Does physical activity prevent weight gain--a systematic review

Obesity treatment-associated transfer of exercise-related self-regulation to eating-related self-regulation changes in women

Obesity in the United States has risen to 42 percent of its adult population and is similarly problematic in many other countries. Although the U.S. government has provided education on healthy eating and the need to exercise regularly, behavioral obesity treatments have largely failed to sustain reductions in weight. Self-regulation, and the incorporation of exercise for its psychological impacts on eating, has sometimes been targeted. While there has been sporadic investigation into the carry-over of exercise-related self-regulation to eating-related self-regulation, the present aim is to further inquiry in that area to inform future treatment content for improved effects. Women enrolled in community-based obesity treatments with either a self-regulation (n = 106) or education (n = 54) focus were assessed on changes in exercise- and eating-related self-regulation, negative mood, completed exercise, and weight. Improvements were significantly greater in the self-regulation-focused group. After controlling for initial change in eating-related self-regulation, change in that measure from Month 3 to 6 was significantly predicted by change in exercise-related self-regulation during the initial 3 treatment months. This suggested a carry-over effect. A stronger predictive relationship was associated with the self-regulation-focused treatment. In further analyses, paths from changes in exercise→negative mood→self-regulation of both exercise and eating were significant. Increase in eating-related self-regulation was significantly associated with weight loss over 6, 12, and 24 months. The self-regulation-focused group had stronger relationships, again. Findings suggested utility in targeting exercise-related self-regulation to impact later change in eating-related self-regulation, and the use of exercise-associated mood improvement to bolster participants' self-regulation capabilities.

The relationship between attitude toward physical activity and weight gain in children and young adolescence

Introduction

The purpose of this study was to investigate the association between attitudes toward physical activity and weight gain among children and young adolescents with an additional focus on the impact of gender on these attitudes.

Methods

Employing a descriptive survey method, data were systematically gathered via purposive sampling from 11 specific cities in Türkiye, ensuring representation from all seven regions. A total of 3,138 students, aged between 9 and 14 years, participated in this study, with a distribution of 46% girls and 54% boys. To assess the attitudes of children and young adolescents toward physical activity, the Youth Physical Activity Attitude Scale was utilized. Height and body weight measurements were taken to determine the body mass index of participants. SPSS 26.0 software facilitated the statistical analyses, including Pearson correlation analysis to explore relationships between variables. Multivariate Analysis of Variance was employed to evaluate the impact of age, BMI, and gender on attitudes toward physical activity.

Results

Participants classified as normal weight exhibited a more positive attitude towards physical activity compared to their obese and overweight counterparts. Moreover, a significant gender difference emerged, with boys demonstrating significantly higher positive attitudes toward physical activity than girls. However, no significant difference was observed in negative attitudes based on gender. The study also revealed that an escalation in negative attitudes towards physical activity correlated with students being categorized as underweight, overweight, or obese, as opposed to having a normal weight status. Additionally, a statistically significant divergence in both positive and negative attitudes towards physical activity was found based on age. Specifically, the results indicated that students aged 9 and 14 exhibited lower levels of positive attitude when contrasted with their counterparts of different age groups. Conversely, in the domain of negative attitudes, students at the age of 9 scored higher than their peers in other age categories.

Discussion

Attitudes towards physical activity can serve as a convenient indicator and guide for assessing the effectiveness of various practices or interventions aimed at promoting physical activity, with recognition of the significant gender difference in positive attitudes among children and young adolescents.

Effectiveness of an Artificial Intelligence-Assisted App for Improving Eating Behaviors: Mixed Methods Evaluation

BACKGROUND

A plethora of weight management apps are available, but many individuals, especially those living with overweight and obesity, still struggle to achieve adequate weight loss. An emerging area in weight management is the support for one's self-regulation over momentary eating impulses.

OBJECTIVE

This study aims to examine the feasibility and effectiveness of a novel artificial intelligence-assisted weight management app in improving eating behaviors in a Southeast Asian cohort.

METHODS

A single-group pretest-posttest study was conducted. Participants completed the 1-week run-in period of a 12-week app-based weight management program called the Eating Trigger-Response Inhibition Program (eTRIP). This self-monitoring system was built upon 3 main components, namely, (1) chatbot-based check-ins on eating lapse triggers, (2) food-based computer vision image recognition (system built based on local food items), and (3) automated time-based nudges and meal stopwatch. At every mealtime, participants were prompted to take a picture of their food items, which were identified by a computer vision image recognition technology, thereby triggering a set of chatbot-initiated questions on eating triggers such as who the users were eating with. Paired 2-sided t tests were used to compare the differences in the psychobehavioral constructs before and after the 7-day program, including overeating habits, snacking habits, consideration of future consequences, self-regulation of eating behaviors, anxiety, depression, and physical activity. Qualitative feedback were analyzed by content analysis according to 4 steps, namely, decontextualization, recontextualization, categorization, and compilation.

RESULTS

The mean age, self-reported BMI, and waist circumference of the participants were 31.25 (SD 9.98) years, 28.86 (SD 7.02) kg/m2, and 92.60 (SD 18.24) cm, respectively. There were significant improvements in all the 7 psychobehavioral constructs, except for anxiety. After adjusting for multiple comparisons, statistically significant improvements were found for overeating habits (mean -0.32, SD 1.16; P<.001), snacking habits (mean -0.22, SD 1.12; P<.002), self-regulation of eating behavior (mean 0.08, SD 0.49; P=.007), depression (mean -0.12, SD 0.74; P=.007), and physical activity (mean 1288.60, SD 3055.20 metabolic equivalent task-min/day; P<.001). Forty-one participants reported skipping at least 1 meal (ie, breakfast, lunch, or dinner), summing to 578 (67.1%) of the 862 meals skipped. Of the 230 participants, 80 (34.8%) provided textual feedback that indicated satisfactory user experience with eTRIP. Four themes emerged, namely, (1) becoming more mindful of self-monitoring, (2) personalized reminders with prompts and chatbot, (3) food logging with image recognition, and (4) engaging with a simple, easy, and appealing user interface. The attrition rate was 8.4% (21/251).

CONCLUSIONS

eTRIP is a feasible and effective weight management program to be tested in a larger population for its effectiveness and sustainability as a personalized weight management program for people with overweight and obesity.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04833803; https://classic.clinicaltrials.gov/ct2/show/NCT04833803.

Magnitude of vertical ground reaction force during water-based exercises in women with obesity

Individuals with obesity are recommended to practice physical activity with reduced weight bearing, such as water-based exercises. However, the magnitude of the vertical ground reaction force (Fz) during these exercises is unknown in this population. This study aimed to verify the magnitude of peak Fz (Fzpeak) in women with obesity during different exercises performed in water and on land and at different intensities. Ten adult women with obesity class 1 (body mass index: 31.6 ± 0.57 kg·m-2) completed two randomised sessions, one performed on land and other in water, composed by three exercises (stationary running, frontal kick, butt kick) performed at cadences of 80 b·min-1, 100 b·min-1 and maximal. Fzpeak value was determined in each situation. Data were analysed using repeated-measures three-way ANOVA (α = 0.05). Significant lower Fzpeak values were observed in water (p < 0.001), with no significant differences between the exercises. A significant difference in the Fzpeak was verified between maximal cadence and 80 b·min-1 (p = 0.01). Water-based exercises performed by women with obesity revealed a Fzpeak reduction from land to water corresponding to 41-67%. Also, the three water-based exercises resulted in similar Fzpeak values, while an increase was observed 80 b·min-1 to the maximal cadence.

EXERT-BC: A pilot study of an exercise regimen designed to improve functional mobility, body composition, and strength after the treatment for breast cancer

PURPOSE

Resistance training may offer several unique advantages within breast cancer (BC) survivorship care; however, safety concerns have limited the application of high-intensity compound movements necessary to elicit optimal changes in body composition, strength, and quality of life in this population. The EXERT-BC trial assesses the safety and feasibility of an evidence-based, dose-escalated resistance training regimen among BC survivors, with the goal of improving physical and metabolic function, mobility, muscle mass, and body composition.

METHODS

Participants included women with breast cancer underwent a 3-month thrice weekly exercise regimen involving dose escalation of high-intensity compound exercises. Coprimary outcomes included safety and adherence. Pre- and post-regimen assessment included body composition testing, functional mobility and balance, total load (weight × repetitions × sets) across compound exercises, and patient reported quality of life. Pairwise comparison was performed via the paired t test.

