Physical activity in prevention and treatment of the metabolic syndrome

Use of a Web-based physical activity record system to analyze behavior in a large population: cross-sectional study

Background

The use of Web-based physical activity systems has been proposed as an easy method for collecting physical activity data. We have developed a system that has exhibited high accuracy as assessed by the doubly labeled water method.

Objective

The purpose of this study was to collect behavioral data from a large population using our Web-based physical activity record system and assess the physical activity of the population based on these data. In this paper, we address the difference in physical activity for each urban scale.

Methods

In total, 2046 participants (aged 30-59 years; 1105 men and 941 women) participated in the study. They were asked to complete data entry before bedtime using their personal computer on 1 weekday and 1 weekend day. Their residential information was categorized as urban, urban-rural, or rural. Participant responses expressed the intensity of each activity at 15-minute increments and were recorded on a Web server. Residential areas were compared and multiple regression analysis was performed.

Results

Most participants had a metabolic equivalent (MET) ranging from 1.4 to 1.8, and the mean MET was 1.60 (SD 0.28). The median value of moderate-to-vigorous physical activity (MVPA, ≥3 MET) was 7.92 MET-hours/day. A 1-way ANCOVA showed that total physical activity differed depending on the type of residential area (F_2,2027=5.19, P=.006). The urban areas (n=950) had the lowest MET-hours/day (mean 37.8, SD, 6.0), followed by urban-rural areas (n=432; mean 38.6, SD 6.5; P=.04), and rural areas (n=664; mean 38.8, SD 7.4; P=.002). Two-way ANCOVA showed a significant interaction between sex and area of residence on the urban scale (F_2,2036=4.53, P=.01). Men in urban areas had the lowest MET-hours/day (MVPA, ≥3 MET) at mean 7.9 (SD 8.7); men in rural areas had a MET-hours/day (MVPA, ≥3 MET) of mean 10.8 (SD 12.1, P=.002). No significant difference was noted in women among the 3 residential areas. Multiple regression analysis showed that physical activity consisting of standing while working was the highest contributor to MVPA, regardless of sex.

Conclusions

We were able to compile a detailed comparison of physical activity because our Web-based physical activity record system allowed for the simultaneous evaluation of physical activity from 2046 Japanese people. We found that rural residents had greater total physical activity than urban residents and that working and transportation behaviors differed depending on region type. Multiple regression analysis showed that the behaviors affected MVPA. People are less physically active while working, and sports and active transportation might be effective ways of increasing physical activity levels.

Physical activity patterns and metabolic syndrome in Costa Rica

OBJECTIVE

To examine whether total physical activity or activity patterns are associated with metabolic syndrome and its components.

METHODS

Participants include 1994 controls from a case-control study of non-fatal myocardial infarction in Costa Rica (1994-2004). Physical activity was assessed via self-administered questionnaire and patterns were identified using principal components analysis. Metabolic syndrome was assessed via blood samples and anthropometry measurements from in-home study visits. Prevalence ratios (PRs) and 95% confidence intervals (CIs) were calculated using log binomial regression. Adjusted least squares means of metabolic syndrome components were calculated by quintile of total activity and pattern scores.

RESULTS

Four activity patterns were identified: rest/sleep, agricultural, light indoor activity, and manual labor. Total activity was not associated with metabolic syndrome. Metabolic syndrome prevalence was 20% lower in participants with the highest scores on the agricultural job pattern compared to those with the lowest (PR: 0.80, 95% CI: 0.68-0.94). Higher total activity was associated with lower triglycerides and lower HDL cholesterol. Higher scores on each pattern were inversely associated with metabolic syndrome components, particularly waist circumference and fasting blood glucose.

CONCLUSIONS

Patterns or types of physical activity may be more strongly associated with metabolic syndrome and its components than total activity levels.

Effects of 1-year yoga on cardiovascular risk factors in middle-aged and older adults with metabolic syndrome: a randomized trial

BACKGROUND

Metabolic syndrome (MetS) is a clustering of cardiovascular risk factors, which is associated with diabetes mellitus and cardiovascular disease. Lifestyle interventions applied to people with MetS has considerable beneficial effects on disease preventive outcomes. This study aimed to examine the effects of 1-year of yoga exercise on the cardiovascular risk factors including central obesity, hypertension, dyslipidemia and hyperglycemia in middle-aged and older Hong Kong Chinese adults with MetS.

METHODS

Adults diagnosed with MetS using National Cholesterol Education Program criteria (n = 182; mean ± SD age = 56 ± 9.1) were randomly assigned to a 1-year yoga intervention group or control group. Systolic and diastolic blood pressure, waist circumference, fasting plasma glucose, triglycerides, and high-density lipoprotein cholesterol were examined at baseline, midway, and on completion of the study. Physical activity level and caloric intake were assessed and included in the covariate analyses.

RESULTS

A reduction of the number of diagnostic components for MetS was found to be associated with the yoga intervention. Waist circumference was significantly improved after the 1-year yoga intervention. A trend towards a decrease in systolic blood pressure was observed following yoga intervention.

CONCLUSION

These results suggest that yoga exercise improves the cardiovascular risk factors including central obesity and blood pressure in middle-aged and older adults with MetS. These findings support the complementary beneficial role of yoga in managing MetS.

Diet and physical activity in relation to metabolic syndrome among urban Indian men and women

The relationship of diet and physical activity with metabolic syndrome (MS) was studied among 60 male and female (40-60 y) urban Indian MS patients. Intake of green leafy vegetables, other vegetables, fruits and milk were significantly (p ≤ .01) associated with reduced fat mass and waist circumference and increased lean body mass. Energy, carbohydrates, and fat intakes were significantly (p ≤ .01) correlated with increased body fat and waist circumference and reduced lean body mass. Energy, total and saturated fat intake were positively and significantly (p ≤ .05; .01) correlated with total cholesterol. Total fat was also significantly (p ≤ .05; .01) correlated with increased systolic blood pressure (r = 0.33), serum triglycerides (r = 0.33), LDL-C (r = 0.29) and VLDL-C (r = 0.28). Increased TDEE was significantly (p ≤ .01) associated with decreased body fat and waist circumference (r = 0.53 and 0.60) and increased lean body mass (r = 0.68).

Influence of aerobic training and detraining on serum BDNF, insulin resistance, and metabolic risk factors in middle-aged men diagnosed with metabolic syndrome

OBJECTIVE

To study the influence of aerobic exercise training on brain-derived neurotrophic factor (BDNF), insulin resistance, and lipid profile in middle-aged men diagnosed with metabolic syndrome (MetS).

DESIGN

This is an experimental repeated measure study.

SETTING

Subjects participated in aerobic training programs (18 sessions of 25-40 minutes per session) in Guilan University gymnasium and court.

PARTICIPANTS

A total of 21 middle-aged men (50-65 years old) diagnosed with MetS participated.

INTERVENTIONS

We randomly divided 21 middle-aged men with MetS into exercise and control groups. The exercise group followed an aerobic training program (18 sessions, 3/wk) at 50% to 60% of V[Combining Dot Above]O2 peak (25-40 minutes per session) and 6 weeks of detraining. Blood samples were collected at baseline, end of the training, and detraining.

MAIN OUTCOME MEASURES

High BDNF level in patients with MetS and its reduction after chronic aerobic exercise.

