Exercise in a behavioural weight control programme for obese patients with Type 2 (non-insulin-dependent) diabetes

Effects of combined aerobic exercise and diet on cardiometabolic health in patients with obesity and type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

Lifestyle modifications involving diet and exercise are recommended for patients diagnosed with obesity and type 2 diabetes mellitus (T2DM). The purpose of this review was to systematically evaluate the effects of combined aerobic exercise and diet (AEDT) on various cardiometabolic health-related indicators among individuals with obesity and T2DM.

METHODOLOGY

A comprehensive search of the PubMed/Medline, Web of Science, Scopus, Science Direct, Cochrane, and Google Scholar databases was conducted for this meta-analysis. The Cochrane risk of bias tool was used to evaluate eligible studies, and the GRADE tool was used to rate the certainty of evidence. A random-effects model for continuous variables was used, and the results were presented as mean differences or standardised mean differences with 95% confidence intervals.

RESULTS

A total of 16,129 studies were retrieved; 20 studies were included, and data were extracted from 1,192 participants. The findings revealed significant improvements in body mass index, body weight, waist circumference, systolic blood pressure, diastolic blood pressure, total cholesterol, triglycerides, fasting blood glucose, fasting plasma insulin, glycated hemoglobin, leptin, interleukin-6, C-reactive protein, and adiponectin (p < 0.05) compared to the standard treatment (ST) group. No significant differences were observed between the AEDT and ST groups in fat mass, hip circumference, waist-to-hip ratio, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and tumor necrosis factor-alpha. The present findings are based on low- to moderate-quality evidence.

CONCLUSIONS

AEDT may be a critical behavior for holistic cardiometabolic health-related benefits as a contemporary anti-obesity medication due to its significant positive impact on patients with obesity and T2DM. Nevertheless, further robust evidence is necessary to determine whether AEDT is an effective intervention for lowering cardiovascular and metabolic risk factors among individuals with obesity and T2DM.

Intervention Effects of Physical Activity on Type 2 Diabetic Patients Potentially Infected with COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has clearly had a great influence on the lifestyles of the population, especially on patients with type 2 diabetes mellitus. During the COVID-19 outbreak, many countries/regions implemented social-isolation measures, leading to an increase in negative behaviors and impairing the capability of diabetic patients to resist COVID-19, ultimately causing severe prognoses. Moreover, as the epidemic progressed, multiple studies emphasized the significance of physical exercise in the management of type 2 diabetic patients infected with COVID-19. In this study, we selected research from 1 December 2019 to 9 August 2023 that focused on COVID-19-infected diabetic patients to investigate the impact of type 2 diabetes on the immune functions, inflammation factor levels, lung injuries, and mental disorders of such patients, as well as to assess the risk of novel coronavirus pneumonia in these patients. Additionally, the effects of high-intensity, moderate-intensity, and low-intensity exercises on novel coronavirus pneumonia infection in type 2 diabetic patients and the mechanisms of the effects of such exercise were considered. We concluded that elderly diabetic patients with COVID-19 should perform low-intensity exercises to facilitate their recoveries. This study offers guidance for a proper understanding of the dangers of diabetes and the use of appropriate measures to reduce the risk of novel coronavirus pneumonia infections in type 2 diabetic patients.

Long-Term Effect of Weight Regain Following Behavioral Weight Management Programs on Cardiometabolic Disease Incidence and Risk: Systematic Review and Meta-Analysis

BACKGROUND

Behavioral weight management programs (BWMPs) enhance weight loss in the short term, but longer term cardiometabolic effects are uncertain as weight is commonly regained. We assessed the impact of weight regain after BWMPs on cardiovascular risk factors, diabetes, and cardiovascular disease.

METHODS

Trial registries, 11 databases, and forward-citation searching (latest search, December 19) were used to identify articles published in English, from any geographical region. Randomized trials of BWMPs in adults with overweight/obesity reporting cardiometabolic outcomes at ≥12 months at and after program end were included. Differences between more intensive interventions and comparator groups were synthesized using mixed-effects, meta-regression, and time-to-event models to assess the impact of weight regain on cardiovascular disease incidence and risk.

RESULTS

One hundred twenty-four trials reporting on ≥1 cardiometabolic outcomes with a median follow-up of 28 (range, 11-360) months after program end were included. Median baseline participant body mass index was 33 kg/m2; median age was 51 years. Eight and 15 study arms (7889 and 4202 participants, respectively) examined the incidence of cardiovascular disease and type 2 diabetes, respectively, with imprecise evidence of a lower incidence for at least 5 years. Weight regain in BWMPs relative to comparators reduced these differences. One and 5 years after program end, total cholesterol/HDL (high-density lipoprotein) ratio was 1.5 points lower at both times (82 studies; 19 003 participants), systolic blood pressure was 1.5 mm mercury and 0.4 mm lower (84 studies; 30 836 participants), and HbA1c (%) 0.38 lower at both times (94 studies; 28 083 participants). Of the included studies, 22% were judged at high risk of bias; removing these did not meaningfully change results.

CONCLUSIONS

Despite weight regain, BWMPs reduce cardiometabolic risk factors with effects lasting at least 5 years after program end and dwindling with weight regain. Evidence that they reduce the incidence of cardiovascular disease or diabetes is less certain. Few studies followed participants for ≥5 years.

REGISTRATION

URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42018105744.

TRPV1 (Transient Receptor Potential Vanilloid 1) Sensitization of Skeletal Muscle Afferents in Type 2 Diabetic Rats With Hyperglycemia

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Exercise as a complementary medicine intervention in type 2 diabetes mellitus: A systematic review with narrative and qualitative synthesis of evidence

BACKGROUND AND AIMS

Type 2 diabetes mellitus (T2DM) is a rapidly growing public health issue. This systematic review aimed to narrate and qualitatively synthesize evidence and recommendations of physical activity/exercise for patients with T2DM.

METHODS

The databases Medline through Pubmed, Cochrane, and Scopus were systematically searched from inception to February 08, 2020 using MeSH terms related to "diabetes mellitus" and "physical activity/exercise". Studies were included if they reported on the roles of physical activity/exercise in managing patients with T2DM or effects of physical activity/exercise on glycemic control. Documents identified through the search were analyzed and evidence and recommendations were synthesized qualitatively.

RESULTS

Data were extracted from 16 original articles and 11 systematic reviews with meta-analyses. A qualitative summary of evidence included general items (n = 6) and recommendations for physical activity/exercise (n = 12). Physical activity/exercise can reduce incidence of T2DM, hyperinsulinemia, fasting plasma/blood glucose, HbA1c, body fats, cholesterol, blood pressure, heart rate, cardiovascular risk, and dosage of antidiabetic medications. Physical activity/exercise can improve sensitivity to insulin, muscle strength, oxygen consumption, aerobic capacity, and mental health of patients with T2DM.

CONCLUSION

Despite the increasing interest in incorporating physical activity/exercise in the management of T2DM and improving healthcare delivery, there are still limited clear instructions and guidelines for both the patient and the healthcare provider.

Effects of a Lifestyle-Modification Program on Blood-Glucose Regulation and Health Promotion in Diabetic Patients: A Randomized Controlled Trial

Background

We aimed to investigate the efficacy of the lifestyle intervention (LSI) program in controlling blood glucose regulation and health promotion in type 2 diabetic (T2D) patients.

Methods

Thirty adults with a diagnosed with diabetes were randomly assigned to LSI and control groups. The LSI group maintained their daily routines after participating twice in the LSI program, while control group maintained 4 weeks of daily life without participating in an intervention.

Results

HbA1c levels in the LSI group decreased significantly after participation (p = 0.025) compared with levels before the study, but there was no significant difference between the groups. The weight and body mass index (BMI) of the LSI group tended to decrease significantly compared with the control group (p = 0.054 and p = 0.055, respectively), and the waist circumference (WC) of the LSI group decreased significantly compared with that of the control group (p = 0.048). In the effects of the LSI program according to the polymorphism of GCKR genes, changes in glycated albumin (GA) (%), HbA1c, WC, BMI, and weight showed a significant decrease in the non-risk (TT genotype) GCKR group compared with the risk group (CC and TC genotype).