RESULTS

Fourty participants completed a 3-month exercise regimen, with a median age of 57 years (range, 27-74 years) and 73% having stage 0-2 BC. BC therapies concurrent with exercise included anti-estrogen therapy (80%), radiotherapy (30%), and non-hormonal systemic therapy (15%). No adverse events were observed aside from a single case of self-limited knee pain. Session attendance exceeded a prespecified threshold of 75%, and 98% patients reported ongoing compliance to an exercise regimen following regimen completion. Significant reductions in percent body fat (p < 0.001) and increases in percent muscle mass (p = 0.011) were observed. Significant increases in resting metabolic rate (p = 0.023), bilateral grip strength (p < 0.001), functional movement screen (p < 0.001), bilateral Y-Balance testing (p < 0.001), and Godin questionnaire scores (p < 0.001) were observed.

CONCLUSION

A 3-month dose-escalated resistance training regimen comprising high-intensity compound movements appears safe with a high degree of adherence among breast cancer survivors, resulting in demonstrable improvements in body composition, metabolic parameters, strength increases, and patient-reported quality of life.

Determining pathways of effect between correlates and outcomes of transport-related physical activity at differing timepoints across the lifecourse: A structural equation modelling approach

Transport-related physical activity levels differ across the lifecourse; however, the nature of these differences is poorly understood. This study examined the relationship between correlates of transport-related physical activity and how they differ in strength, pathway, and direction across the lifecourse. Structural Equation Modelling assessed relationships between correlates (e.g., age, smoking, education) and transport-related physical activity (assessed via the International Physical Activity Questionnaire) at four timepoints of the Australian Childhood Determinants of Adult Health study: childhood (7-15y; n = 6302), early-adulthood (26-36y; n = 2700), early/mid-adulthood (31-41y; n = 1649), and mid-adulthood (36-49y; n = 1794). Several pathways were consistent across the lifecourse. Self-rated health directly associated with transport-related physical activity across all timepoints. During adulthood greater body mass index and smoking frequency were indirectly associated with lower levels of transport-related physical activity via self-rated health; similarly, lower educated adults, who smoked more frequently, and had poorer health, had lower transport-related physical activity. Urban residence was directly associated with greater transport-related physical activity in childhood and early-adulthood; having more children in early/mid- and mid-adulthood was directly associated with less transport-related physical activity. This is the first study to report pathways of direct and indirect association between correlates and transport-related physical activity at key lifecourse stages. The pathways highlighted can inform policy and practice to aid in the development of age-specific lifecourse interventions.

A Systematic Review of eHealth Interventions to Promote Physical Activity in Adults with Obesity or Overweight

Use of information and communication technology to improve health, known as eHealth, is an emerging concept in healthcare that may present opportunities to promote physical activity in adults with obesity. The purpose of this research was to systematically review eHealth intervention studies to promote physical activity in adults with obesity. Five electronic databases were used. Two authors screened articles, assessed risk of bias, and extracted data independently. A qualitative data synthesis for summarizing the findings was performed using harvest plots. In the search, 2276 articles were identified, and 18 studies met all inclusion criteria. Study quality ranged from poor to good. The included studies varied in intervention technology (e.g., web-based), physical activity assessment (e.g., device-based), and control group (e.g., wait-list). Behavioral change techniques used in the included studies were consistent with some techniques (e.g., self-monitoring) known as effective in face-to-face interventions, but more efficiently employed in eHealth using information and communication technology. Overall, this systematic review showed that a web-based or physical activity monitor-based eHealth intervention had the potential to effectively promote physical activity in adults with obesity. Some recommendations for future eHealth interventions to promote physical activity in adults with obesity were provided (e.g., use of theory, accelerometers).

Patterns and Determinants of Weight Gain among People Who Use Drugs Undergoing Treatment for Recovery in Lebanon

Substance use disorder compromises the nutritional status and the eating habits of drug users, often leading to malnutrition. Once referred for treatment, hyperphagia and poor lifestyle practices leading to weight gain are observed. This study aimed to examine the patterns and extent of weight change as well as the determinants of weight gain in a sample of drug users who were receiving treatment in Lebanon. A total of 172 male participants undergoing either rehabilitation or opioid substitution treatment (OST) were included. Multivariate regression analysis was applied to assess the effect of different variables on weight gain while adjusting for potentially confounding variables. Approximately two-thirds (65.1%) of the participants gained weight (OST: 54.3%, rehabilitation: 78.2%; p < 0.05). The mean weight gain was 5.9 kg and was mainly reported among participants in the underweight, normal, and overweight pre-treatment categories and accentuated in the rehabilitation group (OST: 2 kg, Rehabilitation: 10.6 kg). Around half of the participants moved from the normal weight category to the overweight and obese categories during treatment. Weight gain was negatively associated with the number of previous treatment attempts (Odds Ratio = 0.86; Confidence Interval: 0.74-0.99), duration of current treatment (Odds Ratio = 0.98; Confidence Interval: 0.96-0.99), and pre-treatment body mass index (BMI) (Odds Ratio = 0.88; Confidence Interval: 0.80-0.96). Investigating other nutrition and lifestyle practices, neither nutrition knowledge, food addiction, physical activity level, nor sleep quality were associated with weight gain. Treatment through drug use was associated with meaningful weight gain that might lead to health risk factors. Developing health promotion programs is crucial to enhance treatment and decrease the risk of relapse.

Association between physical activity and longitudinal change in body mass index in middle-aged and older adults

BACKGROUND

In middle-aged and particularly older adults, body mass index (BMI) is associated with various health outcomes. We examined associations between physical activity (PA) and longitudinal BMI change in persons aged ≥ 50 years.

METHODS

The sample included 5159 community-dwelling individuals aged ≥ 50 years (50.5% males, mean (SD) age 73.0 (10.2) years at baseline) who were enrolled in the Mayo Clinic Study of Aging (MCSA). Participants had information on PA within one year of baseline assessment, BMI at baseline, and potential follow-up assessments (mean (SD) follow-up 4.6 (3.7) years). Linear mixed-effect models were used to calculate the association between PA (moderate-vigorous physical activity, MVPA; and all PA composite score) and the longitudinal change in BMI, adjusted for baseline age, sex, education and medical comorbidities. In addition to interactions between years since baseline and PA, we also included 2- and 3-way interactions with baseline age to further assess whether age modifies the trajectory of BMI over time.

RESULTS

We observed a decrease in BMI among participants engaging at a mean amount of PA (i.e.

, MVPA

2.7; all PA: 6.8) and with a mean age (i.e., 73 years) at baseline (MVPA: estimate = -0.047, 95% CI -0.059, -0.034; all PA: estimate = -0.047, 95% CI -0.060, -0.035), and this decline is accelerated with increasing age. Participants with a mean age (i.e., 73 years) that engage at an increased amount of MVPA or all PA at baseline (i.e., one SD above the mean) do not decrease as fast with regard to BMI (MVPA: estimate = -0.006; all PA: estimate = -0.016), and higher levels of MVPA or all PA at baseline (i.e., two SD above the mean) were even associated with an increase in BMI (MVPA: estimate = 0.035; all PA: estimate = 0.015). Finally, MVPA but not all PA is beneficial at slowing BMI decline with increasing age.

CONCLUSION

PA, particularly at moderate-vigorous intensity, is associated with slower decline in longitudinal BMI trajectories. This implies that engaging in PA may be beneficial for healthy body weight regulation in middle and late adulthood.

Development and Effect of Child Obesity Management Program by Applied Nudge

BACKGROUND

Child obesity rates are increasing worldwide. In Korea, the proportion of overweight students has steadily increased from 21.8% in 2015 to 25.8% in 2019. Childhood obesity causes mental problems, such as depression and social phobia, due to mental stress, feelings of inferiority, and low self-esteem.

METHODS

This experimental study aimed to verify the effect of the child obesity management program on body changes (height, weight, obesity degree, body mass index [BMI], body fat percentage), eating habits, exercise habits, obesity knowledge, and social support. This child obesity management program applies the nudge technique based on an ecological model and induces autonomous weight management through environmental control.

RESULTS

As results of this study, the child obesity management program using the nudge technique developed in this study improved the height (t = -5.19, p < 0.001), obesity degree (z = -3.28, p = 0.001), BMI (z = -3.22, p = 0.001), exercise habits (t = -2.09, p = 0.040), and obesity knowledge of obese children (z = -2.99, p = 0.003).

CONCLUSIONS

This multidimensional intervention improved obesity by inducing and sustaining behavioral changes in obese children. Therefore, applying the nudge techniques and multidimensional intervention methods based on ecological model are proposed to increase the effectiveness of the health promotion programs.

Exercise and physical performance in older adults with sarcopenic obesity: A systematic review

Background

Sarcopenic obesity is characterized by low muscle mass and high body fat; prevalence increases with age, particularly after age 65 years. For this systematic literature review we searched scientific databases for studies on exercise interventions for improving physical performance in adults with sarcopenic obesity; also, we identified potential gaps in clinical practice guidelines that need to be addressed.