RESULTS

Aerobic training significantly decreased all the metabolic risk factors, including overall MetS z score, insulin resistance, and lipid profile (P < 0.05). After the detraining period, plasma triglyceride, high-density lipoprotein, and also overall MetS z score remained unchanged (P < 0.05); however, serum BDNF, which was decreased by aerobic training (P = 0.013), restored to the baseline at the end of the detraining (P = 0.018).

CONCLUSIONS

Improved metabolic risk factors along with decreased serum BDNF in response to aerobic training and the opposite direction during the detraining emphasize the importance of physical activity in the treatment of MetS and prevention of related diseases.

Potential transferability of economic evaluations of programs encouraging physical activity in children and adolescents across different countries--a systematic review of the literature

Physical inactivity is an increasing problem. Owing to limited financial resources, one method of getting information on the cost-effectiveness of different types of prevention programs is to examine existing programs and their results. The aim of this paper is to give an overview of the transferability of cost-effectiveness results of physical activity programs for children and adolescents to other contexts. Based on a systematic review of the literature, the transferability of the studies found was assessed using a sub-checklist of the European Network of Health Economic Evaluation Databases (EURONHEED). Thirteen studies of different physical activity interventions were found and analyzed. The results for transferability ranged from “low” to “very high”. A number of different factors influence a program’s cost-effectiveness (i.e., discount rate, time horizon, etc.). Therefore, transparency with regard to these factors is one fundamental element in the transferability of the results. A major point of criticism is that transferability is often limited because of lack of transparency. This paper is the first to provide both an overview and an assessment of transferability of economic evaluations of existing programs encouraging physical activity in children and adolescents. This allows decision makers to gain an impression on whether the findings are transferable to their decision contexts, which may lead to time and cost savings.

Combined effect of physical activity and leisure time sitting on long-term risk of incident obesity and metabolic risk factor clustering

AIMS/HYPOTHESIS

Our study aimed to investigate the combined effects of moderate-to-vigorous physical activity and leisure time sitting on the long-term risk of obesity and clustering of metabolic risk factors.

METHODS

The duration of moderate and vigorous physical activity and of leisure time sitting was assessed by questionnaire between 1997 and 1999 among 3,670 participants from the Whitehall II cohort study (73% male; mean age 56 years). Multivariable-adjusted logistic regression models examined associations of physical activity and leisure time sitting tertiles with odds of incident obesity (BMI ≥ 30 kg/m(2)) and incident metabolic risk factor clustering (two or more of the following: low HDL-cholesterol, high triacylglycerol, hypertension, hyperglycaemia, insulin resistance) at 5 and 10 year follow-ups.

RESULTS

Physical activity, but not leisure time sitting, was associated with incident obesity. The lowest odds of incident obesity after 5 years were observed for individuals reporting both high physical activity and low leisure time sitting (OR = 0.26; 95% CI 0.11, 0.64), with weaker effects after 10 years. Compared with individuals in the low physical activity/high leisure time sitting group, those with intermediate levels of both physical activity and leisure time sitting had lower odds of incident metabolic risk factor clustering after 5 years (OR 0.53; 95% CI 0.36, 0.78), with similar odds after 10 years.

CONCLUSIONS/INTERPRETATION

Both high levels of physical activity and low levels of leisure time sitting may be required to substantially reduce the risk of obesity. Associations with developing metabolic risk factor clustering were less clear.

Sporadic and bouted physical activity and the metabolic syndrome in adults

PURPOSE

Physical activity guidelines recommend that adults accumulate at least 150 min of moderate-to-vigorous physical activity (MVPA) per week in bouts of at least 10 min. However, sporadic MVPA contributes significantly to total physical activity and may also affect health. The study objective was to determine, within adults age 18 to 64 yr, whether MVPA accumulated in bouts is more strongly associated with metabolic syndrome (MetS) than an equivalent volume of MVPA accumulated sporadically.

METHODS

The study sample included 1119 adults age 18 to 64 yr from the 2007-2009 Canadian Health Measures Survey, a nationally representative cross-sectional study. The energy expenditure from bouted (at least 10 consecutive minutes) and sporadic (<10 consecutive minutes) MVPA was measured for 7 d using Actical accelerometers. The presence of MetS was determined using established criteria. Associations were examined using logistic regression and controlled for covariates (age, sex, education, diet, and smoking).

RESULTS

After adjusting for the covariates and each other, bouted and sporadic MVPA were independently associated with the MetS. For each additional MET-hour per week of bouted MVPA, the relative odds of the MetS decreased by 9% (95% confidence interval, 3%-14%). For each additional MET-hour per week of sporadic MVPA, the relative odds of the MetS decreased by 11% (5%-16%). Overlapping confidence interval indicates no difference in the effect estimates for bouted and sporadic MVPA. Secondary analyses revealed that small bursts of sporadic MVPA (1-3 min) were meaningful when predicting the MetS.

CONCLUSION

Within this representative sample of Canadian adults, sporadic MVPA was associated with the MetS to a similar order of magnitude as an equivalent volume of bouted MVPA.

Cut points of muscle strength associated with metabolic syndrome in men

INTRODUCTION

The loss of muscle strength with age increases the likelihood of chronic conditions, including metabolic syndrome (MetS). However, the minimal threshold of muscle strength at which the risk for MetS increases has never been established.

OBJECTIVE

This study aimed to identify a threshold of muscle strength associated with MetS in men.

METHODS

We created receiver operating curves for muscle strength and the risk of MetS from a cross-sectional sample of 5685 men age <50 yr and 1541 men age ≥50 yr enrolled in the Aerobics Center Longitudinal Study. The primary outcome measure, the MetS, was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Upper and lower body muscle strength was treated as a composite measure of one-repetition maximum tests on bench and leg press and scaled to body weight. Low muscle strength was defined as the lowest age-specific 20th percentile, whereas high muscle strength was defined as composite muscle strength above the 20th percentile.

RESULTS

In men aged <50 yr, the odds of MetS were 2.20-fold (95% confidence interval = 1.89-2.54) higher in those with low muscle strength, independent of age, smoking, and alcohol intake. The strength of this association was similar for men age ≥50 yr (odds ratio = 2.11, 95% confidence interval = 1.62-2.74). In men age < 50 yr, the composite strength threshold associated with MetS was 2.57 kg·kg body weight, whereas in men age ≥ 50 yr the threshold was 2.35 kg·kg body weight.

CONCLUSION

This study is the first to identify a threshold of muscle strength associated with an increased likelihood of MetS in men. Measures of muscle strength may help identify men at risk of chronic disease.

Role of exercise training on autonomic changes and inflammatory profile induced by myocardial infarction

The cardiovascular autonomic imbalance in patients after myocardial infarction (MI) provides a significant increase in mortality rate, and seems to precede metabolic, hormonal, and immunological changes. Moreover, the reduction in the parasympathetic function has been associated with inflammatory response in different pathological conditions. Over the years, most of the studies have indicated the exercise training (ET) as an important nonpharmacological tool in the management of autonomic dysfunction and reduction in inflammatory profile after a myocardial infarction. In this work, we reviewed the effects of ET on autonomic imbalance after MI, and its consequences, particularly, in the post-MI inflammatory profile. Clinical and experimental evidence regarding relationship between alterations in autonomic regulation and local or systemic inflammation response after MI were also discussed.

