NIOSH提举指数在下背痛流行病学研究中的应用

[目的 ]探讨美国国家职业安全卫生研究所提出的手工作业提举指数 (LI)与下背痛患病率的关系。[方法 ]在 3个具有典型提举作业的工厂中采用流行病学横断面调查方法 ,利用NIOSH提出的提举指数进行接触负荷评价 ,按照Nordic肌肉骨骼症状分析调查表对 491名从事手工提举作业的工人和 3 4名无明显提举任务的行政人员进行问卷调查 ,并对静态肌力进行测试。根据提举指数分为 0 ,～ 1,～ 2 ,～ 3 ,>3共 5组。观察各组工人不同部位肌肉骨骼疾患的患病情况 ,并分析提举指数与下背痛患病的关系。 [结果 ]在肌肉骨骼症状中 ,下背痛的发生率最高。当LI增高时 ,下背痛的OR值也随之增加 ,但其峰值出现在～ 3组 (OR =1.3 5 ) ,而LI >3 ,其OR值并非最高 ,仅为 1.3 0。平均腰拉力最大的为～ 1组 ( 95 .5 9± 2 1.76)kg ,而对照组和LI >3组则分别为 ( 80 .3 6± 14 .49)kg、( 86.85± 2 0 .3 3 )kg。 [结论 ]提举指数对手工提举所引起的下背痛是一个有意义的危险度评价指标。过度手工提举活动可能降低腰拉力。     

工人和学生最大静态肌力的测定与分析

目的测量工人和学生两组人群的最大肌力,为制定适合我国人群的手工搬举标准提供依据。方法按照《人体测量学指导手册》测定938名受试者的基本人体尺寸,通过拉力测试系统测定受试者的背提力、左右手提力、手臂提力和肩提力。结果测得男性背提力、左右手提力、手臂提力、肩提力的最大值男性分别为1 077.0、576.9、609.0、318.3、465.1N,女性分别为602.0、306.6、340.9、181.8、252.3N。背提力最大,手臂提力最小。男性受试者人体尺寸和最大肌力呈现一定的相关性(P0.05)。结论中国人背提力、单手提力、手臂提力和肩提力均低于欧美人群。女性各种肌力均比男性小,总体上是男性肌力的55%左右。在女性当中左手肌力小于右手肌力更加明显。     

几种最大静态肌力的测定和分析

目的　测定一定姿势下的最大静态肌力 ,探讨影响其大小的相关因素 ,为工效学设计和筛选劳动者提供依据。方法　以大学生志愿者 83人 (男 4 3人 ,女 4 0人 )为对象 ,在实验室测定其双手推、拉、提和左、右手单手提 5个动作的最大静态肌力 ,并测量体重、身高、肩高、髋关节高及臂长等人体数据。结果　实验对象的双手推力、拉力、提力和左、右手提力的最大值男性分别为 2 5 2 7,312 8,337 6 ,5 6 4 8,6 0 2 4N ,女性分别为 14 4 5 ,178 2 ,178 9,2 6 7 8,2 6 6 3N ;人体尺寸数据与力的相关分析表明 ,身高、体重、臂长与力的相关具有显著性 (P <0 0 1)。结论　本实验对象的最大静态肌力明显小于欧美人相应的测定数据 ,身高和体重可预测双手的推、拉和提力大小 ,但不适用于单手提力 ,女性受试者的最大静态肌力明显小于男性 ,这些对工效学设计和劳动者筛选具有参考意义。     

中国10个地区成年人骨骼肌质量和手握力的描述性分析

目的 描述中国10个地区成年人骨骼肌质量和手握力的地区和人群分布特征。方法 对来自中国慢性病前瞻性研究项目第2次重复调查的24 533名研究对象进行分析。采用生物电阻抗分析法测量四肢和躯干的肌肉质量,通过Jamar手持握力计测量手握力来衡量肌肉力量水平,并根据亚洲肌少症工作组（AWGS）推荐的标准判断人群低肌肉质量和力量的比例。分地区和人群特征,报告肌肉质量和手握力的均值及标准误,以及低肌肉质量和力量的百分比。结果 男性的四肢和全身肌肉质量分别为（22.0±0.02）kg和（49.7±0.05）kg,高于女性的（15.9±0.02）kg和（37.2±0.04）kg;男性手握力为（32.6±0.06）kg,高于女性的（19.9±0.05）kg。绝对肌肉质量和手握力均呈现北方高于南方、城市高于农村的地区差异（P<0.001）。而身高和体重调整的肌肉质量的地区差异规律相反。随着年龄的增加,肌肉质量各项指标和手握力均呈线性下降趋势（线性趋势P<0.001）,且手握力下降幅度更大。进一步按照AWGS判断,低肌肉质量和力量的比例随年龄增加而不断上升,≥ 80岁的老年男性低肌肉质量和力量的比例分别达到56.2%和74.5%,女性分别达到35.7%和66.0%。结论 中国成年人肌肉质量和手握力的分布存在明显的地区和人群差异,尤其以老年人低肌肉质量和手握力的比例最高。     