Conclusion

Application of the four-week LSI program to diabetics revealed positive effects on blood-glucose control and improvement in obesity indicators. In particular, the risk group with variations in the GCKR gene was associated with more genetic effects on indicators such as blood glucose and obesity than was the non-risk group.

Prevalence of Major Behavioral Risk Factors for Type 2 Diabetes

OBJECTIVE

We examined the proportion of American adults without type 2 diabetes that engages in lifestyle behaviors known to reduce type 2 diabetes risk.

RESEARCH DESIGN AND METHODS

We conducted a cross-sectional analysis of 3,679 nonpregnant, nonlactating individuals aged ≥20 years without diabetes (self-reported diagnosis or glycated hemoglobin ≥6.5% [8 mmol/mol] or fasting plasma glucose ≥126 mg/dL) and who provided 2 days of reliable dietary data in the 2007-2012 National Health and Nutrition Examination Surveys (NHANES). We used the average of 2 days of dietary recall and self-reported leisure-time physical activity to assess whether participants met type 2 diabetes risk reduction goals (meeting four or more MyPlate recommendations [adequate consumption of fruits, vegetables, dairy, grains, meat, beans, and eggs]; not exceeding three maximum allowances for alcoholic beverages, added sugars, fat, and cholesterol; and meeting physical activity recommendations [≥150 min/week]).

RESULTS

Approximately 21%, 29%, and 13% of individuals met fruit, vegetable, and dairy goals, respectively. Half (51.6%) met the goal for total grains, compared with 18% for whole grains, and 54.2% met the meat/beans goal and 40.6% met the oils goal. About one-third (37.8%) met the physical activity goal, and 58.6% met the weight loss/maintenance goal. Overall, 3.1% (95% CI 2.4-4.0) of individuals met the majority of type 2 diabetes risk reduction goals. Younger age and lower educational attainment were associated with lower probability of meeting goals.

CONCLUSIONS

A small proportion of U.S. adults engages in risk reduction behaviors. Research and interventions targeted at young and less-educated segments of the population may help close gaps in risk reduction behaviors.

Obesity and metabolic syndrome in COPD: Is exercise the answer?

Approximately half of all patients with chronic obstructive pulmonary disease (COPD) attending pulmonary rehabilitation (PR) programmes are overweight or obese which negatively impacts upon dyspnoea and exercise tolerance particularly when walking. Within the obese population (without COPD), the observed heterogeneity in prognosis is in part explained by the variability in the risk of developing cardiovascular disease or diabetes (cardiometabolic risk) leading to the description of metabolic syndrome. In obesity alone, high-intensity aerobic training can support healthy weight loss and improve the constituent components of metabolic syndrome. Those with COPD, obesity and/or metabolic syndrome undergoing PR appear to do as well in traditional outcomes as their normal-weight metabolically healthy peers in terms of improvement of symptoms, health-related quality of life and exercise performance, and should therefore not be excluded. To broaden the benefit of PR, for this complex population, we should learn from the extensive literature examining the effects of exercise in obesity and metabolic syndrome discussed in this review and optimize the exercise strategy to improve these co-morbid conditions. Standard PR outcomes could be expanded to include cardiometabolic risk reduction to lower future morbidity and mortality; to this end exercise may well be the answer.

The Science of Obesity Management: An Endocrine Society Scientific Statement

The prevalence of obesity, measured by body mass index, has risen to unacceptable levels in both men and women in the United States and worldwide with resultant hazardous health implications. Genetic, environmental, and behavioral factors influence the development of obesity, and both the general public and health professionals stigmatize those who suffer from the disease. Obesity is associated with and contributes to a shortened life span, type 2 diabetes mellitus, cardiovascular disease, some cancers, kidney disease, obstructive sleep apnea, gout, osteoarthritis, and hepatobiliary disease, among others. Weight loss reduces all of these diseases in a dose-related manner-the more weight lost, the better the outcome. The phenotype of "medically healthy obesity" appears to be a transient state that progresses over time to an unhealthy phenotype, especially in children and adolescents. Weight loss is best achieved by reducing energy intake and increasing energy expenditure. Programs that are effective for weight loss include peer-reviewed and approved lifestyle modification programs, diets, commercial weight-loss programs, exercise programs, medications, and surgery. Over-the-counter herbal preparations that some patients use to treat obesity have limited, if any, data documenting their efficacy or safety, and there are few regulatory requirements. Weight regain is expected in all patients, especially when treatment is discontinued. When making treatment decisions, clinicians should consider body fat distribution and individual health risks in addition to body mass index.

Metabolomics studies on db/db diabetic mice in skeletal muscle reveal effective clearance of overloaded intermediates by exercise

Type 2 diabetes mellitus (T2DM) is characterized by hyperinsulinemia, hyperglycemia and insulin resistance, which correlated with high mortality worldwide. Exercise is one of the effective lifestyle interventions in maintaining blood glucose level in the normal range and lowering risk factors. Metabolomics approaches are powerful tools in systematic study of overall metabolic changes in response to disease or interventions. In this study, mass spectrometry-based metabolomics studies were performed to investigate the regulatory effect of moderate intensity of exercise on db/db diabetic mice in skeletal muscle. Both liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) have been carried out to monitor a wide range of regulated metabolites. Ninety-five metabolites were identified which contributing to the discrimination of db/m  + control and db/db diabetic mice. The regulatory effects of exercise on these metabolites were mainly focusing on attenuating the levels of long-chain fatty acids (C14 to C18) and medium-to long-chain acylcarnitines (C12 to C18), indicated that exercise might play a positive role in inhibiting the accumulation of excessive lipids, which is positively related to insulin resistance. In addition, uric acid, which is a risk factor for inflammation, cardiovascular complications, and fatty liver in diabetic patients, together with its intermediates (such as inosinic acid, hypoxanthine, etc.) in purine metabolism pathway, were also substantially down regulated after exercise, indicating exercise might also be protective against hyperuricemia related risks in T2DM. These findings reveal that moderate intensity of exercise might play a positive role in improving the efficiency of lipid metabolism in skeletal muscle and meanwhile enhancing uric acid clearance to prevent lipid accumulation, which might contribute to improved body fitness and body muscle composition.

Exercise as medicine - evidence for prescribing exercise as therapy in 26 different chronic diseases

This review provides the reader with the up-to-date evidence-based basis for prescribing exercise as medicine in the treatment of 26 different diseases: psychiatric diseases (depression, anxiety, stress, schizophrenia); neurological diseases (dementia, Parkinson's disease, multiple sclerosis); metabolic diseases (obesity, hyperlipidemia, metabolic syndrome, polycystic ovarian syndrome, type 2 diabetes, type 1 diabetes); cardiovascular diseases (hypertension, coronary heart disease, heart failure, cerebral apoplexy, and claudication intermittent); pulmonary diseases (chronic obstructive pulmonary disease, asthma, cystic fibrosis); musculo-skeletal disorders (osteoarthritis, osteoporosis, back pain, rheumatoid arthritis); and cancer. The effect of exercise therapy on disease pathogenesis and symptoms are given and the possible mechanisms of action are discussed. We have interpreted the scientific literature and for each disease, we provide the reader with our best advice regarding the optimal type and dose for prescription of exercise.

The Effect of Regular Exercise on Insulin Sensitivity in Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

The purpose of this study was to examine the effect of regular exercise training on insulin sensitivity in adults with type 2 diabetes mellitus (T2DM) using the pooled data available from randomised controlled trials. In addition, we sought to determine whether short-term periods of physical inactivity diminish the exercise-induced improvement in insulin sensitivity. Eligible trials included exercise interventions that involved ≥3 exercise sessions, and reported a dynamic measurement of insulin sensitivity. There was a significant pooled effect size (ES) for the effect of exercise on insulin sensitivity (ES, -0.588; 95% confidence interval [CI], -0.816 to -0.359; P<0.001). Of the 14 studies included for meta-analyses, nine studies reported the time of data collection from the last exercise bout. There was a significant improvement in insulin sensitivity in favour of exercise versus control between 48 and 72 hours after exercise (ES, -0.702; 95% CI, -1.392 to -0.012; P=0.046); and this persisted when insulin sensitivity was measured more than 72 hours after the last exercise session (ES, -0.890; 95% CI, -1.675 to -0.105; P=0.026). Regular exercise has a significant benefit on insulin sensitivity in adults with T2DM and this may persist beyond 72 hours after the last exercise session.