Physical activity and sedentary behaviour in relation to cardiometabolic risk in children: cross-sectional findings from the Physical Activity and Nutrition in Children (PANIC) Study

Background

Lower levels of physical activity (PA) and sedentary behaviour (SB) have been associated with increased cardiometabolic risk among children. However, little is known about the independent and combined associations of PA and SB as well as different types of these behaviours with cardiometabolic risk in children. We therefore investigated these relationships among children.

Methods

The subjects were a population sample of 468 children 6–8 years of age. PA and SB were assessed by a questionnaire administered by parents and validated by a monitor combining heart rate and accelerometry measurements. We assessed body fat percentage, waist circumference, blood glucose, serum insulin, plasma lipids and lipoproteins and blood pressure and calculated a cardiometabolic risk score using population-specific Z-scores and a formula waist circumference + insulin + glucose + triglycerides - HDL cholesterol + mean of systolic and diastolic blood pressure. We analysed data using multivariate linear regression models.

Results

Total PA was inversely associated with the cardiometabolic risk score (β = -0.135, p = 0.004), body fat percentage (β = -0.155, p < 0.001), insulin (β = -0.099, p = 0.034), triglycerides (β = -0.166, p < 0.001), VLDL triglycerides (β = -0.230, p < 0.001), VLDL cholesterol (β = -0.168, p = 0.001), LDL cholesterol (β = -0.094, p = 0.046) and HDL triglycerides (β = -0.149, p = 0.004) and directly related to HDL cholesterol (β = 0.144, p = 0.002) adjusted for age and gender. Unstructured PA was inversely associated with the cardiometabolic risk score (β = -0.123, p = 0.010), body fat percentage (β = -0.099, p = 0.027), insulin (β = -0.108, p = 0.021), triglycerides (β = -0.144, p = 0.002), VLDL triglycerides (β = -0.233, p < 0.001) and VLDL cholesterol (β = -0.199, p < 0.001) and directly related to HDL cholesterol (β = 0.126, p = 0.008). Watching TV and videos was directly related to the cardiometabolic risk score (β = 0.135, p = 0.003), body fat percentage (β = 0.090, p = 0.039), waist circumference (β = 0.097, p = 0.033) and systolic blood pressure (β = 0.096, p = 0.039). Resting was directly associated with the cardiometabolic risk score (β = 0.092, p = 0.049), triglycerides (β = 0.131, p = 0.005), VLDL triglycerides (β = 0.134, p = 0.009), VLDL cholesterol (β = 0.147, p = 0.004) and LDL cholesterol (β = 0.105, p = 0.023). Other types of PA and SB had less consistent associations with cardiometabolic risk factors.

Conclusions

The results of our study emphasise increasing total and unstructured PA and decreasing watching TV and videos and other sedentary behaviours to reduce cardiometabolic risk among children.

Trial registration

ClinicalTrials.gov Identifier: NCT01803776.

Leisure-time physical activity and the risk of metabolic syndrome: meta-analysis

BACKGROUND

The purpose of this study was to assess the association between leisure-time physical activity (LPA) and the risk of metabolic syndrome (MS).

METHODS

Prospective cohort studies of the association between LPA and the risk of MS were retrieved from the PubMed and Embase databases up to 12 August 2013. The statistical analysis in this study was performed using Stata 11.0 software. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the effect of LPA on the risk of MS.

RESULTS

A total of five articles were included in this meta-analysis. The overall effect sizes indicated that people with moderate level LPA (OR = 0.89, 95% CI: 0.82 to 0.96, P = 0.003) or high level LPA (OR = 0.58, 95% CI: 0.38 to 0.89, P = 0.012) had lower risk of MS than people with low level LPA. The subgroup analysis by gender showed that high level LPA could reduce the risk of MS in populations of different genders (female, OR = 0.20, 95% CI: 0.08 to 0.49, P <0.001; male, OR = 0.59, 95% CI: 0.43 to 0.82, P = 0.002). However, compared with low level LPA, Americans with high level LPA did not significantly reduce the risk of MS (OR = 0.59, 95% CI: 0.43 to 0.82, P = 0.002), while a significant decrease of the risk of MS was found in Europeans with high level LPA (OR = 0.49, 95% CI 0.32 to 0.77, P = 0.002) in the subgroup analysis by region.

CONCLUSIONS

The meta-analysis confirmed that a moderate and high level of LPA could reduce the risk of MS.

Association of Leisure Time Physical Activity and Metabolic Syndrome over 40 Years

BACKGROUND

This study aimed to investigate the relationship between leisure time physical activities (LTPA) and metabolic syndrome (MS).

METHODS

Five thousand seven hundred and thirty two adults 40 years old or older were enrolled in the study from April 2009 to December 2010. National Cholesterol Education Program's Adult Treatment Panel III was used for the criteria of MS, and Minnesota Leisure Time Physical Activity Questionnaire was used to measure LTPA. After adjusted covariates (age, hypertension, smoking, drinking, education level, household income level, work time physical activities, and menopause for females), the relationship between LTPA and MS was analyzed using logistic regression analysis.

RESULTS

The prevalence of MS was 22.8% in men, and 14.1% in women. Average LTPA was 1,498 kcal/wk in men, and 1,308 kcal/wk in women. After adjustment for covariates, the odds ratios of middle and low LTPA compared with high LTPA were 1.06 (0.87-1.34), 1.54 (1.08-1.75), for women, this same association was not seen in men. The prevalence of MS was 22.8% in men and 14.1% in women, and their LTPA burned 1,498 and 1,308 kcal/wk, respectively. When the odds ratio of MS for the high LTPA group was set at 1.0, the odds ratio of MS was 1.06 (0.87-1.34) in the middle LTPA group and 1.54 (1.08-1.75) in the low LTPA group in women, which showed that the MS risk increased when the LTPA was lower. This same association was not seen in men.

CONCLUSION

LTPA was independently associated with metabolic syndrome, but only for women.

An expert fitness diagnosis system based on elastic cloud computing

This paper presents an expert diagnosis system based on cloud computing. It classifies a user's fitness level based on supervised machine learning techniques. This system is able to learn and make customized diagnoses according to the user's physiological data, such as age, gender, and body mass index (BMI). In addition, an elastic algorithm based on Poisson distribution is presented to allocate computation resources dynamically. It predicts the required resources in the future according to the exponential moving average of past observations. The experimental results show that Naïve Bayes is the best classifier with the highest accuracy (90.8%) and that the elastic algorithm is able to capture tightly the trend of requests generated from the Internet and thus assign corresponding computation resources to ensure the quality of service.

Sleep quality and the metabolic syndrome: the role of sleep duration and lifestyle

BACKGROUND

This study examined the association between sleep quality and the metabolic syndrome and whether if it is independent of sleep duration and if it can be explained by lifestyles linked to sleep quality.

METHODS

Cross-sectional study conducted from 2008 to 2010 with 10 342 individuals representative of the population aged ≥18 years in Spain. Poor sleep quality was ascertained through self-reported difficulty falling asleep, difficulty maintaining sleep and sleeping pill consumption. Metabolic syndrome was defined according to the recent harmonized definition. Analyses were conducted with logistic regression and adjusted for the main confounders.

