Psychedelics and health behaviour change.

Healthful behaviours such as maintaining a balanced diet, being physically active and refraining from smoking have major impacts on the risk of developing cancer, diabetes, cardiovascular diseases and other serious conditions. The burden of the so-called 'lifestyle diseases'-in personal suffering, premature mortality and public health costs-is considerable. Consequently, interventions designed to promote healthy behaviours are increasingly being studied, e.g., using psychobiological models of behavioural regulation and change. In this article, we explore the notion that psychedelic substances such as psilocybin could be used to assist in promoting positive lifestyle change conducive to good overall health. Psilocybin has a low toxicity, is non-addictive and has been shown to predict favourable changes in patients with depression, anxiety and other conditions marked by rigid behavioural patterns, including substance (mis)use. While it is still early days for modern psychedelic science, research is advancing fast and results are promising. Here we describe psychedelics' proposed mechanisms of action and research findings pertinent to health behaviour change science, hoping to generate discussion and new research hypotheses linking the two areas. Therapeutic models including psychedelic experiences and common behaviour change methods (e.g., Cognitive Behaviour Therapy, Motivational Interviewing) are already being tested for addiction and eating disorders. We believe this research may soon be extended to help promote improved diet, exercise, nature exposure and also mindfulness or stress reduction practices, all of which can contribute to physical and psychological health and well-being.

Socio-demographic factors associated with physical activity and sitting time patterns in adults: An analysis based on the Portuguese Food, Nutrition and Physical Activity Survey.

ABSTRACTPhysical activity (PA) and sedentary behaviours (SB) influence health. Since most people engage in different combinations of both behaviours every day, understanding the socio-demographic characteristics of adults with distinct PA and sitting time (ST) patterns is important to contribute to evidence-based planning of public health strategies. Data from a national survey on diet and activity behaviours (IAN-AF, 2015/16) including 1724 adults (50.5% women, 18-64 years) from a representative sample of Portuguese adults was used in this study. Participants were interviewed face-to-face, and the International Physical Activity Questionnaire (IPAQ) was used. Logistic regression examined the associations between socio-demographic factors each of the four-low/high PA-ST groups. PA low/high categories were defined as in IPAQ, while ST low/high categories were defined according to ST tertiles (≤180 min/day, ≥360 min/day). A 'higher risk' behaviour pattern (low PA/high ST) was present in 37.3% of the adults and was likely associated with a middle household income, and with having 12 or more years of education. The 'lower risk' (high PA/low ST) represented 26.6% of the sample and was likely associated with middle-aged adults and with having a lower educational level. Being male, young and highly educated was related to being physically active and spending large amounts of time in ST. Besides adding to the body of mixed evidence on this theme, the identification of the socio-demographic factors associated with each PA/ST pattern will permit national public health authorities to define policies and tailored actions to promote PA and reduce ST.

The Effects of the Type of Exercise and Physical Activity on Eating Behavior and Body Composition in Overweight and Obese Subjects.

The aim of this study was to examine whether a type of exercise favors better compliance with a prescribed diet, higher eating-related motivation, healthier diet composition or greater changes in body composition in overweight and obese subjects. One hundred and sixty-two (males n = 79), aged 18-50 years, were randomized into four intervention groups during 24 weeks: strength, endurance, combined strength + endurance and guideline-based physical activity; all in combination with a 25-30% caloric restriction diet. A food frequency questionnaire and a "3-day food and drink record" were applied pre- and post-intervention. Diet and exercise-related motivation levels were evaluated with a questionnaire developed for this study. Body composition was assessed by DXA and habitual physical activity was measured by accelerometry. Body weight, body mass index (BMI) and body fat percentage decreased and lean body mass increased after the intervention, without differences by groups. No interactions were observed between intervention groups and time; all showing a decreased in energy intake (p < 0.001). Carbohydrate and protein intakes increased, and fat intake decreased from pre- to post-intervention without significant interactions with intervention groups, BMI category or gender (p < 0.001). Diet-related motivation showed a tendency to increase from pre- to post-intervention (70.0 ± 0.5 vs 71.0 ± 0.6, p = 0.053), without significant interactions with intervention groups, BMI or gender. Regarding motivation for exercise, gender x time interactions were observed (F(1,146) = 7.452, p = 0.007): Women increased their motivation after the intervention (pre: 17.6 ± 0.3, post: 18.2 ± 0.3), while men maintained it. These findings suggest that there are no substantial effects of exercise type on energy intake, macronutrient selection or body composition changes. After a six-month weight loss program, individuals did not reduce their motivation related to diet or exercise, especially women. Individuals who initiate a long-term exercise program do not increase their energy intake in a compensatory fashion, if diet advices are included.

