness in overweight women: a randomized trial.

CONTEXT: Enhancing participation in long-term exercise may translate into improved long-term weight loss in overweight adults. OBJECTIVES: To compare the effects of intermittent with traditional continuous exercise on weight loss, adherence, and fitness, and to examine the effect of combining intermittent exercise with that using home exercise equipment. DESIGN: Randomized trial from September 1996 through September 1998. SETTING AND PARTICIPANTS: A total of 148 sedentary, overweight (mean [SD] body mass index, 32.8 [4.0] kg/m2) women (mean [SD] age, 36.7 [5.6] years) in a university-based weight control program. INTERVENTIONS: Eighteen-month behavioral weight control program with 3 groups: long-bout exercise (LB), multiple short-bout exercise (SB), or multiple short-bout exercise with home exercise equipment (SBEQ) using a treadmill. MAIN OUTCOME MEASURES: Body weight, body composition, cardiorespiratory fitness, and exercise adherence. RESULTS: Of 148 subjects, 115 (78%) completed the 18-month program. At 18 months, mean (SD) weight loss was significantly greater in subjects in the SBEQ group compared with subjects in the SB group (-7.4 [7.8] kg vs -3.7 [6.6] kg; P<.05). Mean (SD) weight loss for subjects in the LB group (-5.8 [7.1] kg) was not significantly different than for subjects in the SB or SBEQ groups. Subjects in the SBEQ group maintained a higher level of exercise than subjects in both the SB and LB groups (P<.05) at 13 to 18 months of treatment. All groups showed an increase in cardiorespiratory fitness from baseline to 18 months, with no difference between groups. Mean (SD) weight loss at 18 months was significantly greater in individuals exercising more than 200 min/wk throughout the intervention (-13.1 [8.0] kg) compared with individuals exercising 150 to 200 min/wk (-8.5 [5.8] kg) or less than 150 min/wk (-3.5 [6.5] kg) (P<.05). CONCLUSIONS: Compared with the LB group, subjects in the SB group did not experience improved long-term weight loss, exercise participation, or cardiorespiratory fitness. Access to home exercise equipment facilitated the maintenance of SB, which may improve long-term weight loss. A dose-response relationship exists between amount of exercise and long-term weight loss in overweight adult women.

Adult↗

PubMed1999

Behavioral strategies of individuals who have maintained long-term weight losses.

OBJECTIVE: The purpose of the present study was to compare the behaviors of individuals who have achieved long-term weight loss maintenance with those of regainers and weight-stable controls. RESEARCH METHODS AND PROCEDURES: Subjects for the present study were participants in a random-digit dial telephone survey that used a representative sample of the U.S. adult population. Eating, exercise, self-weighing, and dietary restraint characteristics were compared among weight-loss maintainers: individuals who had intentionally lost > or =10% of their weight and maintained it for > or = 1 year (n = 69), weight-loss regainers: individuals who intentionally lost > or = 10% of their weight but had not maintained it (n = 56), and weight-stable controls: individuals who had never lost > or = 10% of their maximum weight and had maintained their current weight (+/-10 pounds) within the past 5 years (n = 113). RESULTS: Weight-loss maintainers had lost an average of 37 pounds and maintained it for over 7 years. These individuals reported that they currently used more behavioral strategies to control dietary fat intake, have higher levels of physical activity (especially strenuous activity), and greater frequency of self-weighing than either the weight-loss regainers or weight-stable controls. Maintainers and regainers did not differ in reported levels of dietary restraint, but both had higher levels of restraint than the weight-stable controls. DISCUSSION: These results suggest that weight-loss maintainers use more behavioral strategies to control their weight than either regainers or weight-stable controls. It would thus appear that long-term weight maintenance requires ongoing adherence to a low-fat diet and an exercise regimen in addition to continued attention to body weight.

Adult↗

PubMed1999

The behavioral characteristics of individuals who lose weight unintentionally.