Methods

We followed the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The databases were searched for studies published through November 2021 that measured physical performance in adults with sarcopenic obesity.

Results

Most of the studies applied a strength training protocol in which improvement was noted post-treatment on the Time Chair Rise (TCR), 30-s Chair Stand, and Single Leg Stance (SLS) tests. Discrepancies between the studies were observed when resistance training was combined with or without elastic bands or electromyostimulation, as measured with the Short Physical Performance Battery (SPPB), Physical Performance Test (PPT), Gait Speed, and Timed Up & Go (TUG) test. Post-intervention SPPB, PPT, and gait speed scores showed an increase or maintenance of performance, while TUG test scores were higher according to one study but lower according to another.

Conclusions

Engagement in physical exercise, and resistance training in particular, can improve or maintain physical performance in adults with sarcopenic obesity. Study samples should include more men. A future area of focus should be the impact of different types of training (aerobic, power training, combined modalities). Finally, studies with longer intervention periods and follow-up periods are needed to gain a better understanding of the effectiveness of exercise on physical function in adults with sarcopenic obesity.

Long-Term Parallel Changes of Physical Activity and Body Mass Index in Different Predisposing Risk Trajectories of Obesity

BACKGROUND

The long-term parallel changes of physical activity and body mass index (BMI) in the adult population are still unclear. The present study assessed the association between physical activity and BMI over time, considering obesity risk trajectory groups and sex strata.

METHODS

Total sample of 6897 adults was followed for an average of 12 years. The reliable and validated Iranian version of the Modifiable Activity Questionnaire measured physical activity. After determining the risk clusters in each reexamination using a 2-step cluster analysis, the latent growth curve modeling was used to identify distinct subgroups of individuals following a similar change of risk cluster over time. Latent growth curve modeling estimated the parameters of cross-sectional, prospective, and parallel associations.

RESULTS

Three trajectories were identified, including stable low risk, unstable risk, and stable high risk. The results showed significant increases in BMI (kg/m2/year) for the stable low-risk trajectory group 0.478 (95% confidence interval [CI] 0.444 to 0.513), unstable risk 0.360 (95% CI, 0.324 to 0.396), and those in the stable high-risk trajectory group 0.255 (95% CI, 0.221 to 0.289). In cross-sectional -0.483 kg/m2 (95% CI, -0.836 to -0.129) and parallel -0.93 kg/m2 (95% CI, -1.862 to 0.00) estimations, significant statistical associations were observed in the stable high-risk trajectory group.

CONCLUSIONS

The current results showed that changes in physical activity could slightly affect BMI only in stable high-risk adults.

Patterns of Physical Activity Among Women Incarcerated in Jail

The physical and mental health benefits of physical activity in all populations are well established. In 2019, incarcerated women at a Southwest county jail were observed during "recreation time," a time when physical activity is encouraged, to identify the proportion of women who participated in recreation time and their physical activity levels. During observed recreation times, 28% of women attended; 56% were sedentary, 4% engaged in vigorous physical activity, and approximately 40% walked or performed similarly moderate physical activity. Future research should identify barriers to being physically active while incarcerated, leading to targeted interventions to promote physical activity.

EXPRESS: Does physical weight alter the mental representation of the body? Evidence from motor imagery in obesity

OBJECTIVE

Obesity is a clinical condition that impacts severely the physical body. However, evidence related to the mental representation of the body in action is scarce. The few available studies only focus on avoiding obstacles, rather than participants imagining their own body.

METHOD

To advance knowledge in this field, we assessed the performance of twenty-two individuals with obesity compared to thirty individuals with a healthy weight in two tasks that implied different motor (more implicit vs. more explicit) imagery strategies. Two tasks were also administered to control for visual imagery skills, to rule out confounding factors. Moreover, we measured body uneasiness, through a standard questionnaire, as body image negativity could impact on other body representation components.

RESULTS

Our findings do not show differences in the motor imagery tasks between individuals with obesity and individuals with healthy weight. On the other hand, some differences emerge in visual imagery skills. Crucially, individuals with obesity did report a higher level of body uneasiness.

CONCLUSIONS

Despite a negative body image and visual imagery differences, obesity per se does not impact on the representation of the body in action. Importantly, this result is independent from the level of awareness required to access the mental representation of the body.

Nutritional Status and its Associations with Eating Behavior and Diet Quality among Adult: A Cross-Sectional Study

BACKGROUND: Obesity among adults is a significant public health problem. Diet quality might be influenced by eating behavior and is associated with nutritional status, but research is lacking in obese adults in Indonesia. AIM: The purpose of this study was to investigate the relationship between eating behavior, diet quality, and obesity. METHODS: A cross-sectional study was carried out among 144 respondents (39.6% males and 60.4% females), aged 39.07 ± 5.48 years, who were selected using stratified random sampling from five subdistrict in Malang City, East Java, Indonesia. The eating behavior score was calculated using the Dutch Eating Behavior Questionnaire (DEBQ) and the diet quality using the Diet Quality Index International (DQI-I) from SQ-FFQ. Association of eating behavior, diet quality, and nutritional status was analyzed using logistic regression analysis. RESULTS: The study showed that the prevalence of obesity among female adults was higher (31.9%) than males (18.8%). The female participant had a two-fold higher likelihood of being overweight or obese than the male participant (OR = 2.25, 95% CI: 1.077; 4.071, p < 0.05). The average diet quality score was 57.99 ± 7.26 or 80% from a total score of 100. There was no significant difference in total DQI-I and component scores, including variety, adequacy, moderation, and overall balance across nutritional status and sex, p > 0.005. The poor-diet quality was higher in the overweight and obesity group (43.75 %) than the normal group (16.67%). There was a statistically significant difference of restrained eating with overweight and obesity status (p < 0.05) with OR 2,652 (CI 95% 1.149; 6.119) and female (OR 2.496, CI 95% 1.195; 5.212, p < 0.05). CONCLUSIONS: It can be concluded that obesity was prevalent in female adults, and there is a relationship between obesity and restraint eating among adults. Future studies should examine the causal effects of eating behaviors on quality diet and in the development of obesity.

Physical Activity and Subsequent Change in Body Weight, Composition and Shape: Effect Modification by Familial Overweight

BACKGROUND

Physical activity (PA) has been shown to attenuate the genetic risk of obesity as measured using polygenic risk scores. However, familial obesity history might be an easier predictor. We examined associations between PA and subsequent changes in BMI, body fat percentage (BF%) and waist circumference (WC) among participants with and without adiposity and a familial overweight.

METHODS

In total, 1971 participants from the Danish MONICA cohort were included. Mean differences for 6-year changes in BMI, BF% and WC across PA levels were estimated. Association between walking and biking and subsequent change in adiposity were analysed. Effect modification by familial obesity was assessed by adding product terms to the models.

RESULTS

We observed weak associations between leisure PA level and changes in WC [participants with low PA: 3.4 cm (95%CI: 2.8;4.0), participants with high PA: 2.4 cm (95%CI: 1.8;3.0)], with no evidence of effect modification by familial obesity. We found effect modification in analyses on walking and biking in relation to changes in BMI (P-interaction<0.01) and BF% (P-interaction=0.04), suggesting lower gain with more hours of activity among participants with adiposity and familial overweight.

CONCLUSIONS

The results were modest but suggested that PA, especially walking and biking, may prevent future adiposity.

Relationships between self-management strategies and physical activity and diet quality in women with polycystic ovary syndrome

OBJECTIVE

To determine the relationships of self-management strategies and physical activity (PA) and diet quality in women with PCOS.

METHODS

An online cross-sectional study involving women (n = 501), 18-45 years in the general Australian community with a self-reported PCOS diagnosis. The self-management and lifestyle behaviour questionnaires were completed between August 2017 and March 2018.

RESULTS

Implementation of PA related self-management strategies increased the odds of meeting PA recommendations [Odds ratio (OR): 2.929 (95%CI: 2.172, 3.951), p < 0.001] but had no association with body mass index (BMI) [OR: 0.-0.984 (95%CI: -1.010, 0.959), p = 0.217] nor perception of self weight [OR: 1.382 (95% CI: 0.700, 2.725), p = 0.352]. Nutrition related self-management strategies were inversely associated with BMI [OR: - 0.115 (95%CI: -7.159, -0.980), p = 0.010] but had no association with diet quality [OR: 0.183 (95%CI: -2.328, 2.800), p = 0.855], energy intake [OR: - 0.092 (95%CI: -1204.443, 527.496) p = 0.438] or weight [OR: - 0.034 (95%CI: -4.020, 1.930), p = 0.491].