Prevalence and Preferences of Self-Reported Physical Activity and Nonsedentary Behaviors in Portuguese Adults.

BACKGROUND: This study describes levels of self-reported physical activity, frequency of selected opportunistic nonsedentary behaviors, and preferences of leisure-time activities in a representative sample of Portuguese adults, using data from a national survey on diet and activity behaviors (National Food, Nutrition and Physical Activity Survey, IAN-AF, 2015-2016). METHODS: Participants were 3873 Portuguese adults (1827 men). They were interviewed face to face, and the short version of the International Physical Activity Questionnaire was used. Regular leisure-time programmed activities, and 6 additional items, forming the activity choice index questionnaire, were used to assess 6 discrete nonsedentary behaviors. RESULTS: Using the International Physical Activity Questionnaire categories, 42.3% of the sample were classified as low active, 30.6% as moderately active, and 27.1% as highly active. Walking, health/fitness activities, running, group gymnastics classes, swimming/pool activities, football/futsal, and cycling were the most popular leisure-time activities. Between 15% (parking further away from destinations) and 48% (using the stairs instead of elevators) of participants reported that they frequently adopted commonly recommended nonsedentary activities. CONCLUSIONS: This study updates self-reported physical activity prevalence for Portugal adults, including older adults. In addition, it uniquely describes leisure-time activity preferences in the population and also the relative frequency of several nonsedentary activities of daily living.

What is the effect of diet and/or exercise interventions on behavioural compensation in non-exercise physical activity and related energy expenditure of free-living adults? A systematic review.

Non-exercise physical activity (NEPA) and/or non-exercise activity thermogenesis (NEAT) reductions may occur from diet and/or exercise-induced negative energy balance interventions, resulting in less-than-expected weight loss. This systematic review describes the effects of prescribed diet and/or physical activity (PA)/exercise on NEPA and/or NEAT in adults. Studies were identified from PubMed, web-of-knowledge, Embase, SPORTDiscus, ERIC and PsycINFO searches up to 1 March 2017. Eligibility criteria included randomised controlled trials (RCT), randomised trials (RT) and non-randomised trials (NRT); objective measures of PA and energy expenditure; data on NEPA, NEAT and spontaneous PA; ≥10 healthy male/female aged>18 years; and ≥7 d length. The trial is registered at PROSPERO-2017-CRD42017052635. In all, thirty-six articles (RCT-10, RT-9, NRT-17) with a total of seventy intervention arms (diet, exercise, combined diet/exercise), with a total of 1561 participants, were included. Compensation was observed in twenty-six out of seventy intervention arms (fifteen studies out of thirty-six reporting declines in NEAT (eight), NEPA (four) or both (three)) representing 63, 27 and 23 % of diet-only, combined diet/exercise, and exercise-only intervention arms, respectively. Weight loss observed in participants who decreased NEAT was double the weight loss found in those who did not compensate, suggesting that the energy imbalance degree may lead to energy conservation. Although these findings do not support the hypothesis that prescribed diet and/or exercise results in decreased NEAT and NEPA in healthy adults, the underpowered trial design and the lack of state-of-the-art methods may limit these conclusions. Future studies should explore the impact of weight-loss magnitude, energetic restriction degree, exercise dose and participant characteristics on NEAT and/or NEPA.

Lack of interest in physical activity - individual and environmental attributes in adults across Europe: The SPOTLIGHT project.

