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51.
Background:Osteoarthritis is one of the leading causes of pain and disability worldwide,and a large percentage of patients with osteoarthritis are individuals who are also obese.In recent years,a series of animal models have demonstrated that obesity-inducing diets can result in synovial joint damage(both with and without the superimposition of trauma),which may be related to changes in percentage of body fat and a series of low-level systemic inflammatory mediators.Of note,there is a disparity between whether the dietary challenges commence at weaning,representing a weanling onset,or at skeletal maturity,representing an adult onset of obesity.We wished to evaluate the effect ofthe dietary exposure time and the age at which animals are exposed to a high-fat and high-sucrose(HFS) diet to determine whether these factors may result in disparate outcomes,as there is evidence suggesting that these factors result in differential metabolic disturbances.Based on dietary exposure time,we hypothesized that rats fed an HFS diet for 14 weeks from weaning(HFS Weanling) would demonstrate an increase in knee joint damage scores,whereas rats exposed to the HFS diet for 4 weeks,starting at 12 weeks of age(HFS Adult) and rats exposed to a standard chow diet(Chow)would not display an increase in knee joint damage scores.Methods:Male Sprague-Dawley rats were fed either an HFS diet for 14 weeks from weaning(HFS Weanling) or an HFS diet for 4 weeks,starting at 12 weeks of age(HFS Adult).At sacrifice,joints were scored using the modified Mankin Criteria,and serum was analyzed for a defined subset of inflammatory markers(Interleukin-6,leptin,monocyte chemoattractant protein-1,and tumor necrosis factorα).Results:When the HFS Weanling and HFS Adult groups were compared,both groups had a similar percent of body fat,although the HFS Weanling group had a significantly greater body mass than the HFS Adult group.The HFS Weanling and HFS Adult animals had a significant increase in body mass and percentage of body fat when compared to the Chow group.Although knee joint damage scores were low in all 3 groups,we found,contrary to our hypothesis,that the HFS Adult group had statistically significant greater knee joint damage scores than the Chow and HFS Weanling groups.Furthermore,we observed that the HFS Weanling group did not have significant differences in knee joint damage scores relative to the Chow group.Conclusion:These findings indicate that the HFS Weanling animals were better able to cope with the dietary challenge of an HFS diet than the HFS Adult group.Interestingly,when assessing various serum proinflammatory markers,no significant differences were detected between the HTS Adult and HFS Weanling groups.Although details regarding the mechanisms underlying an increase in knee joint damage scores in the HFS Adult group remain to be elucidated,these findings indicate that dietary exposure time maybe less important than the age at which an HFS diet is introduced.Moreover,increases in serum proinflammatory mediators do not appear to be directly linked to knee joint damage scores in the HFS Weanling group animals but may be partially responsible for the observed knee joint damage in the adults over the very short time of exposure to the HFS diet.  相似文献   
52.
This study examined the relationship between sit-to-stand (STS) power and physical function in adults with severe obesity. Thirty-eight adults (age: 44 ± 12 years; body mass index [BMI]: 45.2 ± 7.8 kg/m2) completed evaluations of STS power, strength and functional performance. STS power was measured with a wearable inertial sensor, strength was assessed with the isometric mid-thigh pull, and function was measured with the timed up-and-go (TUG), six-minute walk test (6MWT) and 30-s chair STS. Power and strength (normalised to body mass) entered regression models in addition to age, gender, BMI and physical activity (daily step count). Power displayed large univariate associations with TUG (r = 0.50) and 30-s chair STS (r = 0.67), and a moderate association with 6MWT (r = 0.49). Forward stepwise regression revealed that power independently contributed to TUG (β = ?0.40, p = 0.010), 30-s chair STS (β = 0.67, p < 0.001) and 6MWT performance (β = 0.27, p = 0.007). Power also appeared to be a superior determinant of function compared with strength. Power generated via the STS transfer largely underpins the ability to perform functional tasks in adults with severe obesity, although intervention studies are required to investigate a potentially causal relationship.  相似文献   
53.