Self-care behaviors of adults with type 2 diabetes mellitus in Greece

The purpose of this study was to examine self-care behaviors of adults with type 2 diabetes mellitus living in the Metropolitan Area of Thessaloniki in Northern Greece. The Summary of Diabetes Self-Care behaviors measurement was administered to 215 patients, out of which 177 were eligible to participate (87 males). Patients, aged 30 years or more, were recruited through a university hospital day-clinic. Older patients (>65 years), as well as those with "higher educational level" did not distribute their daily carbohydrate intake equally. Nevertheless, they were more likely to adapt to their physician's recommendations regarding medication and to regularly perform suggested blood glucose checking. Exercise patterns were more often found for higher educated, earlier diagnosed males. Younger patients were less likely to follow their healthcare professional's recommendations, regarding diet, medication intake, blood glucose checking, foot care and exercise compared to older patients. These results pose a higher risk for complications and morbidity in younger patients with type 2 diabetes mellitus, who most possibly will require intensive treatment in the future.

Association between physical activity advice only or structured exercise training with blood pressure levels in patients with type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

Diabetes is associated with marked cardiovascular morbidity and mortality. However, the association between different types of exercise training and blood pressure (BP) changes is not fully clear in type 2 diabetes.

OBJECTIVE

The aim of this systematic review and meta-analysis of randomized controlled clinical trials (RCTs) was to determine the effects of structured exercise training (aerobic [AER], resistance [RES], or combined [COMB]) and physical activity (PA) advice only on BP changes in patients with type 2 diabetes.

METHODS

Searches in five electronic databases were conducted to retrieve studies published from 1980 to 2013. Eligible studies were RCTs consisting of structured exercise training or PA advice versus no intervention in patients with type 2 diabetes. We used random effect models to derive weighted mean differences (WMDs) of exercises on absolute changes in systolic BP (SBP) and diastolic BP (DBP).

RESULTS

A total of 30 RCTs of structured training (2,217 patients) and 21 of PA advice (7,323 patients) were included. Data were extracted independently in duplicate. Structured exercise was associated with reductions in SBP (WMD -4.22 mmHg; 95% confidence interval [CI] -5.89 to -2.56) and DBP (WMD -2.07 mmHg; 95% CI -3.03 to -1.11) versus controls. In structured exercise interventions, AER and RES were associated with declines in BP, and COMB was not associated with BP changes. However, in sensitivity analysis, a high-intensity protocol within COMB was associated with declines in SBP (WMD -3.30 mmHg; 95% CI -4.71 to -1.89). Structured exercise longer than 150 min/week was associated with greater BP reductions. PA advice only was associated with reduction in SBP (WMD -2.97 mmHg; 95% CI -4.52 to -1.43) and DBP (WMD -1.41 mmHg; 95% CI -1.94 to -0.88) versus controls.

CONCLUSIONS

AER, RES, and high-intensity combined training are associated with BP reduction in patients with type 2 diabetes, especially in exercise programs lasting more than 150 min/week. PA advice only is also associated with lower BP levels.

[Evaluation of a supervised physical exercise program in sedentary patients over 65 years with type 2 diabetes mellitus]

OBJECTIVE

To analyze whether an exercise program can modify glycated hemoglobin (HbA1c), blood pressure (BP), body mass index (BMI), lipids, cardiovascular risk profile (CVR), self-perceived health status (SHS), and pharmaceutical expenditure (PE).

DESIGN

A randomized, single blind, controlled trial.

INTERVENTION

program of supervised aerobic physical exercise. Analysis by intention to treat.

LOCATION

Primary Care: 2 rural health areas. Health Area of Navalmoral. Cáceres. Extremadura. Spain.

PARTICIPANTS

100 type 2 diabetic patients, aged 65 to 80 years, sedentary. Distribution: 50% control group (CG) and 50% intervention group (IG). Abandoned 12%.

INTERVENTION

monitored aerobic exercise: 40minutes, 2 days/week, 3 months.

KEY MEASURES

HbA1c, BP, BMI, lipid, CVR, SHS, PE. Complications during exercise.

RESULTS

There were post-intervention differences between groups in HbA1c, BP, BMI, cholesterol and SHS. In the IG, there was a significant decrease in; HbA1c: 0.2±0.4% (95% CI: 0.1 to 0.3), systolic BP: 11.8±8.5mmHg (95% CI: 5.1 to 11.9), BMI: 0.5±1 (95% CI: 0.2 to 0.8), total cholesterol: 14±28.2mg/dl (95% CI: 5.9 to 22.2), LDL: 18.3±28.2mg/dl 95% CI: 10.2 to 26.3), CVR: 6.7±7.7% (95% CI: 4.5 to 8.9), PE: 3.9±10.2 € (95% CI: 0.9 to 6.8), and an increase in SHS; 4.7±5.7 (95% CI: 3 to 6.3).

CONCLUSIONS

In diabetics over 65 years, a program of monitored aerobic exercise, of easy implementation, improves HbA1c, BP, cholesterol, CVR, PE, and SHS.

Impact of long-term lifestyle programmes on weight loss and cardiovascular risk factors in overweight/obese participants: a systematic review and network meta-analysis

BACKGROUND

The aim of this meta-analysis was to compare the long-term efficacy of diet plus exercise (D+E) vs. diet (D), D+E vs. exercise (E) and D vs. E on anthropometric outcomes and cardiovascular risk factors in overweight and obese participants.

METHODS

Electronic searches were performed in MEDLINE and the Cochrane Central Register of controlled trials. Inclusion criteria were as follows: body mass index≥25 kg/m2 and a minimum intervention period including follow-up of ≥12 months. Outcomes of interest were as follows: anthropometric parameters, blood lipids, blood pressure and cardiorespiratory fitness. Pooled effects were calculated using pairwise random effects and Bayesian random effects network meta-analysis. Results of the corresponding fixed effects models were compared in sensitivity analyses.

RESULTS

Overall, 22 trials (24 reports) met the inclusion criteria and 21 (including 3,521 participants) of them were included in the quantitative analysis. As compared with D, D+E resulted in a significantly more pronounced reduction in body weight [mean differences (MD): -1.38 kg, 95% confidence interval (CI) -1.98 to -0.79], and fat mass (MD: -1.65 kg, 95% CI -2.81 to -0.49], respectively. When comparing D+E with E, MD in change of body weight (-4.13 kg, 95% CI -5.62 to -2.64), waist circumference (-3.00 cm, 95% CI -5.81 to -0.20), and fat mass (-3.60 kg, 95% CI -6.15 to -1.05) was in favour of combined diet and exercise, respectively. Comparing E vs. D, diet resulted in a significantly more pronounced decrease in body weight (MD: -2.93 kg, 95% CI -4.18 to -1.68), and fat mass (MD: -2.20 kg, 95% CI -3.75 to -0.66). D+E yielded also the greatest reductions with respect to blood lipids and blood pressure when compared to single applications of D and E, respectively. Results from the network meta-analyses confirmed these findings.

CONCLUSIONS

Moderate-quality evidence from the present network meta-analysis suggests that D+E can be highly recommended for long-term obesity management. Furthermore, the evidence suggests a moderate superiority of D over E with respect to anthropometric outcomes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42013003906.

Weight gain after orthotopic liver transplantation: is nonalcoholic fatty liver disease cirrhosis a risk factor for greater weight gain?