A considerable proportion of European adults report little or no interest in physical activity. Identifying individual-level and environmental-level characteristics of these individuals can help designing effective interventions and policies to promote physical activity. This cross-sectional study additionally explored associations between level of interest and physical activity, after controlling for other individual and environmental variables. Measures of objective and perceived features of the physical environment of residence, self-reported physical activity and other lifestyle behaviors, barriers towards physical activity, general health, and demographics were obtained from 5205 European adults participating in the 2014 online SPOTLIGHT survey. t-Tests, chi-square tests, and generalized estimating equations with negative binomial log-link function were conducted. Adults not interested in physical activity reported a higher BMI and a lower self-rated health, were less educated, and to a smaller extent female and less frequently employed. They were more prone to have less healthy eating habits, and to perceive more barriers towards physical activity. Only minor differences were observed in environmental attributes: the non-interested were slightly more likely to live in neighborhoods objectively characterized as less aesthetic and containing more destinations, and perceived as less functional, safe, and aesthetic. Even after controlling for other individual and environmental factors, interest in physical activity remained a significant correlate of physical activity, supporting the importance of this association. This study is among the first to describe characteristics of individuals with reduced interest in physical activity, suggesting that (lack of) interest is a robust correlate of physical activity in several personal and environmental conditions.

National Food, Nutrition, and Physical Activity Survey of the Portuguese General Population (2015-2016): Protocol for Design and Development.

BACKGROUND: The assessment of food consumption data using harmonized methodologies at the European level is fundamental to support the development of public policies. Portugal is one of the countries with the most outdated information on individual food consumption. OBJECTIVE: The objective of this study was to describe the design and methodology of the National Food, Nutrition and Physical Activity Survey, 2015-2016, developed to collect national and regional data on dietary habits, physical activity (PA), and nutritional status, in a representative sample of the Portuguese general population (3 months-84 years). METHODS: Participants were selected by multistage sampling, using the National Heath Registry as the sampling frame. Data collection, during 12 months, was harmonized according to European guidelines (EU-MENU, European Food Safety Authority [EFSA]). Computer-assisted personal interviewing (CAPI) was performed on a specific electronic platform synchronized with nutritional composition data and considering the FoodEx2 classification system. Dietary assessment was performed using 24-hour recalls (two nonconsecutive, 8-15 days apart) or food diaries in the case of children aged <10 years, complemented with a food propensity questionnaire; PA data (International Physical Activity Questionnaire [IPAQ], the Activity Choice Index [ACI], and 4-days PA diaries); sociodemographic data, and other health-related data were also collected. RESULTS: A sample of 6553 individuals completed the first interview, and 5811 participants completed two dietary assessments. The participation rate among eligible individuals was 33.38% (6553/19,635), considering the first interview, and 29.60% (5811/19,635) for the participants with two completed interviews (about 40% in children and adolescents and 20% in elderly individuals). Results of the survey will be disseminated in national and international scientific journals during 2018-2019. CONCLUSIONS: The survey will assist policy planning and management of national and European health programs on the improvement of nutritional status and risk assessment related to food hazards, and the enhancement of PA. The infrastructures and data driven from this Survey are a solid basis to the development of a future national surveillance system on diet, PA, and other health behaviors reproducible over time.

Weight control behaviors of highly successful weight loss maintainers: the Portuguese Weight Control Registry.

To describe key behaviors reported by participants in the Portuguese Weight Control Registry and to determine associations between these behaviors and weight loss maintenance. A total of 388 adults participated in this cross-sectional study. Assessments included demographic information, weight history, weight loss and weight maintenance strategies, dietary intake, and physical activity. Participants lost on average 18 kg, which they had maintained for ~28 months. Their average dietary intake was 2199 kcal/day, with 33 % of energy coming from fat. About 78 % of participants engaged in levels of moderate-plus-vigorous physical activity exceeding 150 min/week (51 % above 250 min/week), with men accumulating 82 more minutes than women (p < 0.05). The most frequently reported strategies for both weight loss and maintenance were keeping healthy foods at home, consuming vegetables regularly, and having daily breakfast. Greater weight loss maintenance was associated with higher levels of physical activity, walking, weight self-monitoring, establishing specific goals, and with reduced portion size use, reduced consumption of carbohydrates, and increased consumption of protein, (p < 0.05). Results indicate that weight loss maintenance is possible through the adoption of a nutritionally-balanced diet and regular participation in physical activity, but also suggest that adopting different (and, to a degree, individualized) set of behavioral strategies is key for achieving success.

