Effects of active video games on body composition: a randomized controlled trial

BACKGROUND: Sedentary activities such as video gaming are independently associated with obesity. Active video games, in which players physically interact with images on screen, may help increase physical activity and improve body composition.

OBJECTIVE: The aim of this study was to evaluate the effect of active video games over a 6-mo period on weight, body composition, physical activity, and physical fitness.

DESIGN: We conducted a 2-arm, parallel, randomized controlled trial in Auckland, New Zealand. A total of 322 overweight and obese children aged 10-14 y, who were current users of sedentary video games, were randomly assigned at a 1:1 ratio to receive either an active video game upgrade package (intervention, n = 160) or to have no change (control group, n = 162). The primary outcome was the change from baseline in body mass index (BMI; in kg/m(2)). Secondary outcomes were changes in percentage body fat, physical activity, cardiorespiratory fitness, video game play, and food snacking.

RESULTS: At 24 wk, the treatment effect on BMI (-0.24; 95% CI: -0.44, -0.05; P = 0.02) favored the intervention group. The change (±SE) in BMI from baseline increased in the control group (0.34 ± 0.08) but remained the same in the intervention group (0.09 ± 0.08). There was also evidence of a reduction in body fat in the intervention group (-0.83%; 95% CI: -1.54%, -0.12%; P = 0.02). The change in daily time spent playing active video games at 24 wk increased (10.03 min; 95% CI: 6.26, 13.81 min; P < 0.0001) with the intervention accompanied by a reduction in the change in daily time spent playing nonactive video games (-9.39 min; 95% CI: -19.38, 0.59 min; P = 0.06).

CONCLUSION: An active video game intervention has a small but definite effect on BMI and body composition in overweight and obese children.

Does maternal concern about children's weight affect children's body size perception at the age of 6.5? A community-based study

OBJECTIVE: Though overweight is often established by school entry, not all mothers of such children report weight concerns. Enhancing concern might assist lifestyle change, but could lead to child body dissatisfaction. We investigated (i) perceived/desired body size and body dissatisfaction in mothers and their 6.5-year-old children, and (ii) the impact of earlier maternal concern about overweight on children's body mass index (BMI) status and body dissatisfaction. DESIGN: Prospective community study. SETTING: Melbourne, Australia. SUBJECTS: 317 mother-child dyads. MAIN EXPOSURES: Child and maternal BMI (kg m(-2)) at 4.0 and 6.5 years; maternal concern about child overweight at 4.0 years. OUTCOME MEASURES: Paired perceived and desired body size on 7-point figural rating scales self-reported by mothers and children, and reported by mothers regarding children; dissatisfaction ('desired' minus 'perceived') score. RESULTS: For all three actual BMI perceived size pairings (mother self-report, mother's report on child and child self-report), BMI correlated with perceived body size (r=0.82 (mother self-report); r=0.65 (mother reporting on child); r=0.22 (child self-report); all P<0.001). Similarly, all three dissatisfaction scores were greater with increasing BMI status. Children's own dissatisfaction scores correlated with their actual BMI, but were not related to mothers' own body dissatisfaction scores or with mothers' dissatisfaction with children's body size. Maternal concern about overweight at the age of 4 years was not associated with BMI change, or child body dissatisfaction by the age of 6.5. Most mothers of overweight and obese children (88 and 90%, respectively) regarded their child as the middle figure (that is, 4) or thinner. CONCLUSIONS: Despite low rates of recognition of child overweight, maternal perceptions of the child's body correlated strongly with the child's actual BMI. Maternal concerns about child BMI did not appear to impact on child BMI change or child body dissatisfaction.

