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Effects of exercise therapy on bone mineral density in early postmenopausal women: a controlled trial

Shilin DENG MD ,

《医学前沿（英文）》 2009年第3卷第3期页码 323-329 doi: 10.1007/s11684-009-0061-2

摘要： The purpose of this article is to determine the effect of a well-designed combined aerobic, resistance, and extension exercise program on bone mineral density (BMD) in postmenopausal women. The population comprised 45 postmenopausal women, who exercised over 12months (exercise group), and 36 women who served as a non-training control group. BMD of the hip, and lumbar spine was measured at the baseline and 12th month. Repeated measurement analysis of variance and nonparametric test were utilized to compare differences between the exercise group and controls. Thirty-six out of 45 persons in the exercise group and 36 controls completed the study. Average compliance was 82.2% for the whole exercise group at the 12th month. All the subjects had decreased BMD, but the rate of bone loss was lower in the exercise group than in the control group at the L4 and hip. Although the exercise program in this study may probably reduce the rate of bone loss in weight-bearing skeletal sites, we do not suggest the exercise by itself be viewed as prevention or treatment for osteoporosis. Further, the exact dose-response relationship of exercise and bone mass in early postmenopause is not clear.

关键词： early postmenopausal women bone mineral density exercise effects

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Role of exercise training on insulin resistance and TNF-α in high-fat diet rats

Hui SUN MD, Xiuling DENG MM, Fangxi XIAO MD, Lulu CHEN MD, Huiqing LI MD,

《医学前沿（英文）》 2009年第3卷第4期页码 403-407 doi: 10.1007/s11684-009-0071-0

摘要： This study investigated the effect of exercise training on insulin resistance and serum and adipose TNF-α in high-fat diet-induced insulin-resistant rats. Thirty male Wistar rats were randomly divided into two groups: normal control group (NC; =8) that accepted normal chow and high-fat diet group (HF; =22) that fed on high-fat diet to induce insulin resistance model. The HF group was randomly assigned to two subgroups after 18 weeks: sedentary group (SE; =10) and exercise training group (ET; =12) that performed swimming exercise training for 6 weeks, while both groups continued high-fat diet. Changes of body weight, lipid profile, and fasting plasma glucose and insulin were measured. The insulin sensitivity index (ISI) was calculated. Serum concentration of TNF-α was detected by ELISA. The expression of TNF-α mRNA and protein in adipose tissue was examined by using real-time fluorescence quantitative polymerase chain reaction (PCR) and Western blot, respectively. After 18 weeks, compared with the NC group, body weight, blood lipid, glucose, and insulin in the HF group were significantly elevated, while the ISI decreased obviously, which suggested that insulin resistance appeared in the HF group. After exercise training for 6 weeks, compared with the SE group, both ISI and serum TNF-α concentration in the ET group were decreased significantly; however, the expression levels of TNF-α mRNA and protein in adipose tissue increased by 27.5% and 20.5%, respectively. In conclusion, exercise training ameliorates insulin resistance. The reduction of the level of serum TNF-α and the increased expression of TNF-α in adipose tissue by exercise training may be involved in this mechanism.

关键词： exercise training insulin resistance tumor necrosis factor-α

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Low-carbohydrate diets lead to greater weight loss and better glucose homeostasis than exercise: a randomized

《医学前沿（英文）》 2021年第15卷第3期页码 460-471 doi: 10.1007/s11684-021-0861-6

摘要： Lifestyle interventions, including dietary adjustments and exercise, are important for obesity management. This study enrolled adults with overweight or obesity to explore whether either low-carbohydrate diet (LCD) or exercise is more effective in metabolism improvement. Forty-five eligible subjects were randomly divided into an LCD group (n=22) and an exercise group (EX, n=23). The subjects either adopted LCD (carbohydrate intake<50 g/day) or performed moderate-to-vigorous exercise (≥30 min/day) for 3 weeks. After the interventions, LCD led to a larger weight loss than EX (−3.56±0.37 kg vs. −1.24±0.39 kg, P<0.001), as well as a larger reduction in fat mass (−2.10±0.18 kg vs. −1.25±0.24 kg, P=0.007) and waist circumference (−5.25±0.52 cm vs. −3.45±0.38 cm, P=0.008). Both interventions reduced visceral and subcutaneous fat and improved liver steatosis and insulin resistance. Triglycerides decreased in both two groups, whereas low-density lipoprotein cholesterol increased in the LCD group but decreased in the EX group. Various glycemic parameters, including serum glycated albumin, mean sensor glucose, coefficient of variability (CV), and largest amplitude of glycemic excursions, substantially declined in the LCD group. Only CV slightly decreased after exercise. This pilot study suggested that the effects of LCD and exercise are similar in alleviating liver steatosis and insulin resistance. Compared with exercise, LCD might be more efficient for weight loss and glucose homeostasis in people with obesity.