CONCLUSIONS

PA self-management strategies were associated with meeting PA recommendations. Nutrition strategies were associated with lower BMI but not diet quality, energy intake or weight in women with PCOS.

PRACTICE IMPLICATIONS

Other behaviour change determinants (e.g. education, skills and self-efficacy) should be considered when designing a PCOS lifestyle programme in conjunction with self-management strategies.

Pilot study of tai chi and qigong on body composition, sleep, and emotional eating in midlife/older women

Weight gain and related adverse changes in body composition are prevalent among midlife and older women and contribute to chronic disease (e.g., type 2 diabetes, hypertension, depression). Tai Chi (TC) and Qigong (QG), forms of Meditative Movement, demonstrate improved physical/psychological symptoms and body composition. Using a standardized TC/QG protocol, we explored pre/post intervention differences in percent body fat and factors related to body composition in midlife/older women. In the context of a single-group pilot study, females ages 45-75 (N = 51) enrolled in an 8-week TC/QG intervention. Primary outcome measures of body composition, sleep quality, emotional eating and select secondary outcome psycho-emotional factors (perceived stress, mood state, mindfulness, self-compassion, body awareness) were collected. Change in percent body fat did not reach statistical significance (p = .30, M =  0.35, 95% CI [- 0.32, 1.0]). Sleep quality improved significantly, p = .04, M = - 0.88, 95% CI [-1.71, - 0.04]. Emotional eating changed in the expected direction, but not significantly, p = .08, M =  -0.16, 95% CI [-0.34, 0.02]. Significant differences were found in body awareness, p = .01, M =  0.36, 95% CI [0.08, 0.63] and perceived stress, p = .05, M =  -2.36, 95% CI [-4.76, 0.04]. Preliminary results are promising as results showed improvements in factors related to healthy body composition. Refined research is needed to understand if/how TC/QG may improve body composition among midlife and older women.

Physical activity recommendation by health care providers to adults with and without functional limitations

Adults with functional limitations are more likely to be physically inactive than those without functional limitations, despite evidence that regular physical activity (PA) slows the progression of functional decline. The health care setting provides an opportunity to communicate with patients about positive behavior changes, including increased PA, but there is little information about provider recommendation for PA to adults with functional limitations. This study investigated health care provider recommendation to increase PA among adults with and without functional limitations. Adults (≥18 years) who participated in the 2016 National Health Interview Survey and reported ≥1 primary care encounter within the previous 12 months were included (unweighted n = 23,540; weighted N = 170,004,764). Receipt of PA recommendation and physical functioning limitations were self-reported. Statistical analyses were weighted to account for complex survey sampling design. One-third (35.88%) of adults received a PA recommendation and 19.71% reported functional limitations. Adults who received a PA recommendation were more likely to have a functional limitation than those who did not (28.64% vs. 14.70%; p < 0.001), even after adjusting for covariates and current activity level (aOR = 1.48; 95% CI:1.33,1.65). PA recommendation for those with functional limitations appeared to increase during middle age and peak for adults aged 65-75 years (57.01%) but declined substantially for adults ≥75 years. Only one-third of adults in the United States received PA recommendations. Health care providers recommended PA to approximately half of adults with functional limitations. Continued efforts to leverage health care encounters for behavior change should be explored, particularly for middle aged and older adults.

Changes in leisure time physical activity unrelated to subsequent body weight changes, but body weight changes predicted future activity

Physical activity and obesity are known to be associated. We investigated whether a change in leisure time physical activities (LTPA) predicts a subsequent weight change, or vice versa.We used data from a longitudinal study among Danish adults surveyed in 1983-1984, 1987-1988, and 1993-1994. Between two sequential surveys, the change in LTPA was grouped as no change, became less or more active; the change in body weight was defined as no change, lost or gained of more than one body mass index (BMI) unit.Among 2386 adults, change in LTPA was not associated with subsequent weight change. However, a loss in body weight (BMI change < -1 unit) was associated with subsequent either becoming less [OR = 1.49, 95% CI (1.03-2.15)] or borderline more active [OR = 1.37, 95% CI (0.99-1.90)]. Subgroup analyses showed particularity among females that a loss in body weight was associated with subsequent becoming more active [OR = 1.83, 95% CI (1.15-2.89)].Our results suggest that change in LTPA is unrelated to subsequent weight change, but loss in body weight seems related to subsequent more active among female adults.

Towards a Parsimonious Pathway Model of Modifiable and Mediating Risk Factors Leading to Diabetes Risk

Modifiable risk factors are of interest for chronic disease prevention. Few studies have assessed the system of modifiable and mediating pathways leading to diabetes mellitus. We aimed to develop a pathway model for Diabetes Risk with modifiable Lifestyle Risk factors as the start point and Physiological Load as the mediator. As there are no standardised risk thresholds for lifestyle behaviour, we derived a weighted composite for Lifestyle Risk. Physiological Load was based on an index using clinical thresholds. Sociodemographics are non-modifiable risk factors and were specified as covariates. We used structural equation modeling to test the model, first using 2014/2015 data from the Indonesian Family Life Survey. Next, we fitted a smaller model with longitudinal data (2007/2008 to 2014/2015), given limited earlier data. Both models showed the indirect effects of Lifestyle Risk on Diabetes Risk via the mediator of Physiological Load, whereas the direct effect was only supported in the cross-sectional analysis. Specifying Lifestyle Risk as an observable, composite variable incorporates the cumulative effect of risk behaviour and differentiates this study from previous studies assessing it as a latent construct. The parsimonious model groups the multifarious risk factors and illustrates modifiable pathways that could be applied in chronic disease prevention efforts.

Physical activity in the management of obesity in adults: A position statement from Exercise and Sport Science Australia

This Position Statement examines the evidence for physical activity in weight and adiposity loss, prevention of weight and adiposity gain, and in weight regain in adults, and provides guidance on implications for exercise practitioners. Research evidence indicates that >150 min but preferably 300 min per week of aerobic activity of at least moderate intensity is required to prevent weight and adiposity gain, and at least the upper end of this range of activity to prevent weight regain after weight loss. For meaningful weight and total adiposity loss, a minimum of 300-420 min per week of aerobic activity of at least moderate intensity is required. The evidence around the volume of aerobic physical activity required to reduce central adiposity is emerging, and research suggests that it may be substantially less than that required for weight loss. The impact of high-intensity physical activity and resistance exercise for weight management is uncertain. During consultations for weight management, exercise practitioners should advise that metabolic and cardiovascular health benefits can be achieved with physical activity at any weight, and irrespective of weight change.

Socioeconomic Inequalities in Physical Activity and Sedentary Behaviour among the Chilean Population: A Systematic Review of Observational Studies

Socioeconomic inequalities in physical (in)activity and sedentary behaviours are key mediators in obesity and health socioeconomic inequalities. Considering the high and uneven obesity rates in Chile, this review aims to systematically assess the socioeconomic inequalities in physical activity (PA) and sedentary behaviour (SB) among the Chilean population from different age groups. Peer-reviewed and grey literature were searched from inception until 31st December 2019 in PubMed, Scopus, PsycINFO, Web of Sciences and LILACS. Publications in English and Spanish, from observational studies that reported the comparison of at least one indicator of PA or SB between at least two groups of different socioeconomic positions (SEP), from the general Chilean population, were included. Data searches, screening, extraction, and quality assessment, using the Newcastle Ottawa Quality Assessment Scale for observational studies, were conducted by two independent researchers. Seventeen articles (from 16 studies) met the inclusion criteria (14 cross-sectional; two cohort). Across these, quality was considered low, medium and high for 19%, 69% and 13%, respectively. Results showed consistent evidence for a lower leisure-time PA and sitting time, and higher physical inactivity among adults from the lower, compared to the highest, SEP groups. Associations between SEP and total PA, moderate-to-vigorous PA, low PA, and transport and work-related PA were inconsistent. These findings provide insights to public health and physical activity researchers and policymakers aiming to reduce socioeconomic inequalities in PA and SB in Chile and other countries.

The impact of COVID-19 lockdown on physical activity and weight gain among active adult population in Israel: a cross-sectional study

BACKGROUND

The COVID-19 outbreak holds public health concerns. The stay-at-home increases sedentary behavior, with unintended adverse outcomes. Since organized recreation and sports facilities were closed, we aimed to study how the crisis of closure affected exercise habits and weight gain among the trainee population in Israel. We examined differences in weight gain among individuals with different PA activities and assessed their ability to adapt to digital media as an alternative training structure.