OBJECTIVE: To determine whether individuals who unintentionally lost weight differ from individuals who intentionally lost weight in behavioral characteristics related to chronic disease risk factors. DESIGN: A random-digit dial telephone survey was conducted among a representative sample of American adults (n = 500). SUBJECTS: Of the 500 individuals sampled, 139 were currently > or = 10% below their lifetime maximum weight. These individuals were asked whether their weight loss was unintentional or intentional. Unintentional (n =49) and intentional (n = 89) weight losers were compared on measures of dietary intake, physical activity, smoking, drinking, and self-reported health status. RESULTS: Unintentional weight losers had higher levels of smoking and drinking, were less physically active, and were less concerned about their diet and fat intake. Unintentional weight losers did not report having higher levels of disease such as high blood pressure or diabetes. However, unintentional weight losers who reported having such diseases were more likely to report that their weight loss had no effect or had worsened their disorder. DISCUSSION: Compared to intentional weight losers, those who lost their weight unintentionally reported engaging in more negative health behaviors that are related to disease morbidity and mortality. These data suggest that unintentional weight loss may be part of a cluster of behaviors that have a negative health impact.

Adult↗

PubMed1999

Weight loss and leptin changes in individuals with type 2 diabetes.

OBJECTIVE: To identify variables associated with leptin change in subjects with type 2 diabetes after 3 weeks and 20 weeks of weight loss. RESEARCH METHODS AND PROCEDURES: Subjects with type 2 diabetes treated with diet or sulfonylureas (n = 54) were enrolled in a 20-week behavioral weight control program. Sulfonylureas were stopped > or =2 weeks before study entry. Seven subjects who restarted sulfonylureas after week 3 had their data analyzed separately after this point. RESULTS: Leptin, fasting plasma glucose, and insulin levels were measured at baseline and at 3, 10, and 20 weeks. After 3 weeks, subjects lost 2.7+/-2.0 kg (p<0.001), and had significant decreases in leptin (5.2+/-7.0 ng/mL, p<0.001), fasting plasma glucose (1.8+/-1.8 mmol/L, p<0.001), and insulin (23+/-60 pmol/L, p<0.03). Between week 3 and week 20, subjects lost an additional 6.3+/-4.4 kg (p<0.001), but had no further changes in leptin. The primary determinants of leptin change at all time-points were weight loss and initial leptin level. Changes in insulin were not related to changes in leptin after controlling for the effects of weight loss. At week 20, more recent weight loss (week 10 to week 20) was as strong a predictor of overall change in leptin as overall weight loss (baseline to 20 week). Subjects who restarted sulfonylureas had an increase in both leptin levels (+1.9+/-9.0 ng/mL, p<0.05) and insulin levels (+23+/-65 pmol/L, p<0.05), despite significant overall weight loss (-7.4+/-4.0 kg, p<0.01). Initial changes in leptin (0 weeks to 3 weeks) did not affect subsequent ability to lose weight. DISCUSSION: Both short- and long-term changes in weight had an effect on leptin changes in individuals with type 2 diabetes. Although physiological insulin changes did not independently influence changes in leptin concentration with weight loss, increases in insulin levels with sulfonylurea therapy were associated with increases in leptin levels despite weight loss.

Adult↗

PubMed1999

Benefits of recruiting participants with friends and increasing social support for weight loss and maintenance.

To determine the benefits of social support for weight loss and maintenance, this study recruited participants (N = 166) either alone or with 3 friends or family members and then randomly assigned them to a standard behavioral treatment (SBT) or SBT with social support strategies. Participants recruited with friends had greater weight losses at the end of the 4-month treatment and at Month 10 follow-up. Both recruitment strategy and the social support manipulation affected treatment completion and weight-loss maintenance. In those recruited alone and given SBT, 76% completed treatment and 24% maintained their weight loss in full from Months 4 to 10. Among those recruited with friends and given SBT plus social support, 95% completed treatment and 66% maintained their weight loss in full.