Fat mass- and obesity-associated genotype, dietary intakes and anthropometric measures in European adults: the Food4Me study

The interplay between the fat mass- and obesity-associated (FTO) gene variants and diet has been implicated in the development of obesity. The aim of the present analysis was to investigate associations between FTO genotype, dietary intakes and anthropometrics among European adults. Participants in the Food4Me randomised controlled trial were genotyped for FTO genotype (rs9939609) and their dietary intakes, and diet quality scores (Healthy Eating Index and PREDIMED-based Mediterranean diet score) were estimated from FFQ. Relationships between FTO genotype, diet and anthropometrics (weight, waist circumference (WC) and BMI) were evaluated at baseline. European adults with the FTO risk genotype had greater WC (AA v. TT: +1·4 cm; P=0·003) and BMI (+0·9 kg/m2; P=0·001) than individuals with no risk alleles. Subjects with the lowest fried food consumption and two copies of the FTO risk variant had on average 1·4 kg/m2 greater BMI (Ptrend=0·028) and 3·1 cm greater WC (Ptrend=0·045) compared with individuals with no copies of the risk allele and with the lowest fried food consumption. However, there was no evidence of interactions between FTO genotype and dietary intakes on BMI and WC, and thus further research is required to confirm or refute these findings.

Fat mass is associated with foot pain in men: the Geelong osteoporosis study

OBJECTIVE: Foot pain is a common complaint in adults. Evidence suggests that body composition is involved in the development of foot pain. However, whether this is the case in men remains unclear because previous studies mainly examined women. The aim of this cross-sectional study was to determine the relationship between body composition and foot pain in men while accounting for important risk factors. METHODS: Among 978 men (median age 60 yrs, range 24-98) from the Geelong Osteoporosis Study who participated in a followup study in 2006 to 2011, 796 provided responses to questions on health status and foot pain. Foot pain was determined using the Manchester Foot Pain and Disability Index, and body composition was measured using dual-energy x-ray absorptiometry. RESULTS: Of the 796 respondents, 177 (22%) had foot pain. Risk factors for foot pain were age (OR 1.03, 95% CI 1.02-1.04), self-reported depression (OR 2.05, 95% CI 1.30-3.20), decreased mobility (OR 1.54, 95% CI 1.05-2.24), and lower education (OR 1.47, 95% CI 1.03-2.09). Foot pain was associated with body mass index (OR 1.05, 95% CI 1.00-1.10), fat mass (OR 1.02, 95% CI 1.03-1.05), and fat mass index (OR 1.08, 95% CI 1.01-1.15), but not fat-free mass (OR 1.01, 95% CI 0.98-1.04) or fat-free mass index (OR 1.05, 95% CI 0.95-1.15) after appropriate adjustments were made. CONCLUSION: Fat mass is associated with foot pain in men. These findings complement those in studies that have mainly examined women, and provide further evidence for the relationship between obesity and foot pain.

Exploring the dietary patterns of young New Zealand women and associations with BMI and body fat

Examining dietary patterns provides an alternative approach to investigating dietary behaviors related to excess adiposity. The study aim was to investigate dietary patterns and body composition profiles of New Zealand European (NZE) women, participating in the women’s EXPLORE (Examining the Predictors Linking Obesity Related Elements) study. Post-menarche, pre-menopausal NZE women (16-45 years) (n = 231) completed a validated 220-item, self-administrated, semi-quantitative food frequency questionnaire. Body mass index (BMI) was calculated using measured height (cm) and weight (kg); body fat percentage (BF%) was measured using air displacement plethysmography (BodPod). Dietary patterns were identified using principal component factor analysis. Associations between dietary patterns, age, BMI and BF% were investigated. Four dietary patterns were identified: snacking; energy-dense meat; fruit and vegetable; healthy, which explained 6.9%, 6.8%, 5.6% and 4.8% of food intake variation, respectively. Age (p = 0.012) and BMI (p = 0.016) were positively associated with the “energy-dense meat” pattern. BF% (p = 0.016) was positively associated with the “energy-dense meat” pattern after adjusting for energy intake. The women following the identified dietary patterns had carbohydrate intakes below and saturated fat intakes above recommended guidelines. Dietary patterns in NZE women explain only some variations in body composition. Further research should examine other potential factors including physical activity and socioeconomic status.

Genetic variation and obesity in Australian women: A prospective study.

Objective: A number of candidate genes have been implicated in the pathogenesis of obesity in humans. This study examines associations between longitudinal changes in body mass and composition and the presence of polymorphisms in the ß-3 adrenergic receptor, tumor necrosis factor-α, leptin, and leptin receptor (Lepr) in a cohort of Australian women.