事业单位人员脂肪肝患病情况及与体重指数、血脂水平的关系

目的了解事业单位人员的脂肪肝患病情况及与体重指数(BMI)、血脂水平的关系,为改善事业单位人员健康状况提供依据。方法以2008年参加体检的部分事业单位人员813名为研究对象,对其进行脂肪肝检查,身高、体重测量和血脂检测,分析事业单位人员脂肪肝患病情况,及其与BMI、血脂水平的关系。结果肪事业单位人员脂肪肝检出率男性为59.09%、女性为39.41%;19~45岁年龄组脂肪肝检出率为26.02%,46~59岁年龄组为58.01%,≥60岁年龄组为49.67%,各年龄组脂肪肝检出率男性均高于女性。脂肪肝患病组BMI、血清甘油三酯水平分别为(27.08±3.11)kg/m2、(2.14±1.26)mmol/L,与非脂肝组的(22.19±3.02)kg/m2、(1.60±0.81)mmol/L比较,差别有统计学意义(P<0.01)。结论事业单位人员脂肪肝患病率较高,且患病人群的体重和甘油三酯水平较高。     

武警某部战士、学员力量素质的研究

目的 :对武警某部战士、学员的力量素质进行测定和评价 ,为指导部队力量素质训练提供基础资料。方法 :(1)对武警某部 770名战士、学员按军标规定的方法和标准 ,测定握力、背肌力、引体向上以及俯卧撑等指标 ,并进行评价 ;(2 )计算“力量素质综合分” ,以对样本中三个单位进行差异比较。结果 :(1)武警某部战士和学员的右手握力为 (42 .37± 6 .0 3)kg ,背肌力为(132 .96± 2 2 .96 )kg ,引体向上为 (10 .4 5± 4 .2 0 )次 ;俯卧撑为 (46 .91± 14 .90 )次·min- 1。总体评价背肌力和俯卧撑良好 ,右手握力和引体向上中等。 (2 )样本中三个单位“力量素质综合分”的比较结果表明 ,两两之间差异不显著 (F =0 .2 4 5 ,P >0 .0 5 )。结论 :武警某部战士、学员力量素质总体情况尚好 ,但握力和引体向上两指标显示较薄弱 ,应该有针对性地加大科学训练力度     

广州市6~9岁儿童握力及握力指数研究

目的 探讨广州市6~9岁儿童握力及握力指数大小,为儿童肌肉和力量发育评估及临床测试标准提供参考依据。方法 2016年1-12月在广州市招募474名6~9岁儿童,采用Jamar握力计进行握力测试,并测量体重,计算握力体质量指数。结果 以1岁为一个年龄段,6~9岁男童左(右)手握力均值±标准差分别为7.9±1.7(8.5±1.9),9.5±2.0(10.3±2.3),11.0±2.8(11.6±3.0),12.3±2.5(13.2±2.8)kg;女生分别为7.3±2.0(7.7±2.0),8.3±1.6(8.9±1.7),9.8±2.3(10.7±2.5),10.2±2.2(11.4±2.7)kg;男童左(右)手握力指数均值±标准差分别为36.1±7.3(38.9±7.5),39.1±7.7(42.3±8.0),38.7±7.9(41.2±8.7),38.5±9.6(41.0±10.0);女童则分别为35.2±8.8(36.6±8.3),36.1±6.5(38.7±6.3),37.0±7.7(40.3±8.0),37.4±7.6(41.6±9.0)。男、女童右手握力、握力指数均显著高于左手,同侧手男生握力、握力指数在各年龄段均显著高于女生(P<0.05)。随着年龄增加,男女童握力均显著增高。男生左右手握力指数及女生左手握力指数在各年龄段间差异无统计学意义。结论 初步建立了广州市6~9岁学龄儿童握力、握力指数的参考值范围。     