METHODS

A cross-sectional survey consisted of a multiple-choice questionnaire obtained using a web-based survey application. Trainees (1202) who exercised steadily anonymously answered the questionnaire sent by their coaches regarding their activity and weight gain during lockdown times.

RESULTS

Results confirmed that 70% of Israelis trained less than their usual routine, 60% used digital media for training, 55% gained weight. Half of the respondents gained more than 2 kg, with an average increase of 1.2 kg. However, those who exhibited a higher physical activity level gained less weight. Using digital media for training was associated with higher physical activity levels. The aged population was less likely to use digital media.

CONCLUSIONS

Since increased sedentary behavior could increase the risk for potential worsening of health conditions, health agencies should look for strategies, including digital remote media training to promote physical activity and subsequently, preventing the increased burden of future comorbidities worsening by a sedentary lifestyle. Approval: by the Helsinki ethics committee of Sheba Medical Center (6504-19-SMC).

The association between lunch composition and obesity in Iranian adults

We aimed to assess the dietary composition of lunch meal using a posteriori-derived dietary patterns and to determine the association of lunch composition with obesity in a sample of Iranian adults. This cross-sectional study was conducted on 850 men and women in Tehran (aged 20-59 years). Dietary intakes were assessed using three 24-h dietary recalls, and dietary patterns were identified via principal component factor analysis. For each identified pattern, scores were calculated for each participant and then classified into tertiles. Central obesity was defined WHO criteria. General obesity was defined as a BMI of more than 30 kg/m2. Three major dietary patterns were identified at lunch meal using twelve food groups: 'Bread, grains and fat', 'Western' and 'Potato and eggs'. After adjustment for potential confounders, participants at the top tertile of the 'Bread, grains and fat' dietary pattern had greater odds for a higher waist-to-hip ratio (WHR), compared with those in the lowest tertile (OR: 1·44, 95 % CI 1·01, 2·07). However, we found no association between 'Western' or 'potato and eggs' patterns and WHR (OR: 0·89, 95 % CI 0·62, 1·28 and OR: 1·16, 95 % CI 0·69, 1·42, respectively). None of the identified dietary patterns was associated when defining obesity with waist circumference or BMI. In conclusion, participants had a greater chance of central obesity defined based on WHR following a lunchtime pattern with a higher and positive loading factor for 'Bread, grains and fat'.

Effect of exercise training on weight loss, body composition changes, and weight maintenance in adults with overweight or obesity: An overview of 12 systematic reviews and 149 studies

This overview of reviews aimed to summarize the effects of exercise training programs on weight loss, changes in body composition, and weight maintenance in adults with overweight or obesity. A systematic search of systematic reviews and meta-analyses (SR-MAs) published between 2010 and December 2019 was performed. Only SR-MAs of controlled trials were included. The mean difference (MD) or standardized MD (SMD) were extracted from SR-MAs. Twelve SR-MAs (149 studies) were included. Exercise led to a significant weight loss (4 SR-MAs, MDs ranging from -1.5 to -3.5 kg), fat loss (4 SR-MAs, MDs ranging from -1.3 to -2.6 kg) and visceral fat loss (3 SR-MAs, SMDs ranging from -0.33 to -0.56). No difference in weight, fat, and visceral loss was found between aerobic and high-intensity interval training as long as energy expenditure was equal. Resistance training reduced lean mass loss during weight loss (1 SR-MA, MD: 0.8 [95%CI: 0.4-1.3] kg). No significant effect of exercise was found on weight maintenance (1 SR-MA). These findings show favorable effects of exercise training on weight loss and body composition changes in adults with overweight or obesity. Visceral fat loss may lead to benefits for cardiometabolic health. More research is needed to identify training modalities that promote weight maintenance.

The Relationship of Diet and Physical Activity with Weight Gain and Weight Gain Prevention in Women of Reproductive Age

Reproductive-age women often see increased weight gain, which carries an increased risk of long-term overweight and obesity and adverse maternal and child health outcomes. Supporting women to achieve optimal weight through lifestyle modification (diet and physical activity) is of critical importance to reduce weight gain across key reproductive life-stages (preconception, pregnancy and postpartum). This review comprehensively summarizes the current state of knowledge on the contribution of diet and physical activity to weight gain and weight gain prevention in reproductive-aged women. Suboptimal diets including a higher proportion of discretionary choices or energy intake from fats, added sugars, sweets or processed foods are associated with higher weight gain, whereas increased consumption of core foods including fruits, vegetables and whole grains and engaging in regular physical activity are associated with reduced weight gain in reproductive age women. Diet and physical activity contributing to excessive gestational weight gain are well documented. However, there is limited research assessing diet and physical activity components associated with weight gain during the preconception and postpartum period. This review highlights the need for further research to identify key dietary and physical activity components targeting the critical windows of reproductive life-stages in women to best guide interventions to prevent weight gain.

A High-Protein, Low Glycemic Index Diet Suppresses Hunger but Not Weight Regain After Weight Loss: Results From a Large, 3-Years Randomized Trial (PREVIEW)

Background: Previous studies have shown an increase in hunger during weight-loss maintenance (WLM) after diet-induced weight loss. Whether a combination of a higher protein, lower glycemic index (GI) diet and physical activity (PA) can counteract this change remains unclear. Aim: To compare the long-term effects of two diets [high protein (HP)-low GI vs. moderate protein (MP)-moderate GI] and two PA programs [high intensity (HI) vs. moderate intensity (MI)] on subjective appetite sensations during WLM after ≥8% weight loss (WL). Methods: Data derived from the 3-years PREVIEW randomized intervention study. An 8-weeks WL phase using a low-energy diet was followed by a 148-weeks randomized WLM phase. For the WLM phase, participants were assigned to one of the four groups: HP-MI, HP-HI, MP-MI, and MP-HI. Available data from 2,223 participants with overweight or obesity (68% women; BMI ≥ 25 kg/m²). Appetite sensations including satiety, hunger, desire to eat, and desire to eat something sweet during the two phases (at 0, 8 weeks and 26, 52, 104, and 156 weeks) were assessed based on the recall of feelings during the previous week using visual analogue scales. Differences in changes in appetite sensations from baseline between the groups were determined using linear mixed models with repeated measures. Results: There was no significant diet × PA interaction. From 52 weeks onwards, decreases in hunger were significantly greater in HP-low GI than MP-moderate GI (P _{time × diet} = 0.018, P _dietgroup = 0.021). Although there was no difference in weight regain between the diet groups (P _{time × diet} = 0.630), hunger and satiety ratings correlated with changes in body weight at most timepoints. There were no significant differences in appetite sensations between the two PA groups. Decreases in hunger ratings were greater at 52 and 104 weeks in HP-HI vs. MP-HI, and greater at 104 and 156 weeks in HP-HI vs. MP-MI. Conclusions: This is the first long-term, large-scale randomized intervention to report that a HP-low GI diet was superior in preventing an increase in hunger, but not weight regain, during 3-years WLM compared with a MP-moderate GI diet. Similarly, HP-HI outperformed MP-HI in suppressing hunger. The role of exercise intensity requires further investigation. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT01777893.

Evaluation of a new causal chain model for predicting embedded psychosocial and behavioral relationships in a community-based obesity treatment seeking maintained weight loss

A new causal chain model positing theory- and research-based interrelationships among psychosocial and behavioral variables leading to weight loss and its maintenance was assessed. Two samples of women participating in community-based cognitive-behavioral obesity treatments were assessed over either 6 months (weight loss phase; N = 103), or additionally including Months 6-12 (weight-loss maintenance phase; N = 101). Analyses first evaluated whether baseline physical, demographic, behavioral (physical activity, fruit/vegetable intake), and/or psychosocial (self-regulation, self-efficacy, negative mood) variables significantly predicted weight change. Further analyses assessed whether changes in model-based behavioral and psychosocial variables significantly differed by groupings of participants based on their short-term weight loss and weight-loss maintenance/further loss. The predictive value of changes in the psychosocial variables on behavioral changes was next assessed, also accounting for group. Finally, mediation, moderation, and moderated mediation analyses tested proposed causal chain-based interrelationships among variables. Of the 12 variables assessed at baseline, only weight was inversely associated with lost weight, and only fruit/vegetable intake was positively associated with effects during the weight-loss maintenance phase. Overall improvements in behavioral and psychosocial variables were significantly greater in participant groupings with better weight loss and weight-loss maintenance results. Changes in self-regulation, self-efficacy, and mood significantly predicted the weight-loss behavior changes, unaffected by group. Results from the five mediation, moderation, and moderated mediation analyses supported hypotheses based on the new causal chain model. The field testing indicated adequacy of the new causal chain model and informed architectures of behavioral obesity treatments concerned with long-term reductions in excess weight.