关键词： low-carbohydrate diet obesity nonalcoholic fatty liver disease continuous glucose monitoring mean sensor glucose

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Phenomena identification and ranking table exercise for thorium based molten salt reactor-solid fuel

Xiaojing LIU, Qi WANG, Zhaozhong HE, Kun CHEN, Xu CHENG

《能源前沿（英文）》 2019年第13卷第4期页码 707-714 doi: 10.1007/s11708-019-0616-0

摘要： Thorium based molten salt reactor-solid fuel (TMSR-SF) design is an innovative reactor concept that uses high-temperature tristructural-isotropic (TRISO) fuel with a low-pressure liquid salt coolant. In anticipation of getting licensed applications for TMSR-SF in the future, it is necessary to fully understand the significant features and phenomena of TMSR-SF design, as well as its transient behavior during accidents. In this paper, the safety-relevant phenomena, importance, and knowledge base were assessed for the selected events and the transient of TMSR-SF during station blackout scenario is simulated based on RELAP/SCDAPSIM Mod 4.0. The phenomena having significant impact but with limited knowledge of their history are core coolant bypass flows, outlet plenum flow distribution, and intermediate heat exchanger (IHX) over/under cooling transients. Some thermal hydraulic parameters during the station blackout scenario are also discussed.

关键词： phenomena identification and ranking table (PIRT) thorium based molten salt reactor-solid fuel (TMSR-SF) safety analysis RELAP/SCDAPSIM

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Design and preliminary evaluation of an exoskeleton for upper limb resistance training

Tzong-Ming WU, Dar-Zen CHEN

《机械工程前沿（英文）》 2012年第7卷第2期页码 188-198 doi: 10.1007/s11465-012-0327-2

摘要：

Resistance training is a popular form of exercise recommended by national health organizations, such as the American College of Sports Medicine (ACSM) and the American Heart Association (AHA). This form of training is available for most populations. A compact design of upper limb exoskeleton mechanism for home-based resistance training using a spring-loaded upper limb exoskeleton with a three degree-of-freedom shoulder joint and a one degree-of-freedom elbow joint allows a patient or a healthy individual to move the upper limb with multiple joints in different planes. It can continuously increase the resistance by adjusting the spring length to train additional muscle groups and reduce the number of potential injuries to upper limb joints caused by the mass moment of inertia of the training equipment. The aim of this research is to perform a preliminary evaluation of the designed function by adopting an appropriate motion analysis system and experimental design to verify our prototype of the exoskeleton and determine the optimal configuration of the spring-loaded upper limb exoskeleton.

关键词： exoskeleton free-weight exercise upper limb motion analysis

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Joint association of physical activity/screen time and diet on CVD risk factors in 10-year-old children

null

《医学前沿（英文）》 2012年第6卷第4期页码 428-435 doi: 10.1007/s11684-012-0232-4

摘要：

The increasing prevalence of childhood overweight and obesity has been associated with an increased risk for cardiovascular disease (CVD). While several studies examined the effect of single behaviors such as physical activity (PA), sedentary behavior or diet on CVD risk, there is a lack of research on combined associations, specifically in children. Therefore, the purpose of this study was to examine the joint association of PA or screen time (ST) and diet on CVD risk factors in children. PA, ST and diet were assessed via questionnaire in 210 fifth grade students (age: 10.6±0.4 years). The healthy eating index (HEI) was subsequently calculated as indicator for diet quality. Height, weight, % body fat, and resting blood pressure were measured according to standard procedures and blood samples obtained via fingerprick were assayed for blood lipids. Total cholesterol HDL ratio (TC:HDL), mean arterial pressure (MAP), and % body fat were used as indicators of CVD risk. 55% of children did not meet current PA recommendations on at least 5 days/week and 70% exceeded current recommendations for ST. Further, only 2.5% possessed a “good” diet (HEI>80). There was no significant association of PA or ST and diet on CVD risk score. Neither TC:HDL, MAP, and % body fat nor the total CVD risk score was significantly correlated with diet, PA, or ST. Children in the high PA group, however, had significantly better diet scores. Despite the fact that self-reported PA, ST, or dietary intake were not directly related to CVD risk in this sample, higher activity levels were associated with a healthier diet and lower ST indicating an overall healthier lifestyle of this subgroup.

关键词： exercise sedentary behavior metabolic syndrome health behavior adolescents TV time healthy eating index