Adult↗

PubMed1999

What predicts weight regain in a group of successful weight losers? .

This study identified predictors of weight gain versus continued maintenance among individuals already successful at long-term weight loss. Weight, behavior, and psychological information was collected on entry into the study and 1 year later. Thirty-five percent gained weight over the year of follow-up, and 59% maintained their weight losses. Risk factors for weight regain included more recent weight losses (less than 2 years vs. 2 years or more), larger weight losses (greater than 30% of maximum weight vs. less than 30%), and higher levels of depression, dietary disinhibition, and binge eating levels at entry into the registry. Over the year of follow-up, gainers reported greater decreases in energy expenditure and greater increases in percentage of calories from fat. Gainers also reported greater decreases in restraint and increases in hunger, dietary disinhibition, and binge eating. This study suggests that several years of successful weight maintenance increase the probability of future weight maintenance and that weight regain is due at least in part to failure to maintain behavior changes.

Adult↗

PubMed1999

Binge status as a predictor of weight loss treatment outcome.

OBJECTIVE: A widely held clinical belief is that individuals with binge eating problems fare poorly in weight loss programs. The empirical evidence regarding the prognostic significance of binge eating, however, is mixed. The goals of this study were to examine psychological and behavioral characteristics associated with binge eating and the prognostic significance of binge eating for short- and long-term weight loss in a large sample of women treated for obesity. DESIGN: The dataset used in the current study was a combined sample of women (n = 444) who participated in one of three behavioral weight loss research studies. MATERIALS AND METHOD: Measures of dieting and weight history were obtained at baseline. Body weight, the Binge Eating Scale (BES), a measure of perceived barriers to weight loss, the Beck Depression Inventory, the Block Food Frequency Questionnaire, and the Paffenbarger Physical Activity Questionnaire were assessed at baseline, 6 months and 18 months. Regression analyses examined cross-sectional associations between the BES and the other variables at baseline, prospective associations between baseline BES and changes in weight and the psychological and behavioral variables over time, and temporal covariations between BES and the other variables over time. RESULTS: Cross-sectional analyses showed baseline binge eating status to be strongly associated with dieting history, weight cycling, depressive symptomatology and perceived barriers to weight loss. Women with binge eating problems were also more likely to drop out of treatment. Baseline binge status was not associated with 6-month weight loss, but was weakly predictive of less weight loss success at 18 months. Binge status at baseline did not predict changes in dietary intake, physical activity, perceived barriers to weight loss or depressive symptomatology at either 6 months or 18 months. In time-dependent covariance analyses, changes in BES scores were significantly associated with changes in body weight, independent of changes in dietary intake and physical activity. However, when depression scores are included in the analysis, the association between binge score and body weight was no longer statistically significant. CONCLUSION: These findings suggest that baseline binge status was a weak prognostic indicator of success in women who are moderately obese and are seeking treatment for weight loss. Although assessments of binge status covary with weight loss and regain, the relationship appears to be mediated by psychological dysphoria.

Adult↗

PubMed1999

The prevalence of weight loss maintenance among American adults.

BACKGROUND: Previous studies suggest that few individuals achieve long-term weight loss maintenance. Because most of these studies were based on clinical samples and focused on only one episode of weight loss, these results may not reflect the actual prevalence of weight loss maintenance in the general population. DESIGN: A random digit dial telephone survey was conducted to determine the point prevalence of weight loss maintenance in a nationally representative sample of adults in the United States. Weight loss maintainers were defined as individuals who, at the time of the survey, had maintained a weight loss of > or =10% from their maximum weight for at least 1 y. The prevalence of weight loss maintenance was first determined for the total group (n = 500), and then for the subgroup of individuals who were overweight (body mass index BMI > or =27 kg/m2 at their maximum (n = 228). RESULTS: Weight loss was quite common in this sample: 54% of the total sample and 62% of those who were ever overweight reported that they had lost > or =10% of their maximum weight at least once in their lifetime, with approximately one-half to two-thirds of these cases being intentional weight loss. Among those who had achieved an intentional weight loss of > or =10%, 47-49% had maintained this weight loss for at least 1 y at the time of the survey; 25-27% had maintained it for 5 y or more. Fourteen percent of all subjects surveyed and 21% of those with a history of obesity were currently 10% below their highest weight, had reduced intentionally, and had maintained this 10% weight loss for at least 1 y. CONCLUSIONS: A large proportion of the American population has lost > or =10% of their maximum weight and has maintained this weight loss for at least 1 y. These findings are in sharp contrast to the belief that few people succeed in long-term weight loss maintenance.