Objectively Measured Physical Activity Is Associated With Body Composition and Metabolic Profiles of Pacific and New Zealand European Women With Different Metabolic Disease Risks

Objective: To assess associations between physical activity (PA), body composition, and biomarkers of metabolic health in Pacific and New Zealand European (NZE) women who are known to have different metabolic disease risks. Methods: Pacific (n = 142) or NZE (n = 162) women aged 18-45 years with a self-reported body mass index (BMI) of either 18.5-25.0 kg⋅m-2 or ≥30.0 kg⋅m-2 were recruited and subsequently stratified as either low (<35%) or high (≥35%) BF%, with approximately half of each group in either category. Seven-day accelerometery was used to assess PA levels. Fasting blood was analysed for biomarkers of metabolic health, and whole body dual-energy X-ray absorptiometry (DXA) was used to estimate body composition. Results: Mean moderate-to-vigorous physical activity (MVPA; min⋅day-1) levels differed between BF% (p < 0.05) and ethnic (p < 0.05) groups: Pacific high- 19.1 (SD 15.2) and low-BF% 26.3 (SD 15.6) and NZE high- 30.5 (SD 19.1) and low-BF% 39.1 (SD 18.4). On average Pacific women in the low-BF% group engaged in significantly less total PA when compared to NZE women in the low-BF% group (133 cpm); no ethnic difference in mean total PA (cpm) between high-BF% groups were observed: Pacific high- 607 (SD 185) and low-BF% 598 (SD 168) and NZE high- 674 (SD 210) and low-BF% 731 (SD 179). Multiple linear regression analysis controlling for age and deprivation showed a significant inverse association between increasing total PA and fasting plasma insulin among Pacific women; every 100 cpm increase in total PA was associated with a 6% lower fasting plasma insulin; no significant association was observed in NZE women. For both Pacific and NZE women, there was an 8% reduction in fasting plasma insulin for every 10-min increase in MVPA (p ≤ 0.05). Conclusion: Increases in total PA and MVPA are associated with lower fasting plasma insulin, thus indicating a reduction in metabolic disease risk. Importantly, compared to NZE, the impact of increased total PA on fasting insulin may be greater in Pacific women. Considering Pacific women are a high metabolic disease risk population, these pre-clinical responses to PA may be important in this population; indicating promotion of PA in Pacific women should remain a priority.

Planned morning aerobic exercise in a fasted state increases energy intake in the preceding 24 h

Purpose

We previously observed increased energy intake (EI) at the meal before planned afternoon exercise, but the proximity of the meal to exercise might have reduced the scale of the pre-exercise anticipatory eating. Therefore, this study examined EI in the 24 h before fasted morning exercise.

Methods

Fourteen males, experienced with gym-based aerobic exercise (age 25 ± 5 years, BMI 23.8 ± 2.5 kg/m²), completed counterbalanced exercise (EX) and resting (REST) trials. On day 1, subjects were told the following morning’s activity (EX/REST), before eating ad-libitum laboratory-based breakfast and lunch meals and a home-based afternoon/evening food pack. The following morning, subjects completed 30-min cycling and 30-min running (EX; 3274 ± 278 kJ) or 60-min supine rest (REST; 311 ± 34 kJ) fasted. Appetite was measured periodically, and EI quantified.

Results

Afternoon/evening EI (EX 7371 ± 2176 kJ; REST 6437 ± 2070 kJ; P = 0.017) and total 24-h EI (EX 14,055 ± 3672 kJ; REST 12,718 ± 3379 kJ; P = 0.011) were greater during EX, with no difference between trials at breakfast (P = 0.761) or lunch (P = 0.071). Relative EI (EI minus energy expended through EX/REST) was lower in EX (EX 10,781 ± 3539 kJ; REST 12,407 ± 3385 kJ; P = 0.004).

Conclusion

This study suggests planned fasted aerobic exercise increases EI during the preceding afternoon/evening, precipitating a ~ 10% increase in EI in the preceding 24-h. However, this increase did not fully compensate for energy expended during exercise; meaning exercise induced an acute negative energy balance.

Obesity and eating behavior from the perspective of twin and genetic research

Obesity has dramatically increased during the last decades and is currently one of the most serious global health problems. We present a hypothesis that obesity is a neuro-behavioral disease having a strong genetic background mediated largely by eating behavior and is sensitive to the macro-environment; we study this hypothesis from the perspective of genetic research. Genetic family and genome-wide-association studies have shown well that body mass index (BMI, kg/m²) is a highly heritable and polygenic trait. New genetic variation of BMI emerges after early childhood. Candidate genes of BMI notably express in brain tissue, supporting that this new variation is related to behavior. Obesogenic environments at both childhood family and societal levels reinforce the genetic susceptibility to obesity. Genetic factors have a clear influence on macro-nutrient intake and appetite-related eating behavior traits. Results on the gene-by-diet interactions in obesity are mixed, but emerging evidence suggests that eating behavior traits partly mediate the effect of genes on BMI. However, more rigorous prospective study designs controlling for measurement bias are still needed.

Device-Based Measures of Sedentary Time and Physical Activity Are Associated With Physical Fitness and Body Fat Content

Introduction/Purpose: Physical activity and sedentary time may associate with physical fitness and body composition. Yet, there exists some observational studies that have investigated the associations of device-based measures of sedentary time and physical activity (PA) with cardiorespiratory fitness (CRF) and body composition but associations with muscular fitness (MF) are less studied.

Methods: Objective sedentary time and physical activity was measured by a hip worn accelerometer from 415 young adult men (age: mean 26, standard deviation 7 years). Cardiorespiratory fitness (VO₂max) (CRF) was determined using a graded cycle ergometer test until exhaustion. Maximal force of lower extremities was measured isometrically and lower body power was assessed using standing long jump (MF). Body composition was determined with bioimpedance method. Single and compositional approach was used in regression analysis.

Results: Mean sedentary time was 707 (standard deviation 133) minutes per day (77 ± 8% of the wear time). Volumes of all PA intensities were positively associated with CRF and associations showed linearly increasing magnitudes with higher intensities in single regression models adjusted for age and smoking (p < 0.001). Similarly, PA intensities were positively associated with lower body MF, however, with weaker associations (p < 0.005). After further adjustment for resistance training, the associations remained significant. The associations of the relative distribution of time within sedentary behavior (SB), light intensity PA (LPA) and moderate-to-vigorous PA (MVPA) behaviors as a whole with using compositional analysis further revealed that within the composition MVPA and SB were positively associated with CRF and MF (p < 0.001), while LPA was not. In addition, within the composition, accumulated PA bouts lasting more than 3 min were consistently associated with CRF and MF, and with all body composition variables (p < 0.001), while sedentary time was associated with body fat percentage (p < 0.001).

Conclusion: Promoting physical activity and reducing sedentary time may have positive influence on physical fitness and body fat content, and thereby may offer positive health effects. Physical activity of higher intensities may offer greater benefits.

A dysfunctional family environment and a high body fat percentage negatively affect telomere length in Mexican boys aged 8-10 years

AIM

The aim of this study was to determine whether a direct relationship existed between absolute telomere length (aTL), obesity and familial functionality in a group of Mexican children.

METHODS

We recruited 134 children (52% boys) aged 8-10 years during regular primary care check-ups in 2016 and evaluated physical activity (PA), feeding practices, anthropometrics, body fat percentage (BF%) and family dysfunction. Optimised quantitative PCR determined aTL from genomic deoxyribonucleic acid isolated from saliva samples.

RESULTS

Boys with a healthy BF% showed a higher aTL than their high BF% counterparts (P < .01). aTL was higher in children who performed PA than their sedentary counterparts (P < .05). Alarmingly, 90% of the children belonged to dysfunctional families and a dysfunctional family was correlated with a higher BF% (r = -.57). Negative correlations between the BF% and aTL (r = -.1765) and the BF% and time dedicated to PA (r = -.031) were observed in boys. On the contrary, we found a positive correlation between the aTL and weekly PA (r = .1938). These correlations were not observed in girls.

CONCLUSION

Telomere shortening was associated with a high BF% in boys, but not girls. Dysfunctional families were also a key factor. School PA programmes should be mandatory.