Research Methods and Procedures: Healthy white Australian women (n = 335) were randomly selected from the Barwon region of Victoria and underwent baseline anthropometry and double-energy X-ray absorptiometry for assessment of body mass and adiposity. These measurements were repeated again at 2-year follow-up. Genomic DNA was extracted and used for polymerase chain reaction-based genotyping of all polymorphisms.

Results: The Pro1019Pro Lepr polymorphism was associated with longitudinal increases in body weight (p = 0.02), fat mass (p = 0.05), and body mass index (p = 0.01) in this study, and individuals homozygous for the A allele at this locus had a greater propensity to gain body fat over time. The largest effects on body composition seemed to be in individuals already obese at baseline. Changes in body weight, fat mass, percent body fat, and body mass index over a 2-year period were not associated with genetic variation in the ß-3 adrenergic receptor (Trp64Arg), tumor necrosis factor-α promoter, or leptin genes in non-obese or obese women.

Discussion: These results suggest that a Lepr polymorphism is involved in the regulation of body mass and adiposity in obese Australian white women, which may have implications for the treatment of obesity in this population.

Which aspects of socioeconomic status are related to obesity among men and women?

OBJECTIVE: This study aimed to investigate the relationships between body weight and fat distribution, and four empirically derived domains of socioeconomic status: employment, housing, migration status and family unit.

DESIGN: A population-based study was used.

PARTICIPANTS: A total of 8667 randomly-selected adults (4167 men; 4500 women) who participated in the 1995 Australian National Health and Nutrition Surveys provided data on a range of health factors including objective height, weight and body fat distribution, and a range of sociodemographic indicators.

RESULTS: Results demonstrated associations for women, after controlling for age, between the employment domain, and body mass index and waist-to-hip ratio. Low status employed women were 1.4 times as likely to be overweight as high status employed women. There were less consistent relationships observed among these factors for men. Relationships between family unit and indicators of body weight and body fat distribution were observed for both men and women, with those who were married, particularly men (OR=1.6, 95% CI 1.4-2.0), at higher risk of overweight. The migration and housing socioeconomic status domains were not consistently associated with body mass index or waist-to-hip ratio.

CONCLUSIONS: These findings indicate that different components of socioeconomic status may be important in predicting obesity, and thus should be examined separately. Future research would benefit from investigating the underlying mechanisms governing the relationships between socioeconomic status domains further, particularly those related to employment and family unit and obesity

Who does not gain weight? Prevalence and predictors of weight maintenance in young women

OBJECTIVE: To investigate the prevalence and predictors of weight maintenance over time in a large sample of young Australian women.

DESIGN: This population study examined baseline and 4 y follow-up data from the cohort of young women participating in the Australian Longitudinal Study on Women's Health.

SUBJECTS: A total of 8726 young women aged 18-23 y at baseline.

MEASURES: Height, weight and body mass index (BMI); physical activity; time spent sitting; selected eating behaviours (eg dieting, disordered eating, takeaway food consumption); cigarette smoking, alcohol consumption; parity; and sociodemographic characteristics.

RESULTS: Only 44% of the women reported their BMI at follow-up to be within 5% of their baseline BMI (maintainers); 41% had gained weight and 15% had lost weight. Weight maintainers were more likely to be in managerial or professional occupations; to have never married; to be currently studying; and not to be mothers. Controlling for sociodemographic factors, weight maintainers were more likely to be in a healthy weight range at baseline, and to report that they spent less time sitting, and consumed less takeaway food, than women who gained weight.

CONCLUSIONS: Fewer than half the young women in this community sample maintained their weight over this 4 y period in their early twenties. Findings of widespread weight gain, particularly among those already overweight, suggest that early adulthood, which is a time of significant life changes for many women, may be an important time for implementing strategies to promote maintenance of healthy weight. Strategies which encourage decreased sitting time and less takeaway food consumption may be effective for encouraging weight maintenance at this life stage.