We investigated the associations of cardiometabolic risk factors with academic achievement and whether motor performance, cardiorespiratory fitness, physical activity, or sedentary behaviour mediated these associations. Altogether 175 children 6–8 years-of-age participated in the study. We assessed body fat percentage (BF%), waist circumference, insulin, glucose, triglycerides, HDL cholesterol, and systolic and diastolic blood pressure, leptin, alanine aminotransferase, and gamma-glutamyltransferase (GGT). Reading fluency, reading comprehension, and arithmetic skills were assessed using standardized tests. Speed/agility, balance, and manual dexterity test results were used to calculate motor performance score and physical activity was assessed by combined heart rate and movement sensor and cardiorespiratory fitness by maximal cycle ergometer test. In boys, BF% was inversely associated with reading fluency (β = ?0.262, P = 0.007) and reading comprehension (β = ?0.216, P = 0.025). Motor performance mediated these associations. Leptin was inversely related to reading fluency (β = ?0.272, P = 0.006) and reading comprehension (β = ?0.287, P = 0.003). The inverse association of leptin with reading fluency was mediated by motor performance. In girls, GGT was inversely associated with reading fluency independent of confounders (β = ?0.325, P = 0.007). The inverse association of BF% with academic achievement among boys was largely explained by motor performance. Leptin in boys and GGT in girls were inversely associated with academic achievement independent of confounding factors.  相似文献   
54.
The purpose of this study was to examine the effect of a 12-week resistance training programme on fat-free mass (FFM), muscle cross-sectional area, muscular strength and muscle quality in women who underwent Roux-en-Y gastric bypass surgery. Participants were 16 women (mean age = 44.9 ± 10.2 years) from bariatric surgical groups who were randomly assigned into either a control or an intervention group. Air displacement plethysmography measured FFM and magnetic resonance imaging measured quadriceps muscle cross-sectional area and whole thigh muscle cross-sectional area. Muscular strength and quality was assessed using an estimated 1-Repetition Maximum assessment. All measurements were collected twice, at baseline and at a 12-week follow-up. There were significantly greater improvements in leg press strength (mean differences = 55.4%, P < 0.001, Cohen’s d = 2.4), leg extension strength (mean differences = 18.0%, P = 0.014, Cohen’s d = 0.86) and leg press muscle quality (mean differences = 54.5%, P < 0.001, Cohen’s d = 1.9) in the intervention group compared to the control group following the resistance training programme. The resistance training intervention significantly improved muscular strength and quality; however, it did not illicit changes in FFM or muscle cross-sectional area in women who underwent Roux-en-Y gastric bypass surgery.  相似文献   
55.
通过对当今上海市部分地区青年组(20-29岁)、中年组(50-59岁)两组成年人和经济发达的日本东京市部分地区及我国中部的山西太原市部分地区同龄人身体成分进行比较研究,进一步明确这几个城市该年龄段人群身体成分状况、肥胖程度及肥胖部位的异同,并且通过对长岭公式推算的体脂百分比与欧姆龙生物电阻抗测得的体脂百分比进行比较研究,从而检验铃木-长岭和Brozek体脂率预测公式是否适用于中国国民.结果显示:(1)东京市和太原市青年男女身高、体重均大于上海市;中年男子没有差异;中年女子东京市身高低于上海市、体重高于上海市,太原市中年女子身高高于东京市但没有差异,体重略高于东京市,太原市中年女子身高低于上海市而体重略高于上海市;(2)上海市、东京市和太原市成年人身体肥胖部位不一样、肥胖的敏感部位不同,上海市成年人的脂肪敏感部位主要为腹部,东京成年人的敏感部位主要为上臂皮褶厚度和肩胛部皮褶厚度、太原市成年人的敏感部位主要为臀围和上臂皮褶厚度;(3)铃木-长岭和Brozek体脂率推测公式不适用于我国国民.  相似文献   
56.
肥胖已经成为危险人类健康的常见慢性疾病,而运动是目前公认的治疗肥胖最为有效的方法之一。AMPK(腺苷酸活化蛋白激酶)是一种比较重要的代谢性应激蛋白激酶,在全身的能量平衡中起着总开关的作用。LKB1可以活化细胞中的AMPK,AMPK使ACC(乙酰辅酶A羧化酶)磷酸化失活,脂肪酸合成减少、氧化分解增加,从而预防肥胖的发生发展。肥胖状态下,AMPK磷酸化水平降低,ACC活性增强,脂肪酸合成增加、氧化速率下降。而运动是改善肥胖的重要手段,可以使AMPK磷酸化增强,ACC活性减弱。主要阐述肥胖状态下LKB1-AMPK-ACC信号传导通路各级联蛋白的变化趋势,以及运动干预对各级联蛋白含量的影响。  相似文献   
57.