RESULTS

Difficulty falling asleep was associated with higher frequency of metabolic syndrome after adjustment for sociodemographic variables, lifestyle and diagnosed morbidity [odds ratio (OR) = 1.25; 95% confidence interval (CI) = 1.06-1.47]. The association was slightly attenuated after further adjusting for sleep duration (OR = 1.23; 95% CI = 1.04-1.46) and held after additional adjustment for energy intake, adherence to a Mediterranean dietary pattern, energy spent in physical activity and time watching TV (OR = 1.20; 95% CI = 1.01-1.42). No associations were found between metabolic syndrome and other sleep quality indicators. Difficulty falling asleep was associated with high blood pressure in the fully adjusted analyses (OR = 1.17; 95% CI = 1.00-1.37) but not with the rest of components of metabolic syndrome.

CONCLUSIONS

Difficulty falling asleep is associated with metabolic syndrome and, in particular, with high blood pressure. This association is independent of sleep duration and is not due to lifestyles related to poor sleep. This finding should be replicated in prospective studies using objective sleep measures; also, the influence of antihypertensive and lipid-lowering drug treatment on this association should be further studied.

Effects of a Walking Program on Self-management and Risk Factors of Metabolic Syndrome in Older Korean Adults

[Purpose] The aim of this study was to determine the effects of a 12-week walking program on increasing an individual’s self-management and decreasing the risk factors of metabolic syndrome in the older adult population. [Subjects] A total of 31 older adults participated in this study. Eighteen participants in the experimental group and 13 controls completed the pretest and posttest measures. A walking exercise and health education were provided for the experimental group. Data were analyzed by ANCOVAs to examine group differences. [Results] At the end of the 12-week study period, the experimental group showed a significant improvement in individuals’ ability to self-manage their health compared to the control group. Also, there were significant differences between the two groups in the total numbers of risk factors of metabolic syndrome, systolic blood pressure and BMI. No significant difference in blood sugar levels, HDL-C, waist circumference, and triglyceride levels were found between the experimental and control group. [Conclusion] This study revealed that a combination of health education and for walking exercise can lead to improved lifestyle management and reduce risk factors of metabolic syndrome for the elderly population of Korea.

Insulin Sensitivity Following Exercise Interventions: Systematic Review and Meta-Analysis of Outcomes Among Healthy Adults

OBJECTIVE

Although exercise can improve insulin sensitivity, no adequate synthesis exists of exercise intervention studies with regard to their effect on insulin sensitivity. This comprehensive meta-analysis synthesized the insulin sensitivity outcomes of supervised exercise interventions.

METHOD

Extensive literature searching located published and unpublished intervention studies that measured insulin sensitivity outcomes. Eligible studies tested supervised exercise interventions among healthy adults. Primary study characteristics and results were coded. Random-effects meta-analyses of standardized mean differences included moderator analyses.

RESULTS

Data were synthesized across 2509 subjects (115 samples, 78 reports). The overall mean effect size for 2-group postintervention comparisons was 0.38 (95% confidence interval [CI] = 0.25-0.51, I (2) = 0%) and for 2-group pre-post comparisons was 0.43 (95% CI = 0.30-0.56, I (2) = 52%; higher mean insulin sensitivity for treatment than control subjects). The postintervention mean of 0.38 is consistent with treatment subjects ending studies with a mean fasting insulin of 6.8 mU/L if control participants' mean fasting insulin were 7.9 mU/L. Exploratory moderator analyses did not document different insulin sensitivity effect sizes across intervention characteristics or sample attributes.

CONCLUSION

This study documented that exercise is a valuable primary care and community health strategy for healthy adults to improve insulin sensitivity and lower the risk for diabetes conferred by insulin resistance.

A community-based exercise intervention transitions metabolically abnormal obese adults to a metabolically healthy obese phenotype

BACKGROUND

Lower habitual physical activity and poor cardiorespiratory fitness are common features of the metabolically abnormal obese (MAO) phenotype that contribute to increased cardiovascular disease risk. The aims of the present study were to determine 1) whether community-based exercise training transitions MAO adults to metabolically healthy, and 2) whether the odds of transition to metabolically healthy were larger for obese individuals who performed higher volumes of exercise and/or experienced greater increases in fitness.

METHODS AND RESULTS

Metabolic syndrome components were measured in 332 adults (190 women, 142 men) before and after a supervised 14-week community-based exercise program designed to reduce cardiometabolic risk factors. Obese (body mass index ≥30 kg · m(2)) adults with two to four metabolic syndrome components were classified as MAO, whereas those with no or one component were classified as metabolically healthy but obese (MHO). After community exercise, 27/68 (40%) MAO individuals (P<0.05) transitioned to metabolically healthy, increasing the total number of MHO persons by 73% (from 37 to 64). Compared with the lowest quartiles of relative energy expenditure and change in fitness, participants in the highest quartiles were 11.6 (95% confidence interval: 2.1-65.4; P<0.05) and 7.5 (95% confidence interval: 1.5-37.5; P<0.05) times more likely to transition from MAO to MHO, respectively.

CONCLUSION

Community-based exercise transitions MAO adults to metabolically healthy. MAO adults who engaged in higher volumes of exercise and experienced the greatest increase in fitness were significantly more likely to become metabolically healthy. Community exercise may be an effective model for primary prevention of cardiovascular disease.

The neuropathology of sport

The benefits of regular exercise, physical fitness and sports participation on cardiovascular and brain health are undeniable. Physical activity reduces the risk for cardiovascular disease, type 2 diabetes, hypertension, obesity, and stroke, and produces beneficial effects on cholesterol levels, antioxidant systems, inflammation, and vascular function. Exercise also enhances psychological health, reduces age-related loss of brain volume, improves cognition, reduces the risk of developing dementia, and impedes neurodegeneration. Nonetheless, the play of sports is associated with risks, including a risk for mild TBI (mTBI) and, rarely, catastrophic traumatic injury and death. There is also growing awareness that repetitive mTBIs, such as concussion and subconcussion, can occasionally produce persistent cognitive, behavioral, and psychiatric problems as well as lead to the development of a neurodegeneration, chronic traumatic encephalopathy (CTE). In this review, we summarize the beneficial aspects of sports participation on psychological, emotional, physical and cognitive health, and specifically analyze some of the less common adverse neuropathological outcomes, including concussion, second-impact syndrome, juvenile head trauma syndrome, catastrophic sudden death, and CTE. CTE is a latent neurodegeneration clinically associated with behavioral changes, executive dysfunction and cognitive impairments, and pathologically characterized by frontal and temporal lobe atrophy, neuronal and axonal loss, and abnormal deposits of paired helical filament (PHF)-tau and 43 kDa TAR deoxyribonucleic acid (DNA)-binding protein (TDP-43). CTE often occurs as a sole diagnosis, but may be associated with other neurodegenerative disorders, including motor neuron disease (CTE-MND). Although the incidence and prevalence of CTE are not known, CTE has been reported most frequently in American football players and boxers. Other sports associated with CTE include ice hockey, professional wrestling, soccer, rugby, and baseball.

Diagnosis and treatment of polycystic ovary syndrome: an Endocrine Society clinical practice guideline

OBJECTIVE

The aim was to formulate practice guidelines for the diagnosis and treatment of polycystic ovary syndrome (PCOS).

PARTICIPANTS

An Endocrine Society-appointed Task Force of experts, a methodologist, and a medical writer developed the guideline.

EVIDENCE

This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence.

CONSENSUS PROCESS

One group meeting, several conference calls, and e-mail communications enabled consensus. Committees and members of The Endocrine Society and the European Society of Endocrinology reviewed and commented on preliminary drafts of these guidelines. Two systematic reviews were conducted to summarize supporting evidence.