Exercise training increases lipid metabolism gene expression in human skeletal muscle

The effects of a single bout of exercise and exercise training on the expression of genes necessary for the transport and beta -oxidation of fatty acids (FA), together with the gene expression of transcription factors implicated in the regulation of FA homeostasis were investigated. Seven human subjects (3 male, 4 female, 28.9 ± 3.1 yr of age, range 20-42 yr, body mass index 22.6 kg/m², range 17-26 kg/m²) underwent a 9-day exercise training program of 60 min cycling per day at 63% peak oxygen uptake (V_{O2 peak}; 104 ± 14 W). On days 1 and 9 of the program, muscle biopsies were sampled from the vastus lateralis muscle at rest, at the completion of exercise, and again 3 h postexercise. Gene expression of key components of FA transport [FA translocase (FAT/CD36), plasma membrane-associated FA-binding protein], beta -oxidation [carntine palmitoyltransferase(CPT) I, beta -hydroxyacyl-CoA dehydrogenase] and transcriptional control [peroxisome proliferator-activated receptor (PPAR)alpha , PPARgamma , PPARgamma coactivator 1, sterol regulatory element-binding protein-1c] were unaltered by exercise when measured at the completion and at 3 h postexercise. Training increased total lipid oxidation by 24% (P < 0.05) for the 1-h cycling bout. This increased capacity for lipid oxidation was accompanied by an increased expression of FAT/CD36 and CPT I mRNA. Similarly, FAT/CD36 protein abundance was also upregulated by exercise training. We conclude that enhanced fat oxidation after exercise training is most closely associated with the genes involved in regulating FA uptake across the plasma membrane (FAT/CD36) and across the mitochondrial membrane (CPT I).

Social comparisons and negative affect as indicators of problem eating and muscle preoccupation among children

The present study examined the utilization of social comparison practices and the role of negative affect in predicting body dissatisfaction, problem eating, and muscle preoccupation among young children. Participants were 236 children aged between 8 and 10 years. Children's eating, exercising, and muscle concerns were examined using a modified version of the Children's Eating Attitudes Test (ChEAT), which included additional items pertaining to muscle bulk and exercising. Consistent with past findings, body mass index (BMI) was found to be the sole unique indicator of body dissatisfaction for both boys and girls. Utilization of social comparison practices with adults was the main unique indicator of the modified ChEAT factors for boys, while BMI was the main unique indicator of the modified ChEAT factors for girls. In addition, negative affect was associated with binging, food preoccupation, and social pressure to eat for boys and dieting and muscle preoccupation for girls. Findings are discussed in relation to previous studies with adolescents and adults.

The taq IA and Ser311Cys polymorphisms in the dopamine D2 receptor gene and obesity

Dopamine D2 receptors (DRD2) in the central nervous system are involved in the regulation of feeding. It remains to be elucidated if mutations in the DRD2 gene contribute to the development of obesity. The aim of the present study was to investigate whether the Taq IA and Ser311Cys polymorphisms in the DRD2 gene are associated with obesity in Nauruan and Australian subjects. Subjects were selected based on extremes of the body mass index (BMI) distribution. Two groups of Australian women were selected. The leanest group had a mean BMI of 22.5 kg/m2 (range: 20.3-24.3) and the heaviest group had a mean of 36.1 kg/m2 (32.5-44.1). Four groups of Nauruan subjects were selected. Leanest men had a mean BMI of 33.0 kg/m2 (28.4-36.9), heaviest men had a mean of 52.8 kg/m2 (46.5-69.2), leanest women had a mean of 34.8 kg/m2 (28.2-41.8) and heaviest women had a mean of 55.1 kg/m2 (49.3-73.8). Subjects were genotyped for the Taq IA and Ser311Cys polymorphisms using polymerase chain reaction (PCR) restriction fragment length polymorphism analysis and allelic discrimination TaqmanTM PCR respectively. Leanest and heaviest groups were examined for differences in genotype frequency. Taq IA and Ser311Cys genotype frequencies did not differ significantly between leanest and heaviest Nauruan groups, or between leanest and heaviest Australians. Haplotype frequencies of these polymorphisms did not differ between leanest and heaviest groups. The Taq IA and Ser311Cys polymorphisms in the DRD2 gene are unlikely to be common causes of obesity in these populations.