Posttransplant weight gain is common after orthotopic liver transplantation. We sought to determine the extent of weight gain at 5 years after transplantation in patients with nonalcoholic fatty liver disease (NAFLD) cirrhosis versus patients with other types of cirrhosis (non-NAFLD). We studied 126 liver transplants performed between 2005 and 2007 at Saint Luc Hospital, University of Montreal. Seventeen of the 126 patients (13.5%) had NAFLD cirrhosis. Ascites volume was difficult to assess, so we used the body mass index (BMI) at 3 months as the reference BMI. All patients gained weight after transplantation, but BMI increased significantly more and earlier among the NAFLD patients [4.8 versus 1.5 kg/m(2) at 1 year (P = 0.001), 5.0 versus 2.3 kg/m(2) at 2 years (P = 0.01), and 5.6 versus 2.6 kg/m(2) at 5 years (P = 0.009)] in comparison with non-NAFLD patients in unadjusted analyses. The greatest BMI increase over time was investigated with univariate and multivariate logistic regression analyses. The BMI increase was divided into tertiles for each period of time observed. The greatest BMI increase over time was defined as the top tertile of BMI increase. After adjustments for potential confounders (ie, total cholesterol, diabetes, and length of hospital stay), NAFLD was no longer associated with a risk of a greater BMI increase [odds ratio (OR) = 3.73 at 1 year (P = 0.11), OR = 2.15 at 2 years (P = 0.34), and OR = 2.87 at 5 years (P = 0.30)]. These findings suggest the need for multidisciplinary, early, and close weight monitoring for all patients. All patients could benefit from pretransplant counseling regarding weight gain and its consequences.

Diabetes knowledge and self-management effects on physiological outcomes in type 2 diabetes

PURPOSE

The purpose of this study was to determine whether Asian Pacific Islanders with type 2 diabetes who have better knowledge and self-management would have better baseline hemoglobin A1c (HbA1c) and total cholesterol values. Signicant relationships were found among (a) general diet on HbA1c (p < .030), (b) medications on HbA1c (< .009), and (c) diabetes knowledge on HbA1c (p < .001). Participants with active self-management regimens were expected to demonstrate better laboratory values than those who did not implement self-management. However, persons with knowledge may for other reasons still lack self-management.

PRACTICAL IMPLICATIONS

Future studies comparing baseline results to post-additional education sessions may yield better comparisons.

Can exercise training rescue the adverse cardiometabolic effects of low birth weight and prematurity?

Being born preterm and/or small for gestational age are well-established risk factors for cardiometabolic disease in adulthood. Physical activity has the potential to mitigate against the detrimental cardiometabolic effects of low birth weight from two perspectives: (i) maternal exercise prior to and during pregnancy; and (ii) exercise during childhood or adulthood for those born small or prematurely. Evidence from epidemiological birth cohort studies suggests that the effects of moderate-intensity physical activity during pregnancy on mean birth weight are small, but reduce the risk of either high or low birth weight infants. In contrast, vigorous and/or high-intensity exercise during pregnancy has been associated with reduced birth weight. In childhood and adolescence, exercise ability is compromised in extremely low birth weight individuals (< 1000 g), but only marginally reduced in those of very low to low birth weight (1000-2500 g). Epidemiological studies show that the association between birth weight and metabolic disease is lost in physically fit individuals and, consistently, that the association between low birth weight and metabolic syndrome is accentuated in unfit individuals. Physical activity intervention studies indicate that most cardiometabolic risk factors respond to exercise in a protective manner, independent of birth weight. The mechanisms by which exercise may protect low birth weight individuals include restoration of muscle mass, reduced adiposity and enhanced β-cell mass and function, as well as effects on both aerobic and anaerobic muscle metabolism, including substrate utilization and mitochondrial function. Vascular and cardiac adaptations are also likely important, but are less well studied.

Duration of exercise as a key determinant of improvement in insulin sensitivity in type 2 diabetes patients

Exercise duration and intensity are important parameters in exercise prescription and play a major role in improving insulin sensitivity (including transient and persistent improvement effects following cessation of training) in patients with type 2 diabetes mellitus (T2DM). However, whether duration or intensity of exercise is the more important factor has yet to be established. Therefore, we aimed to determine whether exercise prescriptions differing in duration and intensity differ in their ability to aid T2DM patients to retain insulin sensitivity following the conclusion of a period of training. Sedentary T2DM patients (age 51.2 ± 1.3 years) were assigned to either a low-intensity (50% VO(2peak), n = 27) or a high-intensity exercise group (75% VO(2peak), n = 28), and followed a 12-week exercise program of 5 sessions/week and 240 kcal/session. Insulin sensitivity (oral glucose tolerance test, ISI) was measured when subjects were sedentary and at 16-24 h and 15 days after the final training bout. The low-intensity group spent more training time to training per exercise session than the high-intensity group (56.1 ± 3.0 min/session vs. 34.3 ± 2.4 min/session) (P < 0.01), but the total amount of energy expended was the same. ISI was increased in both groups 16-24 h after the final training session, but only the low-intensity group still had elevated ISI 15 days after the cessation of training. These findings suggest that in T2DM patients, the persistent training-induced improvements in insulin sensitivity may be more dependent on exercise duration than exercise intensity in regimens with the same level of energy expenditure.

A physiotherapist-delivered, combined exercise and pain coping skills training intervention for individuals with knee osteoarthritis: a pilot study

BACKGROUND

Osteoarthritis (OA) of the knee is associated with a number of physical and psychological impairments. Unfortunately, very few treatment strategies are capable of addressing both types of impairments concurrently. We performed a pilot, randomized controlled, proof of principle trial investigating the feasibility and effects of an intervention combining physical exercise and pain coping skills training (PCST).

METHODS

Twenty patients with a clinical and radiographical diagnosis of tibiofemoral OA were randomized to receive either 10 weeks of physiotherapist supervised exercises (lower limb strengthening and walking) combined with non-directive counseling (NDC) or the same exercise program delivered concurrently with PCST. Primary outcomes included self-reported pain and pain coping, while secondary outcomes included self efficacy and self-reported physical function.

RESULTS

Ten participants were randomized to each group and both groups exhibited significant improvements in isometric knee strength, self-reported knee pain and physical function, self efficacy for control of pain management and other arthritis symptoms. Only those in the exercise + PCST group reported statistically significant improvements in pain control coping and rational thinking. No between-group differences existed in any outcome (0.07 < p < 0.98). Based on our findings, 63 participants per group would be needed for future large-scale studies using similar outcome measures and design.

CONCLUSIONS

Our study showed that an intervention that combines exercise and PCST within the same treatment session and delivered by specially-trained physiotherapists is feasible and can improve both physical and psychological outcomes in individuals with knee OA.

LEVEL OF EVIDENCE

Level II Clinical Trials Registry number: ACTRN12609000623291.

Mechanistic studies of lifestyle interventions in type 2 diabetes

AIM: To investigate the effect of lifestyle interventions in the non-pharmacological management of type 2 diabetes via a mechanistic approach.

METHODS: A randomized controlled trial was carried out on 60 type 2 diabetic male and female volunteers that fulfilled the inclusion criteria, with their proper consent and permission of the International Electrotechnical Commission for 1 year. 30 patients were included in the test group and 30 patients in the control group. Demographic details, anthropometrical status, physical activity, food habits and blood glucose lipid profile of the volunteers were recorded at baseline, the test group was directed for lifestyle intervention and final blood glucose lipid data were collected at the end of one year of patient follow-up.

RESULTS: After 1 year, the test group who had a lifestyle intervention was found to show a significant improvement in blood glucose lipid profile. The fasting plasma glucose level (FPG), postprandial plasma glucose level (PPG), glycosylated hemoglobin (HbA1c) and body mass index (BMI) values of the test group were reduced significantly, up to 145 ± 2.52, 174 ± 2.59, 6.3 ± 0.32 and 25 ± 0.41 respectively at the end of the study period, in comparison to the control group where FPG, PPG, HbA1c and BMI values were 193 ± 3.36, 249 ± 4.24, 7.2 ± 0.42 and 26 ± 0.65 respectively. Improvement in the total cholesterol (TC), triglyceride (TG), high-density lipoproteins (HDL) and low-density lipoproteins (LDL) values of the test group was also remarkable in comparison to the control group. The TC, TG, HDL and LDL values of the test group were reduced significantly, up to 149 ± 3.32, 124 ± 2.16, 58 ± 0.62 and 118 ± 2.31, respectively.

CONCLUSION: The significant improvement in the blood glucose lipid profile of the test group after 1 year signifies the value of non-pharmacological management of type 2 diabetes via lifestyle intervention strategies.

Effects of supervised exercise on lipid profiles and blood pressure control in people with type 2 diabetes mellitus: a meta-analysis of randomized controlled trials

AIMS

Our study's purpose was to perform a systematic review to assess the effect of supervised exercise interventions on lipid profiles and blood pressure control.