CONCLUSIONS

We suggest using the Rotterdam criteria for diagnosing PCOS (presence of two of the following criteria: androgen excess, ovulatory dysfunction, or polycystic ovaries). Establishing a diagnosis of PCOS is problematic in adolescents and menopausal women. Hyperandrogenism is central to the presentation in adolescents, whereas there is no consistent phenotype in postmenopausal women. Evaluation of women with PCOS should exclude alternate androgen-excess disorders and risk factors for endometrial cancer, mood disorders, obstructive sleep apnea, diabetes, and cardiovascular disease. Hormonal contraceptives are the first-line management for menstrual abnormalities and hirsutism/acne in PCOS. Clomiphene is currently the first-line therapy for infertility; metformin is beneficial for metabolic/glycemic abnormalities and for improving menstrual irregularities, but it has limited or no benefit in treating hirsutism, acne, or infertility. Hormonal contraceptives and metformin are the treatment options in adolescents with PCOS. The role of weight loss in improving PCOS status per se is uncertain, but lifestyle intervention is beneficial in overweight/obese patients for other health benefits. Thiazolidinediones have an unfavorable risk-benefit ratio overall, and statins require further study.

Association between lifting weights and metabolic syndrome among U.S. Adults: 1999-2004 National Health and Nutrition Examination Survey

The purpose of this cross-sectional study was to determine the proportion of U.S. adults who participate in the resistance exercise modality of lifting weights (LWs) by demographic characteristics and to investigate the impact of LWs on the prevalence and risk of metabolic syndrome (MetS) in a national representative sample of U.S. adults. The sample (n = 5,618) in this cross-sectional study included adults aged ≥20 years who participated in the 1999-2004 National Health and Nutrition Examination Survey. Approximately twice as many men (11.2%; 95% confidence interval [CI] 9.5, 13.1) reported LWs as women did (6.3%; 95% CI 5.2, 7.6) with non-Hispanic Whites (9.6%; 95% CI 8.1, 11.4) reporting the highest levels and Mexican Americans reporting the lowest levels (5.6%; 95% CI 4.4, 7.2) of engaging in LWs. Additionally, higher levels of socioeconomic status were associated with greater levels of self-reported LWs. MetS prevalence was found to be significantly lower among U.S. adults reporting LWs (24.6%; 95% CI 19.3, 30.9) compared with adults not reporting LWs (37.3%; 95% CI 35.5, 39.2) with associated risk reductions of 58% (p < 0.001) and 37% (p < 0.01) in the unadjusted model and model adjusted for demographic variables, respectively. These findings suggest that LWs may play a role in reducing the prevalence and risk of MetS among U.S. adults. Therefore, exercise professionals should strongly encourage the activity of LWs among adults of all ages to promote metabolic health and focus programs designed to increase the adoption of LWs among the subgroups who report the lowest levels of LWs.

A lifestyle intervention supported by mobile health technologies to improve the cardiometabolic risk profile of individuals at risk for cardiovascular disease and type 2 diabetes: study rationale and protocol

BACKGROUND

Metabolic syndrome is a cluster of cardiovascular risk factors that greatly increase the risk of developing cardiovascular disease and type 2 diabetes. Regular exercise improves the risk profile, but most people do not successfully change their exercise habits to beneficially reduce risk. Tailored exercise prescribed by a family physician has shown promise as a means to increase fitness and reduce cardiometabolic risk, but optimal implementation practices remain unknown. Mobile health technologies have proved to be a beneficial tool to achieve blood pressure and blood glucose control in patients with diabetes. These technologies may address the limited access to health interventions in rural and remote regions. However, the potential as a tool to support exercise-based prevention activities is not well understood. This study was undertaken to investigate the effects of a tailored exercise prescription alone or supported by mobile health technologies to improve metabolic syndrome and related cardiometabolic risk factors in rural community-dwelling adults at risk for cardiovascular disease and type 2 diabetes.

METHODS/DESIGN

Adults (n = 149) with at least two metabolic syndrome risk factors were recruited from rural communities and randomized to either: 1) an intervention group receiving an exercise prescription and devices for monitoring of risk factors with a smartphone data portal equipped with a mobile health application; or 2) an active control group receiving only an exercise prescription. All participants reported to the research centre at baseline, and at 12-, 24- and 52-week follow-up visits for measurement of anthropometrics and blood pressure and for a blood draw to test blood-borne markers of cardiometabolic health. Vascular and autonomic function were examined. Fitness was assessed and exercise prescribed according to the Step Test and Exercise Prescription protocol.

DISCUSSION

This study tested the effects of a prescriptive exercise intervention alone, versus one supported by mobile health technology on cardiometabolic risk factors. The intervention was designed to be translated into clinical or community-based programming. Results will contribute to the current literature by investigating the utility of mobile health technology support for exercise prescription interventions to improve cardiometabolic risk status and maintain improvements over time; particularly in rural communities.

TRIAL REGISTRATION

CLINICAL TRIALS REGISTRATION

NCT01944124.

Lack of exercise is a major cause of chronic diseases

Chronic diseases are major killers in the modern era. Physical inactivity is a primary cause of most chronic diseases. The initial third of the article considers: activity and prevention definitions; historical evidence showing physical inactivity is detrimental to health and normal organ functional capacities; cause versus treatment; physical activity and inactivity mechanisms differ; gene-environment interaction (including aerobic training adaptations, personalized medicine, and co-twin physical activity); and specificity of adaptations to type of training. Next, physical activity/exercise is examined as primary prevention against 35 chronic conditions [accelerated biological aging/premature death, low cardiorespiratory fitness (VO2max), sarcopenia, metabolic syndrome, obesity, insulin resistance, prediabetes, type 2 diabetes, nonalcoholic fatty liver disease, coronary heart disease, peripheral artery disease, hypertension, stroke, congestive heart failure, endothelial dysfunction, arterial dyslipidemia, hemostasis, deep vein thrombosis, cognitive dysfunction, depression and anxiety, osteoporosis, osteoarthritis, balance, bone fracture/falls, rheumatoid arthritis, colon cancer, breast cancer, endometrial cancer, gestational diabetes, pre-eclampsia, polycystic ovary syndrome, erectile dysfunction, pain, diverticulitis, constipation, and gallbladder diseases]. The article ends with consideration of deterioration of risk factors in longer-term sedentary groups; clinical consequences of inactive childhood/adolescence; and public policy. In summary, the body rapidly maladapts to insufficient physical activity, and if continued, results in substantial decreases in both total and quality years of life. Taken together, conclusive evidence exists that physical inactivity is one important cause of most chronic diseases. In addition, physical activity primarily prevents, or delays, chronic diseases, implying that chronic disease need not be an inevitable outcome during life.

Primary prevention of metabolic syndrome in the community using an evidence-based exercise program

OBJECTIVES

The purpose of the present study was to examine the effectiveness of a community-based exercise program to lower metabolic syndrome (MetS) risk factors.

METHODS

MetS components were retrospectively analyzed in 332 adults (190 women, 142 men) before and after a 14-week supervised community exercise program between January 2007 and May 2012 at the University of Wisconsin-Eau Claire.

