Does Habitual Physical Activity Increase the Sensitivity of the Appetite Control System? A Systematic Review.

BACKGROUND: It has been proposed that habitual physical activity improves appetite control; however, the evidence has never been systematically reviewed. OBJECTIVE: To examine whether appetite control (e.g. subjective appetite, appetite-related peptides, food intake) differs according to levels of physical activity. DATA SOURCES: Medline, Embase and SPORTDiscus were searched for articles published between 1996 and 2015, using keywords pertaining to physical activity, appetite, food intake and appetite-related peptides. STUDY SELECTION: Articles were included if they involved healthy non-smoking adults (aged 18-64 years) participating in cross-sectional studies examining appetite control in active and inactive individuals; or before and after exercise training in previously inactive individuals. STUDY APPRAISAL AND SYNTHESIS: Of 77 full-text articles assessed, 28 studies (14 cross-sectional; 14 exercise training) met the inclusion criteria. RESULTS: Appetite sensations and absolute energy intake did not differ consistently across studies. Active individuals had a greater ability to compensate for high-energy preloads through reductions in energy intake, in comparison with inactive controls. When physical activity level was graded across cross-sectional studies (low, medium, high, very high), a significant curvilinear effect on energy intake (z-scores) was observed. LIMITATIONS: Methodological issues existed concerning the small number of studies, lack of objective quantification of food intake, and various definitions used to define active and inactive individuals. CONCLUSION: Habitually active individuals showed improved compensation for the energy density of foods, but no consistent differences in appetite or absolute energy intake, in comparison with inactive individuals. This review supports a J-shaped relationship between physical activity level and energy intake. Further studies are required to confirm these findings. PROSPERO REGISTRATION NUMBER: CRD42015019696

Long-term sustainability of a physical activity and nutrition intervention for rural adults with or at risk of metabolic syndrome.

OBJECTIVE: To determine longer-term (18-month) sustainability of a six-month physical activity and nutrition intervention for 50-69-year-olds with or at risk of metabolic syndrome residing in a rural Australian community. METHODS: Participants (n=151) were followed-up at 12 and 18 months post-intervention. Changes in nutrition behaviours (fat and fibre barometer); physical activity behaviours (IPAQ); anthropometry (waist-hip ratio, weight, BMI), blood pressure, blood parameters (triglycerides, glucose, LDL-, HDL-, non-HDL, total-cholesterol) were analysed using t-tests and repeated measures ANOVA. RESULTS: Across three time points (6, 12 and 18 months) marginal decrease was observed for waist circumference (p=0.001), a modest increase was observed for diastolic blood pressure (p=0.010) and other outcome measures remained stable. CONCLUSION: Maintenance and ongoing improvement of health behaviours in the longer-term is challenging. Future studies must look for ways to embed interventions into communities so they are sustainable and investigate new approaches to reduce the risk of chronic disease. Implications for public health: Metabolic syndrome is a major health issue in Australia and worldwide. Early identification and management are required to prevent the progression to chronic disease. This 18-month follow-up showed that outcomes measures remained relatively stable; however, there is a need to investigate opportunities for embedded community interventions to support long-term health behaviour change

Behavioural Lifestyle Intervention Study (BLIS) in patients with type 2 diabetes in the United Arab Emirates: A randomized controlled trial

BACKGROUND: Lifestyle modification is a cornerstone of the management of type 2 diabetes. However, in the United Arab Emirates, a country where type 2 diabetes is highly prevalent, non-compliance with a healthy lifestyle has been reported in many diabetic Emirati patients. The use of behavioural theories in lifestyle counselling is believed to facilitate behavioural changes, nevertheless, there are no published data regarding the use of structured behavioural lifestyle programmes tailored to suit Emirati culture. The primary objective of this study was to develop a behavioural lifestyle programme and to evaluate its effectiveness in improving glycaemic control in Emirati patients with type 2 diabetes. METHODS: The Behavioural Lifestyle Intervention Study (BLIS) was a translational randomized controlled trial in which patients (n = 35) were randomly assigned to the intervention or control group. Patients in the intervention group went through a six-month behavioural lifestyle programme composed of 8 sessions, whereas patients in the control group received standard care. Cognitive behavioural theory was the underpinning theory for the lifestyle intervention. HbA1c levels were the trial’s primary outcome measure, and the main dietary factor targeted for change was carbohydrate intake. They were measured at baseline, 3 months and 6 months and were assessed using one-way ANOVA at a significance level of P < 0.05. All of the patients were then followed up at 1 year on all outcome measures. RESULTS: At 6 months, the HbA1c levels of the patients (n = 18) in the intervention group were significantly reduced (−1.56 ± 1.81, P < 0.05), whereas no significant change was observed in the patients of the control group. Similarly, both carbohydrate intake from cereals and total carbohydrate intake (in grams) were reduced (p < 0.05) in the intervention group, by 32.92 ± 54.34 and 20.94 ± 56.73, respectively. At 1 year, the patients in the intervention group maintained a significant reduction in HbA1c levels (−1.12 ± 1.46, p < 0.05), whereas no change was observed in the control group. CONCLUSION: The behavioural lifestyle intervention programme was effective in improving glycaemic control and compliance with carbohydrate intake goals in Emirati patients with type 2 diabetes. Larger randomized controlled trials are needed to validate these results and to identify key behavioural strategies that will improve compliance to lifestyle modifications in real life. TRIAL REGISTRATION: Clinicaltrials.gov trial identifier NCT0238693

Associations between weight change and biomarkers of cardiometabolic risk in South Asians:secondary analyses of the PODOSA trial

Background/Objectives: The association of weight changes with cardiometabolic biomarkers in South Asians has been sparsely studied. Subjects/Methods: We measured cardiometabolic biomarkers at baseline and after 3 years in the Prevention of Diabetes and Obesity in South Asians Trial. We investigated the effect of a lifestyle intervention on biomarkers in the randomized groups. In addition, treating the population as a single cohort, we estimated the association between change in weight and change in biomarkers. Results: Complete data were available at baseline and after 3 years in 151 participants. At 3 years, there was an adjusted mean reduction of 1·44 kg (95% confidence interval (95% CI): 0.18–2.71) in weight and 1.59 cm (95% CI: 0.08–3.09) in waist circumference in the intervention arm as compared with the control arm. There was no clear evidence of difference between the intervention and control arms in change of mean value of any biomarker. As a single cohort, every 1 kg weight reduction during follow-up was associated with a reduction in triglycerides (−1.3%, P=0.048), alanine aminotransferase (−2.5%, P=0.032), gamma-glutamyl transferase (−2.2%, P=0.040), leptin (−6.5%, P&lt;0.0001), insulin (−3.7%, P=0.0005), fasting glucose (−0.8%, P=0.0071), 2-h glucose (−2.3%, P=0.0002) and Homeostatic Model Assessment of insulin resistance (HOMA-IR: −4.5%, P=0.0002). There was no evidence of associations with other lipid measures, tissue plasminogen activator, markers of inflammation or blood pressure. Conclusions: We demonstrate that modest weight decrease in SAs is associated with improvements in markers of total and ectopic fat as well as insulin resistance and glycaemia in South Asians at risk of diabetes. Future trials with more intensive weight change are needed to extend these findings