METHODS

We searched electronic databases and selected studies that evaluated the effect of supervised exercise intervention on cardiovascular risk factors in adult people with type 2 diabetes. We used random effect models to derive weighted mean differences of exercise on lipid profiles and blood pressure control.

RESULTS

Forty-two RCTs (2808 subjects) met inclusion criteria and are included in our meta-analysis. Structured exercise was associated with a change in systolic blood pressure (SBP) of -2.42 mmHg (95% CI, -4.39 to -0.45 mmHg), diastolic blood pressure (DBP) of -2.23 mmHg (95% CI, -3.21 to -1.25 mmHg), high-density lipoprotein cholesterol (HDL-C) of 0.04 mmol/L (95% CI, 0.02-0.07 mmol/L), and low-density lipoprotein cholesterol (LDL-C) of -0.16 mmol/L (95% CI, -0.30 to -0.01 mmol/L). Heterogeneity was partially explained by age, dietary co-intervention and the duration and intensity of the exercise.

CONCLUSIONS

Supervised exercise is effective in improving blood pressure control, lowering LDL-C, and elevating HDL-C levels in people with diabetes. Physicians should recommend exercise for their adult patients with diabetes who can safely do so.

Genetic dissection of complex genetic factor involved in NIDDM of OLETF rat

The Otsuka Long-Evans Tokushima Fatty (OLETF) rat is an animal model for obese-type, noninsulin-dependent diabetes mellitus (NIDDM) in humans. NIDDM in this rat model was shown to be regulated by multiple genes. We have identified 14 quantitative trait loci (QTLs) responsible for NIDDM (Nidd1-14/of) on chromosomes 1, 5, 7, 8, 9, 11, 12, 14, 16, and 17 by a whole genome search in 160 F2 progenies obtained by mating the OLETF and the F344 rats. Among these loci, two QTLs, Nidd1 and 2/of, were declared significant loci at a genome-wide level. Nidd3, 8, 9, and 13/of exhibited heterosis: heterozygotes showing significantly higher glucose levels than OLETF or F344 homozygotes. We also found evidence for interaction (epistasis) between Nidd1/of and Nidd2/of, between Nidd1/of and Nidd10/of, between Nidd2/of and Nidd8/of, and between Nidd2/of and Nidd14/of. Furthermore, Nidd6 and 11/of showed linkage with body weight, and Nidd1, 2, 8, 9, 10, and 12/of had an interaction with body weight. These indicated that NIDDM in the OLETF would have a higher degree of genetic complexity. We suggest several interesting candidate genes located in rat genomic regions for Nidd1-14/of or the syntenic regions in human genome.

Physical Activity and Long-Term Maintenance of Weight Loss

To examine the effect of exercise on the long-term maintenance of weight loss, two types of literature were reviewed--correlational studies of predictors of long-term weight loss, and randomized trials comparing diet, exercise, and the combination of diet plus exercise. Both literatures were striking in the consistency with which activity emerged as a determinant of long-term maintenance of weight loss. The benefits of exercise for long-term weight maintenance were observed with different types of populations, diets, and exercise interventions. Several possible explanations for these positive effects of diet plus exercise are presented, and suggestions made for future research on ways to maximize the benefit of this approach to weight control. Since adherence to exercise may ultimately prove to be the cornerstone for long-term weight maintenance, studying ways to improve exercise adherence is recommended.

Dietary and Physical Activity Correlates of Long-Term Weight Loss

Covariations in body mass index (BMI), physical activity, macronutrient intake, and the frequency of consumption of specific foods were examined among 82 men and 75 women participating in a behavioral weight loss program over a period of 18 months. Results of repeated measures analyses of covariance showed that BMI change was inversely related to change in physical activity and change in frequency of vegetable consumption. BMI change was positively related to change in calorie intake from fat and change in frequency of consumption of beef, hot dogs, and sweets. Change in fat calories predicted BMI change better than change in total calories. In addition, change in the frequency of consumption of specific foods accounted for a larger percentage of the variance in BMI change than did change in macronutrients (10.4% vs. 5.2%). No differences were found between predictors of weight loss vs. weight maintenance.

Physical activity for obese individuals: a systematic review of effects on chronic disease risk factors

The purpose of this review was to determine the effectiveness of physical activity in improving chronic disease risk factors in obese individuals. A systematic review was conducted to identify randomized physical activity intervention studies reporting changes in risk factors among obese individuals published prior to March 2010. Studies included in the review were randomized trials of at least 10 weeks in duration, with a sample mean body mass index ≥ 30 kg/m(2) at baseline, and reporting a relevant risk factor (blood pressure, blood lipids, glucose/insulin or C-reactive protein). Forty-four studies met the inclusion criteria for this review. Overall, physical activity had no more than a modest effect on chronic disease risk factors in obese individuals. There was great heterogeneity in responses of risk factors across studies. In many studies it was difficult to determine the effect of physical activity, independent of changes in body mass consequent to the intervention. Obese individuals should be encouraged to undertake physical activity following general recommendations for weight loss and health. The degree to which physical activity is effective at lowering risk factor levels among high-risk obese individuals is not known.

Diet or diet plus physical activity versus usual care in patients with newly diagnosed type 2 diabetes: the Early ACTID randomised controlled trial

BACKGROUND

Lifestyle changes soon after diagnosis might improve outcomes in patients with type 2 diabetes mellitus, but no large trials have compared interventions. We investigated the effects of diet and physical activity on blood pressure and glucose concentrations.

METHODS

We did a randomised, controlled trial in southwest England in adults aged 30-80 years in whom type 2 diabetes had been diagnosed 5-8 months previously. Participants were assigned usual care (initial dietary consultation and follow-up every 6 months; control group), an intensive diet intervention (dietary consultation every 3 months with monthly nurse support), or the latter plus a pedometer-based activity programme, in a 2:5:5 ratio. The primary endpoint was improvement in glycated haemoglobin A(1c)(HbA(1c)) concentration and blood pressure at 6 months. Analysis was done by intention to treat. This study is registered, number ISRCTN92162869.

FINDINGS

Of 593 eligible individuals, 99 were assigned usual care, 248 the diet regimen, and 246 diet plus activity. Outcome data were available for 587 (99%) and 579 (98%) participants at 6 and 12 months, respectively. At 6 months, glycaemic control had worsened in the control group (mean baseline HbA(1c) percentage 6·72, SD 1·02, and at 6 months 6·86, 1·02) but improved in the diet group (baseline-adjusted difference in percentage of HbA(1c) -0·28%, 95% CI -0·46 to -0·10; p=0·005) and diet plus activity group (-0·33%, -0·51 to -0·14; p<0·001). These differences persisted to 12 months, despite less use of diabetes drugs. Improvements were also seen in bodyweight and insulin resistance between the intervention and control groups. Blood pressure was similar in all groups.

INTERPRETATION

An intensive diet intervention soon after diagnosis can improve glycaemic control. The addition of an activity intervention conferred no additional benefit.

FUNDING

Diabetes UK and the UK Department of Health.

Evidence-based risk assessment and recommendations for physical activity clearance: diabetes mellitus and related comorbidities1This paper is one of a selection of papers published in this Special Issue, entitled Evidence-based risk assessment and recommendations for physical activity clearance, and has undergone the Journal’s usual peer review process

Physical activity (PA) is one of the most powerful treatment options for persons with prediabetes or diabetes. However, some elevation in risk occurs with increased PA, at least initially, and certain precautions need to be made to lower these risks, particularly if these persons are unaccustomed to exercise. We conducted a standardized search of all adverse events associated with increased PA in persons with prediabetes or diabetes (type 1 or type 2) and provided evidence-based guidelines on PA screening in these apparently high-risk individuals. A systematic literature review was performed of all studies reporting on adverse events in persons with prediabetes or diabetes. Studies included were from all designs (retrospective and prospective including randomized controlled trials) and were assessed according to evaluation criteria adapted by a consensus panel. A total of 47 studies, involving >8000 individuals, were deemed eligible. A number of these studies identified a range of mild to severe acute risks with exercise (musculoskeletal injury, hypoglycemia, foot ulceration, proliferative retinopathy, hypotension, sudden death) but the overall prevalence was low. Based on several randomized controlled trials and prospective studies in which prescribed exercise was performed at a wide range of intensities, it appears that increased PA is a relatively safe procedure with no evidence of a loss of life. Based on our assessment of the available literature, we provide a new PA risk algorithm for persons with prediabetes and diabetes and comment on the role of the patient, the qualified exercise professional, and the patient’s physician in the risk screening process.