Motivation and Barriers for Leisure-Time Physical Activity in Socioeconomically Disadvantaged Women.

INTRODUCTION: The aim of this study was to examine cross-sectional and longitudinal associations between motivation and barriers for physical activity, and physical activity behavior in women living in socioeconomic disadvantage. This study also examined whether weight control intentions moderate those associations. METHODS: Data from 1664 women aged 18-46 years was collected at baseline and three-year follow-up as part of the Resilience for Eating and Activity Despite Inequality study. In mail-based surveys, women reported sociodemographic and neighborhood environmental characteristics, intrinsic motivation, goals and perceived family barriers to be active, weight control intentions and leisure-time physical activity (assessed through the IPAQ-L). Linear regression models assessed the association of intrinsic motivation, goals and barriers with physical activity at baseline and follow-up, adjusting for environmental characteristics and also physical activity at baseline (for longitudinal analyses), and the moderating effects of weight control intentions were examined. RESULTS: Intrinsic motivation and, to a lesser extent, appearance and relaxation goals for being physically active were consistently associated with leisure-time physical activity at baseline and follow-up. Perceived family barriers, health, fitness, weight and stress relief goals were associated with leisure-time physical activity only at baseline. Moderated regression analyses revealed that weight control intentions significantly moderated the association between weight goals and leisure-time physical activity at baseline (ß = 0.538, 99% CI = 0.057, 0.990) and between intrinsic motivation and leisure-time physical activity at follow-up (ß = 0.666, 99% CI = 0.188, 1.145). For women actively trying to control their weight, intrinsic motivation was significantly associated with leisure-time physical activity at follow-up (ß = 0.184, 99% CI = 0.097, 0.313). CONCLUSIONS: Results suggest that, especially in women trying to control their weight, intrinsic motivation plays an important role in sustaining physical activity participation over time. Also, weight goals for being physically active seem to play a role regarding short-term physical activity participation in this particular population. Addressing these motivational features may be important when promoting physical activity participation in women living in socioeconomically disadvantaged neighborhoods.

A RE-AIM evaluation of evidence-based multi-level interventions to improve obesity-related behaviours in adults: a systematic review (the SPOTLIGHT project).

BACKGROUND: This systematic literature review describes the potential public health impact of evidence-based multi-level interventions to improve obesity-related behaviours in adults, using the Reach, Efficacy, Adoption, Implementation and Maintenance (RE-AIM) framework. METHODS: Electronic databases (PubMed, Embase, and The Cochrane Library) were searched to identify intervention studies published between January 2000 and October 2013. The following inclusion criteria were used: (1) the study included at least one outcome measure assessing obesity-related behaviours (i.e. diet, physical activity or sedentary behaviour), (2) the study collected data over at least one year and (3) the study's intervention targeted adults, was conducted in a specified geographical area or worksite, and was multi-level (i.e. targeting both individual and environmental level). Evidence of RE-AIM of the selected interventions was assessed. Potential public health impact of an intervention was evaluated if information was provided on at least four of the five RE-AIM dimensions. RESULTS: Thirty-five multi-level interventions met the inclusion criteria. RE-AIM evaluation revealed that the included interventions generally had the potential to: reach a large number of people (on average 58% of the target population was aware of the intervention); achieve the assumed goals (89% found positive outcomes); be broadly adopted (the proportion of intervention deliverers varied from 9% to 92%) and be sustained (sixteen interventions were maintained). The highest potential public health impact was found in multi-level interventions that: 1) focused on all levels at the beginning of the planning process, 2) guided the implementation process using diffusion theory, and 3) used a website to disseminate the intervention. CONCLUSIONS: Although most studies underreported results within the RE-AIM dimensions, the reported Reach, Effectiveness, Adoption, Implementation and Maintenance were positively evaluated. However, more information on external validity and sustainability is needed in order to take informed decisions on the choice of interventions that should be implemented in real-world settings to accomplish long-term changes in obesity-related behaviours.