RESULTS

Except for total cholesterol, all health outcome variables, including the 5 MetS components, improved following community exercise. Individuals having MetS decreased from 22.3% before participation to 13.5% at end (p<0.05), while prevalence of participants with no MetS components increased 56% (from 65 to 102; p<0.05). Compared to the lowest quartile of relative energy expenditure, participants with the highest quartile were 6.4 (95% CI 1.8-23.2; p<0.05), 7 (95% CI 2.5-20.0; p<0.05) and 9.3 (95% CI 2.6-34.0; p<0.05) times more likely to eliminate low-HDL cholesterol, impaired fasting glucose, and low cardiorespiratory fitness as MetS risk factors, respectively.

CONCLUSION

A community exercise program is an effective method to reduce cardiovascular risk in adults by substantially decreasing the prevalence of MetS and its components. Greater volumes of exercise may increase the likelihood of MetS risk factor elimination.

Leisure-time physical activity and its association with metabolic risk factors in Iranian adults: Tehran Lipid and Glucose Study, 2005-2008

We examined the association between leisure-time physical activity (LTPA) and metabolic syndrome (MetS) among 4,665 randomly selected adults who participated in the Tehran Lipid and Glucose Study, 2005-2008. Normal-weight participants with light LTPA had higher risk of low high-density lipoprotein cholesterol and elevated levels of triglycerides than those with vigorous LTPA. Overweight adults with moderate LTPA had higher risk of having elevated levels of fasting blood glucose than adults with vigorous LTPA and, in the same group, we found an inverse association between light LTPA and MetS after adjustment for sex, age, education levels, smoking, and calorie intake. Although participants in the normal-weight and obese groups with vigorous LTPA had higher risk of high systolic blood pressure than participants with moderate LTPA, this finding had no clinical significance. Increased LTPA is associated with decreased risk of any damaging changes in the markers of MetS.

SenseWear-determined physical activity and sedentary behavior and metabolic syndrome

PURPOSE

The aim of this study was to examine the associations of multiple, objectively measured parameters of physical activity and sedentary behavior with metabolic syndrome (MetS) and its individual components.

METHODS

Physical activity was measured in 370 Flemish adults (age = 41.7 ± 9.8 yr; mean ± SD) for 7 d using a SenseWear Armband. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III guidelines. Logistic regressions examined the associations between the subcomponents of physical activity and sedentary behavior and the odds of having MetS or individual risk factors.

RESULTS

MetS was observed in 10.2% of men and 5.2% of women. Adults who spent ≥60 min·d-1 in moderate-to-vigorous physical activity (MVPA) were 68%-81% less likely to have abdominal obesity, hypertriglyceridemia, and low HDL cholesterol compared with those with <30 min·d MVPA, independent of sex, age, education, smoking, alcohol consumption, and total sedentary time. The total sedentary time and the average duration of a sedentary bout were positively associated with MetS and most of its individual risk factors (odds ratio [OR] = 1.07-1.47). Breaks in sedentary time were inversely associated with abdominal obesity (OR = 0.71, 95% confidence interval [CI] = 0.55-0.91) and hypertriglyceridemia (OR = 0.79, 95% CI 0.63-0.99). These associations were no longer significant after adjustment for MVPA (and total sedentary time). Light physical activity was not associated with MetS or any of the individual risk factors. Time spent in moderate, vigorous, total MVPA, and bouts of MVPA were associated with a reduced likelihood of abdominal obesity (OR = <0.01-0.48), hypertriglyceridemia (OR = 0.14-0.63), and low HDL cholesterol (OR = 0.02-0.43), independent of potential confounders and total sedentary time.

CONCLUSIONS

Engagement in MVPA may be essential to prevent MetS and individual risk factors.

Metabolic syndrome and associated chronic kidney diseases: nutritional interventions

Lifestyle changes such as dietary habits, sedentary life and consumption of energy-dense foods that have occurred over the years has led to an epidemic of abdominal obesity, which in turn resulted in dramatic increase in the prevalence of metabolic syndrome (MetS). Different expert panels have provided various definitions for MetS to enable a clinical diagnosis and treatment of patients at risk of associated complications. Obesity and obesity mediated MetS has been paralleled by escalation in the incidence of chronic kidney disease (CKD). A better understanding of the pathophysiology of MetS and identification of individuals with MetS early in the life course could be important for initiating interventions such as lifestyle modification and dietary restrictions that form the basis for prevention and treatment of MetS and related co-morbidities including CKD. This review is intended to provide a comprehensive summary of the evolution of definition of MetS and association of MetS with CKD. In particular, mechanism of obesity and diabetes mediated CKD and emerging dietary therapies for MetS associated CKD will be discussed.

Concurrent physical activity modifies the association between n3 long-chain fatty acids and cardiometabolic risk in midlife adults

Greater consumption of n3 (ω3) polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) can reduce risk for cardiovascular disease events, yet their effects on metabolic risk factors and diabetes remain unclear. This cross-sectional study used a community volunteer sample to test whether the associations between n3 fatty acids and cardiometabolic risk vary as a function of physical activity. Participants were 344 generally healthy adults, 30-54 y of age, not taking fish oil supplements or confounding medications. Serum phospholipid EPA and DHA were used together (EPA+DHA) as a biomarker of n3 fatty acid exposure. Cardiometabolic risk was calculated as a continuous measure based on standardized distributions of blood pressure, waist circumference, HDL cholesterol, triglycerides, glucose, and a simple count of risk factors. Insulin resistance was estimated from the homeostatic model assessment. Physical activity was found to predict cardiometabolic risk (P ≤ 0.02) and insulin resistance (P ≤ 0.02) and to moderate the association between EPA+DHA and both cardiometabolic risk (P-interaction ≤ 0.02) and insulin resistance (P-interaction ≤ 0.02). Specifically, higher EPA+DHA was associated with lower cardiometabolic risk and insulin resistance in persons engaged in regular physical activity but not in relatively inactive individuals. These findings were noted in several components of cardiometabolic risk, in men and women separately, and in models adjusted for overall diet quality. In midlife adults, habitual physical activity may be necessary to unmask the salutary effects of n3 fatty acids on cardiometabolic risk and insulin resistance.

Exercise after diagnosis and metabolic syndrome among breast cancer survivors: a report from the Shanghai Breast Cancer Survival Study

Metabolic syndrome (MetS) is an established risk factor for cardiovascular diseases and mortality. Limited data are available on the prevalence of MetS and its association with exercise among breast cancer survivors. The present study included 1,696 breast cancer survivors from the Shanghai Breast Cancer Survival Study, a population-based prospective cohort study conducted between April 2002 and October 2011 in Shanghai, China. All women had a physical examination taken at study clinic approximately 60 months post-diagnosis. Exercise was assessed at approximately 6, 18, 36, and 60 months post-diagnosis. Information on medical history, tumor characteristics, cancer treatment, anthropometrics, and lifestyle was collected at study enrollment. Associations between exercise and MetS at 60 months post-diagnosis were evaluated with multivariable logistic regression models. The mean age of the study population was 56.68 at 60-month survey, and the mean follow-up since cancer diagnosis was 63.66 months. The prevalence of MetS using National Cholesterol Education Program Adult Treatment Panel III criteria at approximately 60 months after diagnosis was 33.14%. Among overweight and obesity breast cancer survivors (body mass index (BMI) ≥ 25 kg/m(2) at baseline), the prevalence was 55.18%. The most common type of exercise in this population was walking (45.40%) at baseline. Exercise participation between 6 and 60 months post-diagnosis was inversely associated with the prevalence of MetS with the adjusted odds ratio (OR) for exercise participation of ≥ 3.5 h/week (30 min/day) being 0.69 (95% confidence interval (CI) 0.48-0.98). In addition consistent exercise participation reduced the prevalence of MetS (adjusted OR 0.70 (95% CI 0.50-1.00). Associations of exercise with MetS were not modified by baseline waist circumference, BMI, comorbidity, baseline menopausal status, TNM stage, cancer treatment, or ER/PR status (p interactions > 0.05). Regular and persistent exercise after cancer diagnosis, even at low-to-moderate intensity level, decreases the prevalence of MetS among long-term breast cancer survivors.