Social factors and obesity: an investigation of the role of health behaviours

OBJECTIVES: This study evaluated a behavioural model of the relation between social factors and obesity, in which differences in body mass index (BMI) across sociodemographic groups were hypothesized to be attributable to social group differences in health behaviours affecting energy expenditure (physical activity, diet and alcohol consumption and weight control).

METHODS: A total of 8667 adults who participated in the 1995 Australian National Health and Nutrition Surveys provided data on a range of health factors including objectively measured height and weight, health behaviours, and social factors including family status, employment status, housing situation and migration status.

RESULTS: Social factors remained significant predictors of BMI after controlling for all health behaviours. Neither social factors alone, nor health behaviours alone, adequately explained the variance in BMI. Gender-specific interactions were found between social factors and individual health behaviours.

CONCLUSIONS: These results suggest that social factors moderate the relation between BMI and weight-related behaviours, and that the mechanisms underlying sociodemographic group differences in obesity may vary among men and women. Additional factors are likely to act in conjunction with current health behaviours to explain variation in obesity prevalence across sociodemographic groups.

Public definitions of success in weight management

Objective: To examine perceptions of success in weight control and future weight-control intentions in a community sample. Design: Cross-sectional postal survey. Subjects: There were 1500 adults randomly selected from the Electoral Roll of Victoria (47% response). Setting: Community. Main outcome measures: Retrospective weight change over previous 12 months; perceived weight-control success; future weight-control intentions. Statistical analyses: Pearson's χ² tests were used to compare perceived weight-control success by sex, and by age, education level, initial BMI, amount of weight change and weight-loss behaviour within sex. ANOVA was used to compare mean weight change associated with perceived weight control success within sex, and within age, education, body mass index and weight-loss behaviour by sex. The distribution (frequency) of weight-control intentions are reported within perceived weight-control success and amount of weight change. Results: One in two (53%) reported maintaining their weight within 1kg in the preceding 12 months, 26% of men and 21% of women reported weight gain and 20% of men and 26% of women reported weight loss. Almost one-third (30%) of those who maintained their weight considered themselves unsuccessful. A majority of those who lost weight considered themselves successful at controlling their weight. However, more than 45% of men who gained weight also considered themselves successful. Those who considered themselves unsuccessful experienced less weight loss (1.1 ± 3.9kg) than those who considered themselves quite successful (-1.4 ± 4.5 kg, P < 0.001) or very successful (-1.3 ± 7.8 kg, P < 0.001). Conclusion: Public views of what constitutes successful weight control may need to be reoriented to be consistent with public health goals.

A biopsychosocial model of disordered eating and the pursuit of muscularity in adolescent boys

This review provides an evaluation of the correlates and/or risk factors associated with disordered eating and the pursuit of muscularity among adolescent boys. One of the main conclusions is that similar factors and processes are associated with both behavioral problems. Several factors found to be consistently associated with disordered eating among boys are also similar to those found with girls. These include body mass index, negative affect, self-esteem, perfectionism, drug use, perceived pressure to lose weight from parents and peers, and participation in sports that focus on leanness. However, as many of the findings have only been verified using cross-sectional designs, prospective studies are now needed. (PsycINFO Database Record (c) 2008 APA, all rights reserve

An investigation into the incidence of obesity and underweight among adults with an intellectual disability in an Australian sample

Reports suggest that 7% to 18% of Australian adults are obese and a further 16% to 55% are overweight. Studies from other countries have indicated that obesity among people with an intellectual disability may be at least, or even more, prevalent. Prevalence rates range from 28% to 59%. The aim of the current study was to investigate the weight distribution of an Australian sample of people with an intellectual disability using Body Mass Index (BMI) to classify males and females, and Kelly and Rimmer's (1987) Percentage of Body Fat (PBF) formula to also classify males. Forty-one females and 52 males with a mild to severe intellectual disability were assessed. The correlation between BMI and PBF for males was r=.89. BMI classifications revealed a higher percentage of females as overweight (41.4%) and obese (36.6%) compared to overweight males (30.8%) and obese males (30.8%). There were more underweight males (7.6%) than females (4.9%). There was no relationship between living environment and weight classifications on the BMI. The PBF formula indicated that 73% of the males were classified as obese. The possibility of misclassification using the BMI and the need for weight interventions are discussed.