The association between physical activity and eating self-regulation in overweight and obese women.

OBJECTIVE: Successful weight management relies heavily on eating and exercise behaviors. However, little is known about the association between both on a psychosocial level. This study examined the relationship between exercise and eating regulation by exploring the mediating effects of negative body image investment and depressive mood, and their stability through time. METHODS: Analyses were conducted at two different moments (12 and 36 months), involving a sample of 221 overweight/obese women (age: 37.6 ± 7 years; BMI: 31.6 ± 4.1 kg/m(2)) that participated in a behavioral weight control intervention. Bivariate correlations and mediation analyses using Preacher & Hayes resampling procedures were conducted. RESULTS: At 12 months, negative body image investment was the only significant mediator of the exercise-eating relationship. This variable explained larger portions of the indirect effects of structured rather than lifestyle exercise on eating. At 36 months, negative investment and to a lesser extent depressive mood partially explained the exercise-eating association. CONCLUSIONS: Our findings suggest that, besides physiological effects of exercise, psychological mechanisms related to body image and mood also explain the role of physical activity as a 'gateway behavior' for improved eating regulation in overweight women. These effects appear to be stable and may help understand the key role of exercise in long-term weight management.

Exercise, physical activity, and self-determination theory: a systematic review.

BACKGROUND: Motivation is a critical factor in supporting sustained exercise, which in turn is associated with important health outcomes. Accordingly, research on exercise motivation from the perspective of self-determination theory (SDT) has grown considerably in recent years. Previous reviews have been mostly narrative and theoretical. Aiming at a more comprehensive review of empirical data, this article examines the empirical literature on the relations between key SDT-based constructs and exercise and physical activity behavioral outcomes. METHODS: This systematic review includes 66 empirical studies published up to June 2011, including experimental, cross-sectional, and prospective studies that have measured exercise causality orientations, autonomy/need support and need satisfaction, exercise motives (or goal contents), and exercise self-regulations and motivation. We also studied SDT-based interventions aimed at increasing exercise behavior. In all studies, actual or self-reported exercise/physical activity, including attendance, was analyzed as the dependent variable. Findings are summarized based on quantitative analysis of the evidence. RESULTS: The results show consistent support for a positive relation between more autonomous forms of motivation and exercise, with a trend towards identified regulation predicting initial/short-term adoption more strongly than intrinsic motivation, and intrinsic motivation being more predictive of long-term exercise adherence. The literature is also consistent in that competence satisfaction and more intrinsic motives positively predict exercise participation across a range of samples and settings. Mixed evidence was found concerning the role of other types of motives (e.g., health/fitness and body-related), and also the specific nature and consequences of introjected regulation. The majority of studies have employed descriptive (i.e., non-experimental) designs but similar results are found across cross-sectional, prospective, and experimental designs. CONCLUSION: Overall, the literature provides good evidence for the value of SDT in understanding exercise behavior, demonstrating the importance of autonomous (identified and intrinsic) regulations in fostering physical activity. Nevertheless, there remain some inconsistencies and mixed evidence with regard to the relations between specific SDT constructs and exercise. Particular limitations concerning the different associations explored in the literature are discussed in the context of refining the application of SDT to exercise and physical activity promotion, and integrating these with avenues for future research.

Promoting physical activity: development and testing of self-determination theory-based interventions.

A growing number of studies have pulled from Deci and Ryan's Self-Determination Theory to design interventions targeting health behavior change. More recently, researchers have begun using SDT to promote the adoption and maintenance of an active lifestyle. In this review, we aim to highlight how researchers and practitioners can draw from the SDT framework to develop, implement, and evaluate intervention efforts centered on increasing physical activity levels in different contexts and different populations. In the present paper, the rationale for using SDT to foster physical activity engagement is briefly reviewed before particular attention is given to three recent randomized controlled trials, the Canadian Physical Activity Counseling (PAC) Trial, the Empower trial from the UK, and the Portuguese PESO (Promotion of Health and Exercise in Obesity) trial, each of which focused on promoting physical activity behavior. The SDT-based intervention components, procedures, and participants are highlighted, and the key findings that have emanated from these three trials are presented. Lastly, we outline some of the limitations of the work conducted to date in this area and we acknowledge the challenges that arise when attempting to design, deliver, and test SDT-grounded interventions in the context of physical activity promotion.