Diet and exercise for obese adults with knee osteoarthritis

Osteoarthritis (OA) is a common chronic disease and there is a need for treatments that can be provided for the course of the disease with minimal adverse side effects. Exercise is a safe intervention in patients with knee OA with few contraindications or adverse events. Obesity is the most modifiable risk factor for knee OA. The mechanisms by which obesity affects OA are of great concern to researchers and clinicians who manage this disease. This article reviews the physiologic and mechanical consequences of obesity and exercise on older adults with knee OA, the effects of long-term weight loss and exercise interventions, and the utility and feasibility of translating these results to clinical practice.

Lifestyle intervention for type 2 diabetes patients: trial protocol of The Copenhagen Type 2 Diabetes Rehabilitation Project

BACKGROUND

Current guidelines recommend education, physical activity and changes in diet for type 2 diabetes patients, yet the composition and organization of non-pharmacological care are still controversial. Therefore, it is very important that programmes aiming to improve non-pharmacological treatment of type 2 diabetes are developed and evaluated. The Copenhagen Type 2 Diabetes Rehabilitation Project aims to evaluate the effectiveness of a new group-based lifestyle rehabilitation programme in a Health Care Centre in primary care.

METHODS/DESIGN

The group-based diabetes rehabilitation programme consists of empowerment-based education, supervised exercise and dietary intervention. The effectiveness of this multi-disciplinary intervention is compared with conventional individual counselling in a Diabetes Outpatient Clinic and evaluated in a prospective and randomized controlled trial. During the recruitment period of 18 months 180 type 2 diabetes patients will be randomized to the intervention group and the control group. Effects on glycaemic control, quality of life, self-rated diabetes symptoms, body composition, blood pressure, lipids, insulin resistance, beta-cell function and physical fitness will be examined after 6, 12 and 24 months.

DISCUSSION

The Copenhagen Type 2 Diabetes Rehabilitation Project evaluates a multi-disciplinary non-pharmacological intervention programme in a primary care setting and provides important information about how to organize non-pharmacological care for type 2 diabetes patients.

TRIAL REGISTRATION

(ClinicalTrials.gov) registration number: NCT00284609.

Lipoprotein profile, glycemic control and physical fitness after strength and aerobic training in post-menopausal women with type 2 diabetes

We studied the effects on blood lipids and physical fitness after a training program that combined strength and aerobic exercise in postmenopausal women with type 2 diabetes. Ten patients (55.0 +/- 5.2 years) followed four exercise sessions per week, two strength and two aerobic, and ten (59.4 +/- 3.2 years) served as a control group. Lipid profile, glycated hemoglobin (HbA(1c)), HOMA2 index, exercise stress and muscular testing were assessed at the beginning and after 16 weeks of training program. Exercise training increased significantly HDL-C (17.2%; P < 0.001) and decreased triglycerides (18.9%), HbA(1c) (15.0%), fasting plasma glucose (5.4%), insulin resistance (HOMA2 25.2%) and resting blood pressure (P < 0.01). After 16 weeks of training, exercise time (17.8%) and muscular strength increased significantly (P < 0.001). The results indicated that a combined strength and aerobic training program could induce positive adaptations on lipid profile, glycemic control, insulin resistance, cardiovascular function, and physical fitness in post-menopausal women with type 2 diabetes.

Long-term effectiveness of diet-plus-exercise interventions vs. diet-only interventions for weight loss: a meta-analysis

Diet and exercise are two of the commonest strategies to reduce weight. Whether a diet-plus-exercise intervention is more effective for weight loss than a diet-only intervention in the long-term has not been conclusively established. The objective of this study was to systemically review the effect of diet-plus-exercise interventions vs. diet-only interventions on both long-term and short-term weight loss. Studies were retrieved by searching MEDLINE and Cochrane Library (1966 - June 2008). Studies were included if they were randomized controlled trials comparing the effect of diet-plus-exercise interventions vs. diet-only interventions on weight loss for a minimum of 6 months among obese or overweight adults. Eighteen studies met our inclusion criteria. Data were independently extracted by two investigators using a standardized protocol. We found that the overall standardized mean differences between diet-plus-exercise interventions and diet-only interventions at the end of follow-up were -0.25 (95% confidence interval [CI]-0.36 to -0.14), with a P-value for heterogeneity of 0.4. Because there were two outcome measurements, weight (kg) and body mass index (kg m(-2)), we also stratified the results by weight and body mass index outcome. The pooled weight loss was 1.14 kg (95% CI 0.21 to 2.07) or 0.50 kg m(-2) (95% CI 0.21 to 0.79) greater for the diet-plus-exercise group than the diet-only group. We did not detect significant heterogeneity in either stratum. Even in studies lasting 2 years or longer, diet-plus-exercise interventions provided significantly greater weight loss than diet-only interventions. In summary, a combined diet-plus-exercise programme provided greater long-term weight loss than a diet-only programme. However, both diet-only and diet-plus-exercise programmes are associated with partial weight regain, and future studies should explore better strategies to limit weight regain and achieve greater long-term weight loss.

Patients with Type 2 Diabetes experiences of making multiple lifestyle changes: a qualitative study

OBJECTIVES

To explore patients newly diagnosed with Type 2 Diabetes Mellitus (T2DM) experiences of making single (diet) or multiple (diet and physical activity) changes in order to (1) assess whether patients experienced increases in physical activity as supporting or hindering dietary changes and vice versa, and (2) whether patients found making multiple lifestyle changes counterproductive or beneficial.

METHODS

In-depth interviews with 30 individuals taking part in a randomised controlled trial that aimed to determine the effect of diet and physical activity on T2DM. Interviewees had been randomised to receive usual care, intensive dietary advice, or intensive dietary advice plus information on physical activity. Respondents were interviewed 6 and 9 months post-randomisation. They were asked about their experiences of making lifestyle changes. Data were analysed thematically.

RESULTS

Findings suggest providing diet and physical activity information together encourages patients to use physical activity in strategic ways to aid disease management and that most patients find undertaking multiple lifestyle changes helpful.

CONCLUSION

Increasing physical activity can act as a gateway behaviour, i.e. behaviour that produces positive effects in other behaviours.

PRACTICE IMPLICATIONS

Practitioners should provide diet and physical activity information together to encourage patients to use physical activity strategically to maintain dietary changes.

Obesity and osteoarthritis: disease genesis and nonpharmacologic weight management

The mechanisms by which obesity affects osteoarthritis (OA) are of great concern to osteoarthritis researchers and clinicians who manage this disease. Inflammation and joint loads are pathways commonly believed to cause or to exacerbate the disease process. This article reviews the physiologic and mechanical consequences of obesity in older adults who have knee OA, the effects of long-term exercise and weight-loss interventions, the most effective nonpharmacologic treatments for obesity, and the usefulness and feasibility of translating these results to clinical practice.

Intermittent versus continuous exercise: effects of perceptually lower exercise in obese women

INTRODUCTION

Exercise has beneficial effects on obesity and diabetes treatments. However, obese subjects do not closely adhere to training programs probably because of the monotony of the continuous exercise that is frequently proposed. To increase adherence to training programs, intermittent exercise, which is less monotonous, may be more appropriate.

PURPOSE

The purposes of this study were to determine the perceptually less hard exercise (continuous vs intermittent exercise) and to analyze the impact of a training program on the basis of this exercise in obese women with and without type 2 diabetes.

METHODS

Twenty type 2 diabetic obese women and 20 obese women without diabetes were recruited. In each group, 10 patients integrated a training program (i.e., training groups), whereas the remaining patients were untrained (i.e., control groups). The training groups performed a continuous exercise and an intermittent exercise to determine the perceptually less hard exercise thanks to lower ratings of perceived exertion (RPE). Then, a training program that included 32 min (3 d x wk(-1) x 10 wk(-1)) of the perceptually less hard exercise was proposed to training groups.