Is the frequency of weekly moderate-to-vigorous physical activity associated with the metabolic syndrome in Canadian adults?

Previous physical activity guidelines recommended that adults be active on most or all days of the week. Current guidelines recommend accumulating ≥150 min/week of moderate-to-vigorous physical activity (MVPA), with no recommendation for frequency. This study examined the association between the frequency of physical activity throughout the week and the metabolic syndrome (MetS) in physically active adults. This cross-sectional study included 2324 adults aged 18-64 years from the 2007-2011 cycles of the nationally representative Canadian Health Measures Survey. MVPA was measured over 7 days using Actical accelerometers. Physically active participants (≥150 min/week of MVPA) were assigned to frequently active (≥5 days/week with ≥30 min of MVPA) and infrequently active (1-4 days/week with ≥30 min of MVPA) groups. Associations were examined using logistic regression controlling for age, sex, and education. The relative odds of the MetS was 4.43 (95% confidence interval: 2.26-8.69) times higher in physically inactive participants than physically active participants. Within physically active participants, the relative odds of the MetS was 1.73 (0.87-3.41) times higher in the infrequently active group than the frequently active group. However, this was not a significant difference (p = 0.11), and after adjustment for total weekly MVPA, the relative odds of the MetS in the infrequently active group was reduced to 0.85 (0.42-1.72). The frequency of physical activity throughout the week was not independently associated with the MetS among active adults. Conversely, the weekly volume of MVPA was strongly associated with the MetS.

The metabolic syndrome and its components in postmenopausal women

BACKGROUND

Prevalence of the metabolic syndrome (METS) increases significantly after the menopause.

OBJECTIVE

To assess the prevalence of the METS and its components in postmenopausal women. Factors relating to each of the composing items of the METS were also analyzed.

METHODS

Natural postmenopausal women (40-65 years) were invited to participate in this cross-sectional study in order to assess the presence of the METS using modified Adult Treatment Panel III (ATP-III) criteria. Participants were also requested to fill out a general socio-demographic questionnaire.

RESULTS

A total of 204 women were surveyed with a median age of 56 years. A 52.9% presented the METS according to modified ATP-III criteria, with 37.3% presenting hyperglycemia, 51.5% hypertension, 58.3% abdominal obesity, 45.6% high triglyceride levels and 56.4% low HDL-C levels. Women with the METS presented a higher rate of dyslipidemia (high triglyceride and low HDL-C levels), hyperglycemia, hypertension and abdominal obesity than those without the syndrome. Those with abdominal obesity and hyperglycemia significantly displayed higher rates of low HDL-C levels (bivariate analysis). Multiple linear regression analysis found a positive correlation between glucose and triglyceride levels. Systolic blood pressure significantly and positively correlated to age and abdominal circumference. Abdominal circumference displayed an inverse correlation with educational level.

CONCLUSION

Prevalence of the METS in this postmenopausal female sample was high and associated to metabolic and lipid derangements. As abdominal obesity was significantly associated to lower education, there is an urgent need of implementing educational programs directed to high-risk populations in order to increase awareness of the problem.

Low levels of physical activity are associated with increased metabolic syndrome risk factors in korean adults

BACKGROUND

Low levels of physical activity (PA) are strongly associated with the development of metabolic syndrome (MetS) and chronic diseases. However, few studies have examined this association in Koreans. The primary purpose of this study was to examine the associations between PA and MetS risks in Korean adults.

METHODS

A total of 1,016 Korean adults (494 males and 522 females) participated in this study. PA levels were assessed using the International PA Questionnaire. MetS risk factors were determined using clinically established diagnostic criteria.

RESULTS

Compared with the highest PA group, the group with the lowest level of PA was at greater risk of high triglyceride (TG) in males (odds ratio [OR], 1.87; 95% confidence interval [CI], 1.07 to 3.24) and of hemoglobin A1c ≥5.5% in females (OR, 1.75; 95% CI, 1.00 to 3.04) after adjusting for age and body mass index. Compared with subjects who met the PA guidelines, those who did not meet the guidelines were more likely to have low high density lipoprotein cholesterol in both males (OR, 1.69; 95% CI, 1.11 to 2.58), and females (OR, 1.82; 95% CI, 1.20 to 2.77). Furthermore, those who did not meet the PA guidelines were at increased risk of high TG levels in males (OR, 1.69; 95% CI, 1.23 to 2.86) and abnormal fasting glucose (OR, 1.93; 95% CI, 1.17 to 3.20) and MetS (OR, 2.10; 95% CI, 1.15 to 3.84) in females.

CONCLUSION

Increased levels of PA are significantly associated with a decreased risk of abnormal MetS components.

Objectively measured light-intensity lifestyle activity and sedentary time are independently associated with metabolic syndrome: a cross-sectional study of Japanese adults

BACKGROUND

Reducing sedentary time and increasing lifestyle activities, including light-intensity activity, may be an option to help prevent metabolic syndrome (MetS). The purpose of the present study was to examine whether objectively measured light-intensity lifestyle activity and sedentary time is associated with MetS, independent of moderate-vigorous intensity physical activity (MVPA).

METHODS

The participants in this cross-sectional study were 483 middle-aged Japanese adults, aged 30-64 years. The participants were divided into those with or without MetS according to the Japanese criteria for MetS. A triaxial accelerometer was used to measure light-intensity lifestyle activity [1.6-2.9 metabolic equivalents (METs)] and sedentary time (≤1.5 METs). Logistic regression was used to predict MetS from the levels of light-intensity lifestyle activity and sedentary time with age, sex, smoking, calorie intake, accelerometer wear time, and MVPA as covariates.

RESULTS

The odds ratios (OR) for MetS in the highest and middle tertiles of light-intensity lifestyle activity were 0.44 [95% confidence interval (CI): 0.24 to 0.81] and 0.51 (95% CI: 0.29 to 0.89) relative to the lowest tertile, after adjustment for age, sex, smoking, calorie intake, accelerometer wear time and MVPA (Ptrend = 0.012). Sedentary time was also associated with the risk of MetS (Ptrend = 0.018). Among participants in the highest tertile of sedentary time, the risk of MetS was 2.27-times greater than that in the lowest tertile (95% CI: 1.25 to 4.11). The risk of MetS was not significantly increased in subjects in the middle tertile of sedentary time.

CONCLUSIONS

We found that light-intensity lifestyle activity and sedentary time were significantly associated with the risk of MetS, independent of MVPA. The results of our study suggest that public health messages and guidelines should be refined to include increases in light-intensity lifestyle activity and/or decreases in sedentary time, alongside promoting MVPA, to prevent MetS.

Does Regular Exercise without Weight Loss Reduce Insulin Resistance in Children and Adolescents?