Motivation, self-determination, and long-term weight control.

This article explores the topics of motivation and self-regulation in the context of weight management and related behaviors. We focus on the role of a qualitative approach to address motivation--not only considering the level but also type of motivation--in weight control and related behaviors. We critically discuss the operationalization of motivation in current weight control programs, present a complementary approach to understanding motivation based on self-determination theory, and review empirical findings from weight control studies that have used self-determination theory measures and assessed their association with weight outcomes. Weight loss studies which used Motivational Interviewing (MI) are also reviewed, considering MI's focus on enhancing internal motivation. We hypothesize that current weight control interventions may have been less successful with weight maintenance in part due to their relative disregard of qualitative dimensions of motivation, such as level of perceived autonomy, often resulting in a motivational disconnect between weight loss and weight-related behaviors. We suggest that if individuals fully endorse weight loss-related behavioral goals and feel not just competent but also autonomous about reaching them, as suggested by self-determination theory, their efforts are more likely to result in long-lasting behavior change.

The role of lean body mass and physical activity in bone health in children.

In the context of physical education curricula, markers of physical fitness (e.g., aerobic capacity, muscular strength, flexibility, and body mass index or body fat) are usually evaluated in reference to health standards. Despite their possible mediating role in the relationship between weight-bearing or muscle forces and features of bone tissue, these attributes of fitness may not be the most relevant to predict skeletal health. It is therefore important to analyze the relative contribution of these factors to the variability in bone tissue of different parts of the skeleton, and to analyze it by gender, as sensitivity to mechanical loading can diverge for boys and girls. We compared the effects of habitual physical activity (PA) and lean mass, as surrogates of weight-bearing and muscle forces, and of physical fitness (aerobic and muscle capacity of lower and upper limbs) on bone mineral content (BMC) and size of total body, lumbar spine, femoral neck, and 1/3 radius in 53 girls and 64 boys from 7.9 to 9.7 years of age. After controlling for bone age, body mass, body height, and calcium intake, lean mass was the most important predictor of bone size and/or mineral in both genders (p < 0.05), while habitual weight-bearing PA positively influenced BMC in boys (p < 0.05). The effect of muscle in bone was not determined by PA and fitness score did not explain bone variability. Femoral neck was the bone site more closely associated with mechanical loading factors; boys with a PA > 608 counts/min/day (~105 min/day of moderate and vigorous intensity) showed 13-20% more BMC than those with less physical activity, and girls with a lean mass >19 kg showed 12-19% more BMC than those with less lean mass. These findings suggest that lean mass was the most important predictor of bone size and/or mineralization in both genders, while habitual weight-bearing PA appears to positively impact on bone mineral in prepubertal boys and that both lean mass and PA need to be considered in physical education curricula and other health-enhancing programs.

How many steps/day are enough? For adults.