Previous analyses (i.e., Bernstein & St. John, 2006; Sender & Sullivan, 2008) of the television show The Biggest Loser have detailed its negative presentation of the obese body, potential consequences for viewers, and its role as a technology of governmentality. However, there has been little exploration of how audience members conceptualize and enact the messages communicated in the show within these intricate frameworks. The current research used information from semistructured interviews with 40 dedicated viewers to capture the salient meanings they ascribed to The Biggest Loser within the themes of governmentality and self-concept. Overall, the group experienced the program as a transformative, entertaining, and inspirational event that produced little change in their exercise behavior. Thus, the role of reality television in creating healthy behavior change is potentially limited.  相似文献   
58.
Abstract

The purpose of this study was to examine the relationship between motor proficiency and body mass index (BMI) in preschool children. Thirty-eight children ages 4–6 years had their BMI calculated and were assessed using the Movement Assessment Battery for Children-2 (MABC-2; Henderson, Sugden, & Barnett, 2007). These data were analyzed in two ways. The correlation between BMI and MABC-2 percentile ranks was calculated. Next, the groups were subdivided based on BMI status (high, M = 85.5; medium, M = 49.8; low, M = 10.8), and compared using t tests to determine if differences existed in MABC-2 percentile ranks. No significant relationship existed between MABC-2 and BMI percentile ranks (r = -.237). However, significant differences in MABC-2 percentile ranks existed between high and low (p = .042), and high and medium (p = .043) groups. These results suggest that preschool children classified as overweight or obese may have lower motor proficiency than their normal weight and under weight peers. This study indicates there is a direct relationship between motor proficiency and BMI in the preschool population.  相似文献   
59.
Abstract

The aim of the present study was to identify when body mass index (BMI) is unlikely to be a valid measure of adiposity in athletic populations and to propose a simple adjustment that will allow the BMI of athletes to reflect the adiposity normally associated with non-athletic populations. Using data from three previously published studies containing 236 athletes from seven sports and 293 age-matched controls, the association between adiposity (sum of 4 skinfold thicknesses, in millimetres) and BMI was explored using correlation, linear regression, and analysis of covariance (ANCOVA). As anticipated, there were strong positive correlations (r = 0.83 for both men and women) and slope parameters between adiposity and BMI in age-matched controls from Study 1 (all P < 0.001). The standard of sport participation reduced these associations. Of the correlations and linear-regression slope parameters between adiposity and BMI in the sports from Studies 2 and 3, although still positive in most groups, less than half of the correlations and slope parameters were statistically significant. When data from the three studies were combined, the ANCOVA identified that the BMI slope parameter of controls (5.81 mm · (kg · m?2)?1) was greater than the BMI slope parameter for sports (2.62 mm · (kg · m?2)?1) and middle-distance runners (0.94 mm · (kg · m?2)?1) (P < 0.001). Based on these contrasting associations, we calculated how the BMI of athletes can be adjusted to reflect the same adiposity associated with age-matched controls. This simple adjustment allows the BMI of athletes and non-athletes to be used with greater confidence when investigating the effect of BMI as a risk factor in epidemiological research.  相似文献   
60.
Abstract

This study was designed to assess the effects of a specifically designed perceptual-motor training program on the level of perceptual-motor development, self-concept, and academic ability of kindergarten children. Subjects for the study were 40 kindergarten children randomly assigned to 1 of 2 groups. Each group received the same kindergarten program with one exception, the experimental group was exposed to a specifically designed perceptual-motor program 30 min daily for 5 mo, while the control group received a free play period for 30 min daily. Results of the study indicated that the data tended to support the specificity of training concept. The variables showing the greatest change were the perceptual-motor tests which measured changes on specific aspects of the training program. There appeared to be some immediate transfer to academic abilities but this was not pronounced enough to suggest that perceptual-motor training was of real benefit in developing academic abilities for normal kindergarten children. In addition the follow-up test indicated no long term effects on academic performance.  相似文献   
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