Adult↗

PubMed1999

Resting energy expenditure in reduced-obese subjects in the National Weight Control Registry.

BACKGROUND: Weight loss in obese subjects is associated with a reduction in resting metabolic rate (RMR). Whether the reduction can be explained solely by a reduction in lean body mass remains controversial. OBJECTIVE: Our objective was to determine whether the reduction in RMR after weight loss was proportional to the decrease in lean mass alone or was greater than could be explained by body composition. DESIGN: We measured the RMR, fasting respiratory quotient (RQ), and body composition in 40 reduced-obese subjects [ie, 7 men and 33 women who had lost > or = 13.6 kg (30 lb) and maintained the loss for > or = 1 y] enrolled in the National Weight Control Registry and 46 weight-matched control subjects (9 men, 37 women). RESULTS: A stepwise multiple regression found lean mass, fat mass, age, and sex to be the best predictors of RMR in both groups. After adjusting RMR for these variables, we found no significant difference in RMR (5926 +/- 106 and 6015 +/- 104 kJ/d) between the 2 groups (P = 0.35). When we adjusted fasting RQ for percentage body fat and age, the reduced-obese group had a slightly higher (0.807 +/- 0.006) RQ than the control group (0.791 +/- 0.005, P = 0.05). This may have been due to the consumption of a diet lower in fat or to a reduced capacity for fat oxidation in the reduced-obese group. CONCLUSION: These results show that in at least some reduced-obese individuals there does not seem to be a permanent obligatory reduction in RMR beyond the expected reduction for a reduced lean mass.

Basal Metabolism↗

PubMed1999

The accuracy of the TriTrac-R3D accelerometer to estimate energy expenditure.

PURPOSE: This study examined the reliability and validity of the TriTrac-R3D triaxial accelerometer to estimate energy expenditure during various modes of exercise. METHODS: Twenty subjects (age = 21.5+/-3.4 yr; body mass index = 23.3+/-3.6 kg x m(-2)) performed five exercises (treadmill walking, treadmill running, stepping, stationary cycling, and slideboard), with each lasting 20-30 min and workload increased at 10-min intervals. To test the inter-TriTrac reliability, two TriTrac-R3D accelerometers were worn during each exercise period, and to examine validity, a simultaneous measurement of energy expenditure was made using indirect calorimetry (SensorMedics 2900 Metabolic Cart). RESULTS: Results showed a significant correlation between the two TriTrac-R3D accelerometers during all exercises. The difference in estimated energy expenditure between the two accelerometers during the walking, stepping, and slideboard exercises was less than 1 kcal x min(-1) but statistically significant (P<0.05). There was also a significant correlation between energy expenditure estimated by each of the TriTrac-R3D accelerometers and indirect calorimetry during walking, running, stepping, and slideboard exercise (P<0.05). The interaction of Method x Workload was significant (P<0.05) for each exercise, indicating that the TriTrac-R3D underestimates energy expenditure and that the magnitude of this underestimation increases as workload increases. CONCLUSIONS: Therefore, energy expenditure estimated via triaxial accelerometry does not increase with increasing workloads. These results suggest that there are limitations to using triaxial accelerometry to quantify energy expenditure.

Adolescent↗