Self-perception of overweight and obesity: A review of mental and physical health outcomes

The obesity crisis is one of the largest public health challenges of the 21st century. Population‐level adiposity has increased dramatically in recent times, and people not recognizing that they have overweight or obesity is now common. It has been widely assumed that not recognizing oneself as having overweight is detrimental to weight management and long‐term health. Here, diverse research is reviewed that converges on the counterintuitive conclusion that not recognizing oneself as having overweight is actually associated with more favourable physical and mental health outcomes than recognizing oneself as having overweight. Drawing on existing models in social psychology and weight stigma research, an explanatory model of the health effects of self‐perception of overweight is outlined. This model proposes that self‐perception of overweight triggers social rejection concerns and the internalization of weight stigma, which in turn induce psychological distress and negatively impact health‐promoting lifestyle behaviours. How self‐perception of overweight may in part explain progression from overweight to obesity, and the public health implications of self‐perception of overweight and obesity are also discussed.

The Effect of Low-Volume High-Intensity Interval Training on Body Composition and Cardiorespiratory Fitness: A Systematic Review and Meta-Analysis

BACKGROUND

Evidence for the efficacy of low-volume high-intensity interval training (HIIT) for the modulation of body composition is unclear.

OBJECTIVES

We examined the effect of low-volume HIIT versus a non-exercising control and moderate-intensity continuous training (MICT) on body composition and cardiorespiratory fitness in normal weight, overweight and obese adults. We evaluated the impact of low-volume HIIT (HIIT interventions where the total amount of exercise performed during training was ≤ 500 metabolic equivalent minutes per week [MET-min/week]) compared to a non-exercising control and MICT.

METHODS

A database search was conducted in PubMed (MEDLINE), EMBASE, CINAHL, Web of Science, SPORTDiscus and Scopus from the earliest record to June 2019 for studies (randomised controlled trials and non-randomised controlled trials) with exercise training interventions with a minimum 4-week duration. Meta-analyses were conducted for between-group (low-volume HIIT vs. non-exercising control and low-volume HIIT vs. MICT) comparisons for change in total body fat mass (kg), body fat percentage (%), lean body mass (kg) and cardiorespiratory fitness.

RESULTS

From 11,485 relevant records, 47 studies were included. No difference was found between low-volume HIIT and a non-exercising control on total body fat mass (kg) (effect size [ES]: - 0.129, 95% confidence interval [CI] - 0.468 to 0.210; p = 0.455), body fat (%) (ES: - 0.063, 95% CI - 0.383 to 0.257; p = 0.700) and lean body mass (kg) (ES: 0.050, 95% CI - 0.250 to 0.351; p = 0.744), or between low-volume HIIT and MICT on total body fat mass (kg) (ES: - 0.021, 95% CI - 0.272 to 0.231; p = 0.872), body fat (%) (ES: 0.005, 95% CI - 0.294 to 0.304; p = 0.974) and lean body mass (kg) (ES: 0.030, 95% CI - 0.167 to 0.266; p = 0.768). However, low-volume HIIT significantly improved cardiorespiratory fitness compared with a non-exercising control (p < 0.001) and MICT (p = 0.017).

CONCLUSION

These data suggest that low-volume HIIT is inefficient for the modulation of total body fat mass or total body fat percentage in comparison with a non-exercise control and MICT. A novel finding of our meta-analysis was that there appears to be no significant effect of low-volume HIIT on lean body mass when compared with a non-exercising control, and while most studies tended to favour improvement in lean body mass with low-volume HIIT versus MICT, this was not significant. However, despite its lower training volume, low-volume HIIT induces greater improvements in cardiorespiratory fitness than a non-exercising control and MICT in normal weight, overweight and obese adults. Low-volume HIIT, therefore, appears to be a time-efficient treatment for increasing fitness, but not for the improvement of body composition.

Sequential Changes Advancing from Exercise-Induced Psychological Improvements to Controlled Eating and Sustained Weight Loss: A Treatment-Focused Causal Chain Model

INTRODUCTION

Behavioral (nonsurgical/nonpharmacologic) weight loss treatments have been overwhelmingly unsuccessful beyond the short term. Rather than incorporating accepted behavioral change theory, most have inadequately relied on providing exercise and nutrition information. Although adherence is a challenge, exercise has emerged as the most robust predictor of sustained weight reduction. However, exercise might be more associated with long-term weight loss through the relationship of its associated psychological changes with improved nutrition than through direct effects of energy expenditures, which are typically minimal in deconditioned individuals.

OBJECTIVE

To facilitate improved helping methods through a proposed theory-based causal chain model in which supported exercise predicts sustained weight loss through successive changes in exercise-related, then eating-related, self-regulation, self-efficacy, and mood.

RESULTS

Segments of the model predict that 1) exercise and eating behaviors will be sequentially improved through increased self-regulatory skill use and self-efficacy and 2) exercise-induced mood improvements will foster greater self-regulation and reduced emotional eating. Short-term psychosocial changes can be leveraged to carry over to longer-term changes and maintained weight reductions. Suggested interventions emerging from the model and supporting research include using self-regulation to enable a habit of regular moderate exercise, facilitating a transfer of self-regulatory skills from an exercise to eating context, and leveraging mood improvements associated with manageable volumes of exercise to improve eating behaviors.

CONCLUSION

The model presents an evidence-based explanation of the exercise-weight loss association through psychosocial mechanisms. It also informs the development of practical methods to facilitate sustainable reductions in weight and health risks in adults with obesity.

Health Perception According to the Lifestyle of University Students

University students are characterized by having inadequate eating habits, along with an unhealthy lifestyle, which, among other factors, can affect the perception they have of their state of health. The aim of the study was to evaluate the health perception of a group of university students according to lifestyle. A cross-sectional observational study was carried out on 214 university students from different universities and branches of knowledge. Anthropometric data were collected. Three questionnaires were administered: PREDIMED (Mediterranean Diet (MD) adherence), SF-36 (perception of health state) and GPAQ (physical activity (PA)). The differences between variables were analyzed using Student-t or Mann-Whitney U, Kruskal-Wallis and Pearson Chi-Square tests. Statistical significance was reached at p < 0.05. Most students were found to be normal weighted. The subjects presented an moderate MD adherence, this being better in Health Sciences students. 75.7% practiced light PA. The health perception is worse for most of the subscales analyzed than that of the reference population (except physical-function, physical-role, and emotional-role). There is an association between PA and health perception: students with intense PA have less body pain and better physical function; the less active, the less vitality. The more physically active subjects the greater MD adherence. Lifestyle and eating habits of health sciences students are healthier than that of students from other branches of knowledge. The physically active subjects have a better perception of quality of life-related to health and greater MD adherence.

Exploration of Finnish adults' successful weight management over the life course: a qualitative study

Background

Despite the current obesogenic environment creating challenges weight management, some people succeed in maintaining a normal weight. This study explored lifelong weight management from the life course perspective. We aimed to gain an insight into the issues related to the pathways of individuals of normal weight from childhood to adulthood, and how their experiences and social connections influence their weight management.

Methods

We approached the research topic using qualitative methods. Two age groups (30–45; 55–70 years, men and women), forming a total of 39 individuals, participated in theme interviews. Thematic analysis resulted in two main categories, namely (1) adoption of lifestyle and (2) maintenance of lifestyle.

Results

Childhood family played a central role in the formation of lifestyle: food-upbringing created the basis for the interviewees’ current diet, and their lives had always been characterized by an active lifestyle. High perceived self-efficacy was vital in weight management. The interviewees were confident about their routines and trusted their abilities to recognize and handle situations that threatened their lifestyles. They possessed skills for adjusting their lifestyle to altered environments, and showed a high level of coping self-efficacy. The interviewees also highlighted the importance of habits for weight management. They had improved their adopted lifestyle through constant learning. New routines had become more internalized through active repetition, finally turning into habitual practices, which simplified weight management.

Conclusions

Based on our interviews, we conclude that childhood was important in the development of the health-promoting lifestyle of our interviewees. However, weight management was described as a journey over the life course, and success also encouraged skills of identifying risks and adjusting actions to cope with challenging situations.

Effect of 12-Week Interventions Involving Nordic Walking Exercise and a Modified Diet on the Anthropometric Parameters and Blood Lipid Profiles in Overweight and Obese Ex-Coal Miners

BACKGROUND

Overweight and obesity after retirement are likely to be caused by unhealthy eating habits and the energy intake exceeding the energy expenditure.

OBJECTIVES

This study was designed to assess the effects of two 12-week interventions involving, respectively, either regular physical activity or a modified lower-calorie diet on the anthropometric parameters and blood lipid profiles in overweight and obese retired miners with lipid disorders.