RESULTS

RPE were significantly lower during the intermittent exercise compared to the continuous exercise in the obese women with or without diabetes (RPE = 12.3 +/- 2.3 vs 13.7 +/- 2.3 and RPE = 11.9 +/- 1.1 vs 13.2 +/- 1.6, respectively). After the training program, significant beneficial effects on the glycosylated hemoglobin (6.8 +/- 1.4% vs 6.5 +/- 1.2%), body mass (97.1 +/- 16.9 vs 95.2 +/- 16.2 kg), body mass index (37.6 +/- 6.1 vs 36.8 +/- 6.0 kg x m(-2)), and on the HR and the walked distance limit were noticed in the training groups.

CONCLUSION

The obese women with or without diabetes perceived the intermittent exercise as being less hard than the continuous exercise, and a training program based on intermittent exercises produced beneficial effects on obesity and type 2 diabetes.

Determinants of changes in blood glucose response to short-term exercise training in patients with Type 2 diabetes

The aim of the present study was to determine the effects of a 4-week exercise training intervention on blood glucose, insulin sensitivity, BMI (body mass index) and cardiorespiratory fitness in patients with Type 2 diabetes, and to identify and establish criteria for patients who are more likely to improve their blood glucose from short-term exercise training. A randomized, controlled trial of exercise training, comprising two supervised and one non-supervised sessions of individualized cardiorespiratory and resistance exercise per week, was performed in 132 healthy patients with Type 2 diabetes (exercise training group, n=68), with the aim of accumulating a minimum of 150 min of moderate-intensity exercise for 4 weeks. BMI, waist circumference, blood pressure, blood lipid profile, blood glucose, insulin, insulin sensitivity [calculated by HOMA(IR) (homoeostasis model assessment of insulin resistance) and QUICKI (quantitative insulin check index)], beta-cell function (calculated by HOMA(beta-Cell)), HbA(1c) (glycated haemoglobin) and VO(2max) (maximal oxygen consumption) were measured at baseline and at 4 weeks. The exercise training group had significant improvements in VO(2max), BMI and triacylglycerols (triglycerides). There were no significant changes in blood glucose, HOMA(IR), QUICKI or HOMA(beta-Cell). Decreases in blood glucose were significantly predicted by baseline blood glucose and HbA(1c), with these variables accounting for 15.9% of the change in blood glucose (P<0.001). ROC (receiver operator characteristic) curve analysis revealed that patients with a blood glucose >8.85 mmol/l (sensitivity=73%, specificity=78%) and HbA(1c) >7.15% (sensitivity=79%, specificity=60%) were more likely to achieve a clinically significant decrease in blood glucose. In conclusion, in apparently healthy patients with Type 2 diabetes, a 4-week exercise intervention improved cardiorespiratory fitness, BMI and triacylglycerols. Elevated blood glucose and HbA(1c) predicted improvements in blood glucose.

Menopause, the metabolic syndrome, and mind-body therapies

Cardiovascular disease risk rises sharply with menopause, likely due to the coincident increase in insulin resistance and related atherogenic changes that together comprise the metabolic or insulin resistance syndrome, a cluster of metabolic and hemodynamic abnormalities strongly implicated in the pathogenesis and progression of cardiovascular disease. A growing body of research suggests that traditional mind-body practices such as yoga, tai chi, and qigong may offer safe and cost-effective strategies for reducing insulin resistance syndrome-related risk factors for cardiovascular disease in older populations, including postmenopausal women. Current evidence suggests that these practices may reduce insulin resistance and related physiological risk factors for cardiovascular disease; improve mood, well-being, and sleep; decrease sympathetic activation; and enhance cardiovagal function. However, additional rigorous studies are needed to confirm existing findings and to examine long-term effects on cardiovascular health.

Obesity and osteoarthritis: disease genesis and nonpharmacologic weight management

The mechanisms by which obesity affects osteoarthritis (OA) are of great concern to osteoarthritis researchers and clinicians who manage this disease. Inflammation and joint loads are pathways commonly believed to cause or to exacerbate the disease process. This article reviews the physiologic and mechanical consequences of obesity in older adults who have knee OA, the effects of long-term exercise and weight-loss interventions, the most effective nonpharmacologic treatments for obesity, and the usefulness and feasibility of translating these results to clinical practice.

Does home-based exercise improve body mass index in patients with type 2 diabetes? Results of a feasibility trial

AIMS

This feasibility trial evaluated the use, safety, and short-term benefits of a home-based exercise intervention designed to increase physical activity among adults with diabetes.

METHODS

Participants with type 2 diabetes in a group practice were recruited and randomly assigned to the home-based exercise intervention or usual care. Participants were given diabetes self-management education, instructed to exercise 30 min 5 days/week, and were followed for 3 months. The intervention contained three exercise routines (aerobic and resistance exercises). Outcomes included changes from baseline at 3 months between groups in body mass index (BMI), quality of life, A1C, and blood pressure.

RESULTS

Seventy-six sedentary adults completed the study: 49% intervention group, 68% women, 47% black, mean age 56.6+/-9.6 years. Using intention to treat analysis, a trend towards improvement between groups for BMI (mean change -0.4 versus 0.1, respectively; P=0.06) was identified. Thirty-eight percent of the intervention group adhered to 80% of the exercise recommendation and significantly improved BMI (-1.07; P<0.05). No other differences were detected between groups.

CONCLUSIONS

Home-based exercise interventions have potential to reduce BMI in patients with diabetes. The results provide variance estimates necessary to power a larger study of longer duration.

Metabolic syndrome and type 2 diabetes: can we stop the weight gain with diabetes?

Many patients with type 2 diabetes also have the metabolic syndrome with its cardinal features of central adiposity, insulin resistance, dyslipidemia, and hypertension. Although there is strong evidence for the importance of tight glycemic control in minimizing the microvascular complications of diabetes, many of the current therapies used for optimizing glycemic control also cause weight gain. With this treatment-induced weight gain, there is a risk of worsening the patient's insulin resistance. Physicians need to be aware of this vicious cycle in their overweight type 2 diabetic patients. This article reviews the strategies currently available to achieve glycemic control while at the same time minimizing weight gain and the associated complications.

Dietary advice for treatment of type 2 diabetes mellitus in adults

BACKGROUND

While initial dietary management immediately after formal diagnosis is an 'accepted' cornerstone of treatment of type 2 diabetes mellitus, a formal and systematic overview of its efficacy and method of delivery is not currently available.

OBJECTIVES

To assess the effects of type and frequency of different types of dietary advice for adults with type 2 diabetes.

SEARCH STRATEGY

We carried out a comprehensive search of The Cochrane Library, MEDLINE, EMBASE, CINAHL, AMED, bibliographies and contacted relevant experts.

SELECTION CRITERIA

All randomised controlled trials, of six months or longer, in which dietary advice was the main intervention.

DATA COLLECTION AND ANALYSIS

The lead investigator performed all data extraction and quality scoring with duplication being carried out by one of the other six investigators independently with discrepancies resolved by discussion and consensus. Authors were contacted for missing data.

MAIN RESULTS

Thirty-six articles reporting a total of eighteen trials following 1467 participants were included. Dietary approaches assessed in this review were low-fat/high-carbohydrate diets, high-fat/low-carbohydrate diets, low-calorie (1000 kcal per day) and very-low-calorie (500 kcal per day) diets and modified fat diets. Two trials compared the American Diabetes Association exchange diet with a standard reduced fat diet and five studies assessed low-fat diets versus moderate fat or low-carbohydrate diets. Two studies assessed the effect of a very-low-calorie diet versus a low-calorie diet. Six studies compared dietary advice with dietary advice plus exercise and three other studies assessed dietary advice versus dietary advice plus behavioural approaches. The studies all measured weight and measures of glycaemic control although not all studies reported these in the articles published. Other outcomes which were measured in these studies included mortality, blood pressure, serum cholesterol (including LDL and HDL cholesterol), serum triglycerides, maximal exercise capacity and compliance. The results suggest that adoption of regular exercise is a good way to promote better glycaemic control in type 2 diabetic patients, however all of these studies were at high risk of bias.