Despite considerable efforts to tackle childhood obesity, it is recognized as one of the biggest health problems globally. Childhood obesity is a leading cause of many comorbid conditions such as metabolic syndrome and insulin resistance as well as type 2 diabetes. A strong body of evidence suggests that regular exercise without calorie restriction or weight loss is associated with reduced insulin resistance as well as improved insulin sensitivity in overweight and obese adults. However, despite the well-known benefits associated with regular exercise alone, the independent role of exercise training without calorie restriction on insulin resistance is still uncertain in youth. Some studies observed that both the aerobic and resistance type of exercise training without calorie restriction resulted in meaningful changes in insulin sensitivity, suggesting that exercise alone is an effective therapeutic strategy for reducing insulin resistance in overweight and obese youth. However, only few studies are available on the optimal dose of exercise training without calorie restriction or preferred exercise modality for reducing insulin resistance, which warrants further investigations in the pediatric population.

Physical fitness in children infected with the human immunodeficiency virus: associations with highly active antiretroviral therapy

Obesity, sedentary lifestyles, and antiretroviral therapies may predispose HIV-infected children to poor physical fitness. Estimated peak oxygen consumption (VO(2) peak), maximal strength and endurance, and flexibility were measured in HIV-infected and uninfected children. Among HIV-infected children, anthropometric and HIV disease-specific factors were evaluated to determine their association with VO(2) peak. Forty-five HIV-infected children (mean age 16.1 years) and 36 uninfected children (mean age 13.5 years) participated in the study. In HIV-infected subjects, median viral load was 980 copies/ml (IQR 200-11,000 copies/ml), CD4% was 28% (IQR 15-35%), and 82% were on highly active antiretroviral therapy (HAART). Compared to uninfected children, after adjusting for age, sex, race, body fat, and siblingship, HIV-infected children had lower VO(2) peak (25.92 vs. 30.90 ml/kg/min, p<0.0001), flexibility (23.71% vs. 46.09%, p=0.0003), and lower-extremity strength-to-weight ratio (0.79 vs. 1.10 kg lifted/kg of body weight, p=0.002). Among the HIV-infected children, a multivariable analysis adjusting for age, sex, race, percent body fat, and viral load showed VO(2) peak was 0.30 ml/kg/min lower per unit increase in percent body fat (p<0.0001) and VO(2) peak (SE) decreased 29.45 (± 1 .62), 28.70 (± 1.87), and 24.09 (± 0.75) ml/kg/min across HAART exposure categories of no exposure, <60, and ≥ 60 months, respectively (p<0.0001). HIV-infected children had, in general, lower measures of fitness compared to uninfected children. Factors negatively associated with VO(2) peak in HIV-infected children include higher body fat and duration of HAART ≥ 60 months. Future studies that elucidate the understanding of these differences and mechanisms of decreased physical fitness should be pursued.

Frailty in older inpatients: what physicians need to know

Physicians involved in the care of medical inpatients, irrespective of their sub-specialty area, will be responsible for the management of a significant number of older adults with complex care needs and multiple co-morbidities. These patients are vulnerable to poor outcomes (including falls, institutionalization and death)--a vulnerability often linked with the term 'frail' or 'frailty'. Frailty is associated with advanced chronological age and chronic disease but is a separate construct. The measurement of frailty has received significant attention in recent geriatric medicine literature, with various models proposed to predict the risk of poor outcomes. Here, we briefly review different approaches to the definition of frailty, focusing on the conceptualization of frailty as the failure of a complex system. We explore how falls, a common cause of morbidity and mortality in older patient groups, may be a manifestation of increasing frailty and argue that falls services should avoid the practice of pursuing a single-organ cause when there are likely to be several contributing factors at play. We also consider the impact of frailty on medication prescribing and discuss how individualized prescribing could reduce the risk of adverse drug reactions in at-risk older inpatients. While it can be frustrating for physicians to manage patients who do not fit well into disease-based diagnostic and management algorithms, understanding frailty has the potential to improve the clinical care of vulnerable older people in the hospital setting.

Intensity versus duration of physical activity: implications for the metabolic syndrome. A prospective cohort study

OBJECTIVES

To explore the relative importance of leisure time physical activity (LTPA), walking and jogging on risk of developing the metabolic syndrome (MS).

DESIGN

A prospective cohort study.

SETTING

The Copenhagen City Heart Study.

PARTICIPANTS

10 135 men and women aged 21-98 years who attended an initial examination in 1991-1994 and were re-examined after 10 years.

OUTCOME MEASURES

The association of LTPA, jogging, walking speed and walking volume with MS at baseline and at 10-year follow-up was investigated by multiple logistic regression analyses.

RESULTS

Baseline prevalence of MS was 20.7% in women and 27.3% in men. In both women and men, MS prevalence was associated with lower LTPA and walking speed and was lower in joggers compared to non-joggers. In subjects free of MS at baseline, 15.4% had developed MS at 10-year follow-up. Risk of developing MS was reduced in subjects with moderate or high LTPA, higher walking speed and in joggers whereas a higher volume of walking was not associated with reduced risk. After multiple adjustment, odds ratio (OR) of developing MS in moderate/high LTPA was 0.71 (95% CI 0.50 to 1.01), fast walking speed 0.51 (0.33 to 0.80) and joggers 0.60 (0.37 to 0.95) and walking >1 h daily 1.22 (0.91 to 1.65).

CONCLUSIONS

Our results confirm the role of physical activity in reducing MS risk and suggest that intensity more than volume of physical activity is important.

Validation of Web-based physical activity measurement systems using doubly labeled water

BACKGROUND

Online or Web-based measurement systems have been proposed as convenient methods for collecting physical activity data. We developed two Web-based physical activity systems-the 24-hour Physical Activity Record Web (24hPAR WEB) and 7 days Recall Web (7daysRecall WEB).

OBJECTIVE

To examine the validity of two Web-based physical activity measurement systems using the doubly labeled water (DLW) method.

METHODS

We assessed the validity of the 24hPAR WEB and 7daysRecall WEB in 20 individuals, aged 25 to 61 years. The order of email distribution and subsequent completion of the two Web-based measurements systems was randomized. Each measurement tool was used for a week. The participants' activity energy expenditure (AEE) and total energy expenditure (TEE) were assessed over each week using the DLW method and compared with the respective energy expenditures estimated using the Web-based systems.

RESULTS

The mean AEE was 3.90 (SD 1.43) MJ estimated using the 24hPAR WEB and 3.67 (SD 1.48) MJ measured by the DLW method. The Pearson correlation for AEE between the two methods was r = .679 (P < .001). The Bland-Altman 95% limits of agreement ranged from -2.10 to 2.57 MJ between the two methods. The Pearson correlation for TEE between the two methods was r = .874 (P < .001). The mean AEE was 4.29 (SD 1.94) MJ using the 7daysRecall WEB and 3.80 (SD 1.36) MJ by the DLW method. The Pearson correlation for AEE between the two methods was r = .144 (P = .54). The Bland-Altman 95% limits of agreement ranged from -3.83 to 4.81 MJ between the two methods. The Pearson correlation for TEE between the two methods was r = .590 (P = .006). The average input times using terminal devices were 8 minutes and 10 seconds for the 24hPAR WEB and 6 minutes and 38 seconds for the 7daysRecall WEB.

CONCLUSIONS

Both Web-based systems were found to be effective methods for collecting physical activity data and are appropriate for use in epidemiological studies. Because the measurement accuracy of the 24hPAR WEB was moderate to high, it could be suitable for evaluating the effect of interventions on individuals as well as for examining physical activity behavior.