DESIGN

The study participants (n = 30, aged 58.7 ± 4.1 years, body height 174.8 ± 7.3 cm, body weight 96.6 ± 13.9 kg) were randomly assigned to 2 intervention groups: the Nordic walking group (NW), which exercised with intensity from 60 to 70% of participants' maximal heart rates for 1 h 3 times a week, and the modified diet group (MD). Modification of the diet consisted of reducing the daily energy intake by 30%, increasing the dietary content of mono- and polyunsaturated fatty acids and dietary fiber, and reducing the proportion of saturated fatty acids. The variables assessed at baseline and after 6 and 12 weeks were: anthropometric parameters (body weight, fat mass content [FM], fat percentage [BF], BMI, waist circumference [WC], hip circumference [HC], and waist-to-hip ratio [WHR]) and blood lipid indicators (total cholesterol [TC], triglycerides [TG], low density lipoprotein cholesterol [LDL-C], and high density lip-oprotein cholesterol [HDL-C]).

RESULTS

The body weight of the participants in the NW was lower at week 12 by an average of 5 kg, BMI by 6%, FB by 19%, FM by 15%, WC by 8%, HC by 6%, and WHR by 3%. In the MD, the respective decreases were 8 kg and 8, 25, 20, 6, 2, and 7%. In the MD, the postintervention concentrations of TC and TG were within the reference range.

CONCLUSION

Both 12-week interventions improved the anthropometric parameters and blood lipid profiles of retired heavy manual workers, with the improvements being more pronounced in the dieting group.

Using the Onitor® Track for weight loss: A mixed methods study among overweight and obese women

Non-communicable disease rates associated with being overweight or obese are rising. Technologies warrant consideration as weight loss interventions. Cloudtag's^® Onitor^® Track, a dual-position wearable plus smartphone application, monitors energy expenditure and provides tailored exercise programmes. This research aimed to undertake an experimental study of 20 overweight and obese women using the technology; explore its feasibility and acceptability through interviews; and investigate its behaviour change techniques. The primary outcome was decreased body weight (kg) at 4 weeks. Secondary outcomes were body mass index (kg/m²) and waist circumference (cm) changes. 15 overweight and obese women took part. Results indicated weight loss (median 2.7 kg, p < 0.05) and waist circumference decrease (median 4 cm, p < 0.05), but attrition was high (60%). Users reported dietary changes but few activity adjustments. They valued feedback. 27 behaviour change techniques were identified. The Onitor^® Track shows potential for weight loss in overweight and obese women, but further work is needed.

Physical Activity Intentions and Behavior Mediate Treatment Response in an Acceptance-Based Weight Loss Intervention

BACKGROUND

Acceptance-based treatment (ABT) for weight loss has shown promise for improving outcomes relative to standard behavioral treatment (SBT). One way in which ABT may improve outcomes is through increasing physical activity (PA) intentions and behavior but little research has examined these as mediators of ABT on weight change.

PURPOSE

This study sought to examine ABT's effects on intentions for PA and several objectively measured PA variables during treatment and analyze PA intentions and behaviors as mediators of ABT's effect on weight loss.

METHODS

Participants (N = 189) with overweight/obesity randomized to 1 year of either ABT or SBT completed ecological momentary assessment of PA intentions, accelerometer-based PA assessment, and had weight measured at baseline, mid-treatment, and end of treatment.

RESULTS

ABT had a significantly higher increase than SBT in PA intention minutes at mid-treatment and end of treatment (p < 0.001), and both groups had nonlinear increases in moderate-to-vigorous physical activity (MVPA) that were not significantly different. Sequential mediation models found that ABT's effect on weight loss was partially mediated by higher PA intention minutes at mid-treatment leading to increased MVPA minutes per week. Increased MVPA minutes were obtained by participants increasing the number of days with MVPA bouts.

CONCLUSIONS

ABT's effect on weight loss throughout treatment resulted, in part, from participants increasing their intentions for PA. Controlling for group, higher PA intentions were associated with more PA obtained through more days with exercise.

Commitment Lotteries Promote Physical Activity Among Overweight Adults-A Cluster Randomized Trial

Background

The World Health Organization has identified physical inactivity as the fourth leading risk factor for global mortality. People often intend to engage in physical activity on a regular basis, but have trouble doing so. To realize their health goals, people can voluntarily accept deadlines with consequences that restrict undesired future behaviors (i.e., commitment devices).

Purpose

We examined if lottery-based deadlines that leverage regret aversion would help overweight individuals in attaining their goal of attending their gym twice per week. At each deadline a lottery winner was drawn from all participants. The winners were only eligible for their prize if they attained their gym-attendance goals. Importantly, nonattending lottery winners were informed about their forgone prize. The promise of this counterfactual feedback was designed to evoke anticipated regret and emphasize the deadlines.

Methods

Six corporate gyms with a total of 163 overweight participants were randomized to one of three arms. We compared (i) weekly short-term lotteries for 13 weeks; (ii) the same short-term lotteries in combination with an additional long-term lottery after 26 weeks; and (iii) a control arm without lotteries.

Results

After 13 weeks, participants in the lottery arms attained their attendance goals more often than participants in the control arm. After 26 weeks, we observe a decline in goal attainment in the short-term lottery arm and the highest goal attainment in the long-term lottery arm.

Conclusions

With novel applications, the current research adds to a growing body of research that demonstrates the effectiveness of commitment devices in closing the gap between health goals and behavior.

Clinical Trial information

This trial is registered in the Dutch Trial Register. Identifier: NTR5559

Neighborhood walkability and 12-year changes in cardio-metabolic risk: the mediating role of physical activity

BACKGROUND

Living in walkable neighborhoods may provide long-term cardio-metabolic health benefits to residents. Little empirical research has examined the behavioral mechanisms in this relationship. In this longitudinal study, we examined the potential mediating role of physical activity (baseline and 12-year change) in the relationships of neighborhood walkability with 12-year changes in cardio-metabolic risk markers.

METHODS

The Australian Diabetes, Obesity and Lifestyle study collected data from adults, initially aged 25+ years, in 1999-2000, 2004-05, and 2011-12. We used 12-year follow-up data from 2023 participants who did not change their address during the study period. Outcomes were 12-year changes in waist circumference, weight, systolic and diastolic blood pressure, fasting and 2-h postload plasma glucose, high-density lipoprotein cholesterol, and triglycerides. A walkability index was calculated, using dwelling density, intersection density, and destination density, within 1 km street-network buffers around participants' homes. Spatial data for calculating these measures were sourced around the second follow-up period. Physical activity was assessed by self-reported time spent in moderate-to-vigorous physical activity (including walking). Multilevel models, adjusting for potential confounders, were used to examine the total and indirect relationships. The joint-significance test was used to assess mediation.

RESULTS

There was evidence for relationships of higher walkability with smaller increases in weight (P = 0.020), systolic blood pressure (P < 0.001), and high-density lipoprotein cholesterol (P = 0.002); and, for relationships of higher walkability with higher baseline physical activity (P = 0.020), which, in turn, related to smaller increases in waist circumference (P = 0.006), weight (P = 0.020), and a greater increase in high-density lipoprotein cholesterol (P = 0.005). There was no evidence for a relationship of a higher walkability with a change in physical activity during the study period (P = 0.590).

CONCLUSIONS

Our mediation analysis has shown that the protective effects of walkable neighborhoods against obesity risk may be in part attributable to higher baseline physical activity levels. However, there was no evidence of mediation by increases in physical activity during the study period. Further research is needed to understand other behavioral pathways between walkability and cardio-metabolic health, and to investigate any effects of changes in walkability.

The association between anthropometric measures and physical performance in black adults of the North West Province, South Africa

OBJECTIVE

This study investigated associations between anthropometric measures and physical performance in black South African adults. It was hypothesized that noninvasive, simple anthropometric measurements, such as calf circumference (CC) and body mass index (BMI), may be useful predictors of physical performance and strength.

METHODS

Black human immunodeficiency virus (HIV) negative men and women (aged 32-93 years) participating in the Prospective Urban and Rural Epidemiology (PURE) study were enrolled at baseline in 2005 = 1428). Men and women's anthropometry, socio-demographics and physical activity (PA) were assessed at baseline, 5- and 10-year follow-up. Physical performance (walk speed, chair stand and handgrip strength [HGS]) were assessed at 10-year follow-up. Linear regression models adjusted for potential confounders were used to evaluate the association between anthropometric measures and physical performance.

RESULTS

The combined overweight and obesity prevalence among both men (P = .02) and women (P < .001) increased significantly over 10 years, with significant increases over time in BMI and CC in the women, whereas PA decreased significantly over time in both men and women (P < .0001). BMI and CC were positively associated with HGS in the men (P = .02, P < .0001) and women (P < .0001), while CC was positively associated with walk speed in men only (P = .006) in the cross-sectional analysis of 2015 measurements.

CONCLUSION

BMI and CC in both men and women were positively associated with HGS, but CC was associated with walk speed in the men only. Our study suggests that CC may be a useful predictor of physical performance in black men and to a limited extent in black women.