AUTHORS' CONCLUSIONS

There are no high quality data on the efficacy of the dietary treatment of type 2 diabetes, however the data available indicate that the adoption of exercise appears to improve glycated haemoglobin at six and twelve months in people with type 2 diabetes. There is an urgent need for well-designed studies which examine a range of interventions, at various points during follow-up, although there is a promising study currently underway.

The role of physical activity in producing and maintaining weight loss

The majority of randomized, controlled trials (RCTs) show only modest weight loss with exercise intervention alone, and slight increases in weight loss when exercise intervention is added to dietary restriction. In most RCTs, the energy deficit produced by the prescribed exercise is far smaller than that usually produced by dietary restriction. In prospective studies that prescribed high levels of exercise, enrolled individuals achieved substantially greater weight loss-comparable to that obtained after similar energy deficits were produced by caloric restriction. High levels of exercise might, however, be difficult for overweight or obese adults to achieve and sustain. RCTs examining exercise and its effect on weight-loss maintenance demonstrated mixed results; however, weight maintenance interventions were usually of limited duration and long-term adherence to exercise was problematic. Epidemiologic, cross-sectional, and prospective correlation studies suggest an essential role for physical activity in weight-loss maintenance, and post hoc analysis of prospective trials shows a clear dose-response relationship between physical activity and weight maintenance. This article reviews the role of physical activity in producing and maintaining weight loss. We focus on prospective, RCTs lasting at least 4 months; however, other prospective trials, meta-analyses and large systematic reviews are included. Limitations in the current body of literature are discussed.

Effects of different modes of exercise training on glucose control and risk factors for complications in type 2 diabetic patients: a meta-analysis

OBJECTIVE

We sought to meta-analyze the effects of different modes of exercise training on measures of glucose control and other risk factors for complications of diabetes.

RESEARCH DESIGN AND METHODS

The 27 qualifying studies were controlled trials providing, for each measure, 4-18 estimates for the effect of aerobic training, 2-7 for resistance training, and 1-5 for combined training, with 1,003 type 2 diabetic patients (age 55 +/- 7 years [mean +/- between-study SD]) over 5-104 weeks. The meta-analytic mixed model included main-effect covariates to control for between-study differences in disease severity, sex, total training time, training intensity, and dietary cointervention (13 studies). To interpret magnitudes, effects were standardized after meta-analysis using composite baseline between-subject SD.

RESULTS

Differences among the effects of aerobic, resistance, and combined training on HbA(1c) (A1C) were trivial; for training lasting >/=12 weeks, the overall effect was a small beneficial reduction (A1C 0.8 +/- 0.3% [mean +/- 90% confidence limit]). There were generally small to moderate benefits for other measures of glucose control. For other risk factors, there were either small benefits or effects were trivial or unclear, although combined training was generally superior to aerobic and resistance training. Effects of covariates were generally trivial or unclear, but there were small additional benefits of exercise on glucose control with increased disease severity.

CONCLUSIONS

All forms of exercise training produce small benefits in the main measure of glucose control: A1C. The effects are similar to those of dietary, drug, and insulin treatments. The clinical importance of combining these treatments needs further research.

Exercise for overweight or obesity

BACKGROUND

Clinical trials have shown that exercise in adults with overweight or obesity can reduce bodyweight. There has been no quantitative systematic review of this in The Cochrane Library.

OBJECTIVES

To assess exercise as a means of achieving weight loss in people with overweight or obesity, using randomised controlled clinical trials.

SEARCH STRATEGY

Studies were obtained from computerised searches of multiple electronic bibliographic databases. The last search was conducted in January 2006.

SELECTION CRITERIA

Studies were included if they were randomised controlled trials that examined body weight change using one or more physical activity intervention in adults with overweight or obesity at baseline and loss to follow-up of participants of less than 15%.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data.

MAIN RESULTS

The 43 studies included 3476 participants. Although significant heterogeneity in some of the main effects' analyses limited ability to pool effect sizes across some studies, a number of pooled effect sizes were calculated. When compared with no treatment, exercise resulted in small weight losses across studies. Exercise combined with diet resulted in a greater weight reduction than diet alone (WMD -1.1 kg; 95% confidence interval (CI) -1.5 to -0.6). Increasing exercise intensity increased the magnitude of weight loss (WMD -1.5 kg; 95% CI -2.3 to -0.7). There were significant differences in other outcome measures such as serum lipids, blood pressure and fasting plasma glucose. Exercise as a sole weight loss intervention resulted in significant reductions in diastolic blood pressure (WMD -2 mmHg; 95% CI -4 to -1), triglycerides (WMD -0.2 mmol/L; 95% CI -0.3 to -0.1) and fasting glucose (WMD -0.2 mmol/L; 95% CI -0.3 to -0.1). Higher intensity exercise resulted in greater reduction in fasting serum glucose than lower intensity exercise (WMD -0.3 mmol/L; 95% CI -0.5 to -0.2). No data were identified on adverse events, quality of life, morbidity, costs or on mortality.

AUTHORS' CONCLUSIONS

The results of this review support the use of exercise as a weight loss intervention, particularly when combined with dietary change. Exercise is associated with improved cardiovascular disease risk factors even if no weight is lost.

Evidence for prescribing exercise as therapy in chronic disease

Considerable knowledge has accumulated in recent decades concerning the significance of physical activity in the treatment of a number of diseases, including diseases that do not primarily manifest as disorders of the locomotive apparatus. In this review we present the evidence for prescribing exercise therapy in the treatment of metabolic syndrome-related disorders (insulin resistance, type 2 diabetes, dyslipidemia, hypertension, obesity), heart and pulmonary diseases (chronic obstructive pulmonary disease, coronary heart disease, chronic heart failure, intermittent claudication), muscle, bone and joint diseases (osteoarthritis, rheumatoid arthritis, osteoporosis, fibromyalgia, chronic fatigue syndrome) and cancer, depression, asthma and type 1 diabetes. For each disease, we review the effect of exercise therapy on disease pathogenesis, on symptoms specific to the diagnosis, on physical fitness or strength and on quality of life. The possible mechanisms of action are briefly examined and the principles for prescribing exercise therapy are discussed, focusing on the type and amount of exercise and possible contraindications.

Exercise for type 2 diabetes mellitus

BACKGROUND

Exercise is generally recommended for people with type 2 diabetes mellitus. However, some studies evaluate an exercise intervention including diet or behaviour modification or both, and the effects of diet and exercise are not differentiated. Some exercise studies involve low participant numbers, lacking power to show significant differences which may appear in larger trials.

OBJECTIVES

To assess the effects of exercise in type 2 diabetes mellitus.

SEARCH STRATEGY

Trials were identified through the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and manual searches of bibliographies. Date of last search was March 3, 2005.

SELECTION CRITERIA

All randomised controlled trials comparing any type of well-documented aerobic, fitness or progressive resistance training exercise with no exercise in people with type 2 diabetes mellitus.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, assessed trial quality and extracted data. Study authors were contacted for additional information. Any information on adverse effects was collected from the trials.

MAIN RESULTS

Fourteen randomised controlled trials comparing exercise against no exercise in type 2 diabetes were identified involving 377 participants. Trials ranged from eight weeks to twelve months duration. Compared with the control, the exercise intervention significantly improved glycaemic control as indicated by a decrease in glycated haemoglobin levels of 0.6% (-0.6 % HbA(1c), 95% confidence interval (CI) -0.9 to -0.3; P < 0.05). This result is both statistically and clinically significant. There was no significant difference between groups in whole body mass, probably due to an increase in fat free mass (muscle) with exercise, as reported in one trial (6.3 kg, 95% CI 0.0 to 12.6). There was a reduction in visceral adipose tissue with exercise (-45.5 cm(2), 95% CI -63.8 to -27.3), and subcutaneous adipose tissue also decreased. No study reported adverse effects in the exercise group or diabetic complications. The exercise intervention significantly increased insulin response (131 AUC, 95% CI 20 to 242) (one trial), and decreased plasma triglycerides (-0.25 mmol/L, 95% CI -0.48 to -0.02). No significant difference was found between groups in quality of life (one trial), plasma cholesterol or blood pressure.

AUTHORS' CONCLUSIONS

The meta-analysis shows that exercise significantly improves glycaemic control and reduces visceral adipose tissue and plasma triglycerides, but not plasma cholesterol, in people with type 2 diabetes, even without weight loss.