Metabolic response to 6-week aerobic exercise training and dieting in previously sedentary overweight and obese pre-menopausal women:A randomized trial

Background： The aim of this study was to compare 6 weeks short-term moderate intensity aerobic exercise and dieting on serum metabolomics and cardio-metabolic risk factors in pre-menopausal women. Methods： Ninety previously inactive overweight and obese （BMI 25-35 kg/m2） women （age 41.5 ± 7.6 years） were randomized to either a 6-week Nordic walking exercise program （EX, n = 45） or dietary counseling group （DI, n = 45）. Body composition, serum glucose, insulin and lipids were measured. Serum low-molecular-weight metabolites and lipid constituents were analyzed by nuclear magnetic resonance spectroscopy. Measurements were done at baseline and 7 days after the last training session. Results： Six weeks aerobic exercise program yielded reductions in serum free fatty acids （-34.7%, 95% confidence interval （CI）, -50 to -18, p 〈 0.001）, glucose （-9.6%, 95%CI, -15 to -4, p 〈 0.001） and homeostasis model assessment of insulin resistance （HOMA-IR） （-28.7%, 95%CI, -48 to -10, p = 0.005） without changes in body weight or fat mass. Diet counseling resulted in loss of body weight （1.5%, 95%CI, -2.3 to -0.7, p = 0.001） but no changes in free fatty acids, fasting glucose, or HOMA-IR were found. Conclusion： Our results indicate that small weight loss does not produce measurable health benefits, whereas short-term regular aerobic exercise can improve glucose and lipid metabolism even in the absence of weight loss in previously sedentary overweight and obese women.

The role of physical activity and exercise in obesity and weight management: Time for critical appraisal

The prevalence of overweight and obesity has increased dramatically during last 3 decades with devastating consequences to public health. Recommended strategies to reduce obesity have focused on healthier diet and physical activity （PA）. Clearly, these approaches have not been successful, but whether this is due to failure to restrict energy intake or to maintain high levels of energy expenditure has been the subject of great controversy. Consequently, there has been a great deal of confusion about the role of PA and exercise in obesity and weight management. In this article, the theoretical basis for considering reduced PA and energy expenditure as the cause of obesity is appraised. Further, the role of PA in food intake and weight control is examined. The idea that obesity is caused by consistent deeline in daily energy expenditure is not supported either by objective measures of energy expenditure or physiological theory of weight gain alone. However, since voluntary exercise is the most important discretionary component of total daily energy expenditure, it can affect energy balance. Therefore, PA and exercise hold potential as part of the solution for the ongoing obesity epidemic.

Effect of aerobic exercise on insulin resistance and centra1 adiposity disappeared after the discontinuation of intervention in overweight women

Purpose： This study aimed to assess whether the benefits of exercise on central adiposity and insulin resistance （HOMA-IR） are maintained after discontinuation of intervention in the overweight/obese （OWOB） women. Methods： The study subjects were from 2 independent studies with similar aerobic exercise （AE） intervention programs. In study I, I50WOB postmenopausal women with pre-diabetes （body mass index, BMI = 24-33 kg/m2, aged 52-65 years） completed an 8-month exercise intervention and were followed for 2 years after the intervention. In study lI, 12 OWOB （BM1 = 25-35 kg/m2, aged 30-50 years） premenopausal women participated in a 6-week AE and were followed for 4 years after the intervention. The exercise program consisted of progressive AE with intensity of 60%-75% of initial fitness level, 30-60 min/time and 3-5 times/week. Fat mass （FM） was assessed by Dual Energy X-ray Absorptiometry （DXA Prodigy; study I） or bioelectrical impedance device （Inbody 720; study II）. Plasma glucose and insulin were assessed by chemiluminescent immunoassay and HOMA-IR was calculated. Results： Both 8-month and 6-week moderate AE were effective in reducing HOMA-IR （-18.9%, p = 0.012 and -26.7%, p = 0.046, respectively）, and 8-month AE reduced FM at upper abdominal region （-6.2%, p = 0.021）. However, these improvements were not maintained in either study at the follow-up. Conclusion： The AE program used in these studies was effective to reduce insulin resistance and/or FM in central body region among overweight and obese women. However, when exercise intervention was discontinued, the beneficial effects following both short- and long-term intervention disappeared. Thus maintaining exercise seems to be required if one wants to reap the benefits of exercise in the long-term.

Comparison of heart rate monitoring with indirect calorimetry for energy expenditure evaluation

Purpose:The purpose of this study was to compare established methods with newly-developed methods for estimating the total energy expenditure(TEE). Methods:The study subjects comprised 46 individuals,including 16 middle-aged men(mean age 51.4 years),14 middle-aged women(mean age 49.9 years) and 16 young women(mean age 19.1 years).The TEE was estimated from 24-h heart rate(HR) data using newly-developed software (MoveSense HRAnalyzer 201 la,RC1.Suunto Oy,Vantaa,Finland),and was compared against the TEE determined using doubly labeled water (DLW).Agreement between the two methods was analyzed using Bland and Altman plots. Results:The HR method yielded similar TEE values as the DLW method at the group level,with an average of 8.6 kcal/day in the difference in the mean,but with large individual variations.Forty-four(96%) out of 46 subjects fell within±2SD of the mean difference in TEE comparisons, and there was no tendency towards under- or over-estimation. Conclusion:Our results indicate that the current software using HR analysis for the estimation of daily TEE needs further development for use with free-living individuals.

Exercise,the endocannabinoid system and metabolic health

1.The endocannabinoid system in obesity and metabolic disorders As obesity and associated metabolic disorders,such as type 2 diabetes and dyslipidemia,are becoming one of the most serious health problems worldwide,development of effective therapies is a high priority.In the search for treatments,the recently discovered endocannabinoid system(ECS) has begun to garner attention,and a wealth of research is now

Effects of exercise and dietary interventions on serum metabolites in men with insomnia symptoms:A 6-month randomized controlled trial

Accumulating evidence show that exercise and diet interventions are associated with improved sleep quality.Studies investigating the effects of exercise and dieting on circulating metabolomics in people with sleep disorders,particularly insomnia,are scarce.This 6-month randomized study aimed to assess the effects of exercise and dietary interventions on serum metabolites in men with insomnia symptoms.Seventy-two Finnish men(age:51.6±10.1 years)with chronic insomnia symptoms who were assigned to different intervention groups completed this study(exercise,n=24;diet,n=27;and control,n=21).The Shapiro-Wilk W-test,Levene test,Spearman correlation analysis,and analysis of variance were used for data analysis.We found that exercise and diet intervention were associated with improved sleep quality and with a number of metabolites across different biochemical pathways.Although we could not show causality,our findings provide new insight into the biological mechanisms underlying the health effects of physical activity,diet,and sleep quality.Further investigation is needed to better understand the link among lifestyle,sleep quality,and metabolic health.