Physical activity guidelines from around the world are typically expressed in terms of frequency, duration, and intensity parameters. Objective monitoring using pedometers and accelerometers offers a new opportunity to measure and communicate physical activity in terms of steps/day. Various step-based versions or translations of physical activity guidelines are emerging, reflecting public interest in such guidance. However, there appears to be a wide discrepancy in the exact values that are being communicated. It makes sense that step-based recommendations should be harmonious with existing evidence-based public health guidelines that recognize that "some physical activity is better than none" while maintaining a focus on time spent in moderate-to-vigorous physical activity (MVPA). Thus, the purpose of this review was to update our existing knowledge of "How many steps/day are enough?", and to inform step-based recommendations consistent with current physical activity guidelines. Normative data indicate that healthy adults typically take between 4,000 and 18,000 steps/day, and that 10,000 steps/day is reasonable for this population, although there are notable "low active populations." Interventions demonstrate incremental increases on the order of 2,000-2,500 steps/day. The results of seven different controlled studies demonstrate that there is a strong relationship between cadence and intensity. Further, despite some inter-individual variation, 100 steps/minute represents a reasonable floor value indicative of moderate intensity walking. Multiplying this cadence by 30 minutes (i.e., typical of a daily recommendation) produces a minimum of 3,000 steps that is best used as a heuristic (i.e., guiding) value, but these steps must be taken over and above habitual activity levels to be a true expression of free-living steps/day that also includes recommendations for minimal amounts of time in MVPA. Computed steps/day translations of time in MVPA that also include estimates of habitual activity levels equate to 7,100 to 11,000 steps/day. A direct estimate of minimal amounts of MVPA accumulated in the course of objectively monitored free-living behaviour is 7,000-8,000 steps/day. A scale that spans a wide range of incremental increases in steps/day and is congruent with public health recognition that "some physical activity is better than none," yet still incorporates step-based translations of recommended amounts of time in MVPA may be useful in research and practice. The full range of users (researchers to practitioners to the general public) of objective monitoring instruments that provide step-based outputs require good reference data and evidence-based recommendations to be able to design effective health messages congruent with public health physical activity guidelines, guide behaviour change, and ultimately measure, track, and interpret steps/day.

The effect of physical activity on weight loss is mediated by eating self-regulation.

OBJECTIVE: This study tested whether different forms of physical activity (PA) were associated with eating self-regulation during weight control, and if changes in eating behavior mediated the relationship between PA and weight loss, in overweight/obese women. METHODS: 239 women (37.6+/-7.0 years; 31.3+/-4.1kg/m(2)) participated. The intervention group received a 12-month group behavioral treatment designed to increase autonomy and self-regulation for weight control. Controls received a health education program. Assessments included body weight, structured and lifestyle exercise/PA, and eating self-regulation. RESULTS: Moderate+vigorous and lifestyle PA were associated with 12-month change in most eating variables (p<0.05) and with body weight change (p<0.01). Mediation analysis showed that flexible cognitive restraint and emotional eating fully mediated the relation between lifestyle PA and weight change (effect ratio: 0.63). About 34% of the effect of moderate+vigorous PA on weight change was explained by these same mediators (partial mediation). CONCLUSION: Exercise and PA may positively influence weight control through eating self-regulation. Flexible dietary control and reduced emotional overeating are mechanisms by which an active lifestyle can contribute to long-term weight management. PRACTICE IMPLICATIONS: Regular exercise and PA can contribute to improved eating behaviors during weight management. This could represent an important incentive for people seeking weight control.

Environmental and psychosocial correlates of physical activity in Portuguese and Belgian adults.

OBJECTIVES: To investigate differences in reported physical activity levels and in perceived environmental and psychosocial correlates of activity between Portuguese and Belgian adults; and to analyse the relative contribution of environmental and psychosocial variables in explaining physical activity within different contexts in Portugal and Belgium. DESIGN: Cross-sectional study. SETTING: One city in Portugal (Oeiras) and one in Belgium (Ghent). SUBJECTS: In total 526 participants, 247 from Portugal and 279 from Belgium, completed the long International Physical Activity Questionnaire and a validated questionnaire on environmental and psychosocial correlates. RESULTS: For the sum of all activities of at least moderate intensity, a significantly higher mean level of activity was found in Belgian adults (P < 0.001). However, comparable percentages of the Belgian (38%) and Portuguese (42%) samples did not meet the recommendation of 30 min per day. The variance explained by environmental factors was lower (1% to 8%) than by psychosocial factors (maximum 42%). Regression analyses showed activity-specific relations with environmental variables which were analogous in both countries. Walking/cycling for transportation and walking for recreation were related to social support from family and/or friends and to walkability and walking facilities in the neighbourhood. Recreational physical activity was mainly determined by social support, self-efficacy, and perceived benefits and barriers. CONCLUSIONS: Activity campaigns addressing psychosocial determinants are needed to encourage leisure-time activity, while a combination of neighbourhood design changes and encouragement of social support in walking is warranted to increase walking in different contexts.