糖尿病患者的营养评价及其少肌症发生的影响因素

目的　了解糖尿病患者的营养状况及其少肌症的影响因素。方法　对2013年1月至2014年12月北京医院营养科门诊297例糖尿病患者进行回顾性分析,比较非超重组［体质量指数（BMI）≤23.9 kg/m2］与超重组(BMI≥24.0 kg/m2)人体测量指标、身体成分、实验室检查指标、膳食摄入的差别,并分析糖尿病患者少肌症发生的影响因素。结果　超重组183例、非超重组114例,非超重组左手握力、右手握力、腰臀比及臂肌围均低于超重组［（24.14±7.76）kg比（27.78±9.31）kg,P=0.00;（25.55±7.86）kg比（28.62±9.55）kg, P=0.01;0.85±0.06比0.92±0.07,P=0.00;（21.45±3.73）cm比（25.18±4.36）cm,P=0.00］;非超重组的肌肉量、体脂百分比、内脏脂肪面积及骨骼肌指数均低于超重组［（37.64±6.58）kg比（45.66±8.92）kg;（27.25±8.15）%比（35.52±6.56）%;（71.56±25.28）cm2比（118.84±28.18）cm2;（6.22±1.17）kg/m2比（7.41±1.25）kg/m2］(P均=0.00）;非超重组血红蛋白水平低于超重组［（136.29±14.81）g/L比（141.01±13.47）g/L, P=0.03］;两组总蛋白及白蛋白水平差异无统计学意义（P=0.15,P=0.52）;非超重组血糖水平低于超重组［（7.08±2.28）mmol/L比（7.76±2.57）mmol/L,P=0.03］;非超重组与超重组的能量及蛋白质摄入差异无统计学意义（P=0.17,P=0.35）。糖尿病患者少肌症的检出率为10.4%（31/297）,非超重患者的少肌症检出率高于超重患者（22.8%比2.7%,P=0.00）。回归分析结果显示,女性（B=-1.371,95% CI=-1.595～-1.146)、增龄(B=-0.018,95% CI=-0.027～-0.009)、低BMI(B=-0.115,95% CI=0.092～0.138)、能量摄入的减少(B=0.014,95% CI=0.000～-0.029）是骨骼肌指数降低的主要危险因素。结论　糖尿病患者BMI在适度超重的范围内有更好的营养状态,有利于预防少肌症的发生。     

化工工人肌肉骨骼功能及其与工作能力的关系

目的 研究化工工人肌肉骨骼功能状况及其与工作能力的关系。方法 对101名化工作业工人进行肌肉骨骼功能(背肌耐力、手握力、躯干柔韧性、腹肌力和肌肉骨骼功能指数)测定和工作能力指数(wAI)测定。结果男性握力显著高于女性(P＜O.01)，腹肌力、背肌耐力和肌肉骨骼功能指数(MSFI)均男性较高，躯干柔韧性女性较高；年龄与MSFI呈负相关(r=O．489，P＜O．01)，随年龄增加，肌肉骨骼功能下降；不同劳动类型化工职工肌肉骨骼功能差异无显著性；肌肉骨骼功能与工作能力之间存在密切的关系，MSFI与WAI的相关系数为O.215(P＜O．05)，MSFI分级和WAI分级间有较好的一致性，完全一致率为56．7％。结论 肌肉骨骼功能的测定对于评价化工工人工作能力可能具有重要的意义。     

坐位工人身体紧张状态的生物力学分析

本文采用Occhipintis数学模型和人体测量学方法,对90名坐位作业工人静力紧张进行了生物力学分析。结果表明:(1)男性工人的第三腰椎以上身体各解剖节段体重和臂支撑地面反应力均明显大于女性;(2)男性的臂支撑力占体重的百分比,要比女性大约5％;(3)不同性别的腰背肌静力紧张时张力相近似,L_(3～4)椎间盘的压力也无明显差别;(4)腰背肌张力(F_mL_3)和腰椎间盘压力(PL_3)随年龄增加而改变。本方法简便、易行、利于推广。     

Muscle strength in obese elderly women: effect of recreational physical activity in a cross-sectional study

BACKGROUND: Muscle strength (MS) may be impaired in obese persons, and this impairment may be a consequence of both obesity and low physical fitness. OBJECTIVE: We investigated whether MS differed between obese [body mass index (BMI; in kg/m2 > 29], normal-weight (BMI = 24-29), and lean (BMI < 24) elderly subjects and compared the MS of sedentary and active subjects according to their BMI group. DESIGN: The study included 215 obese [ (+/- SD) age: 80.0 +/- 3.5 y; BMI: 31.9 +/- 2.6], 630 normal-weight (age: 80.2 +/- 3.7 y; BMI: 26.3 +/- 1.4), and 598 lean (age: 80.7 +/- 3.5 y; BMI: 21.6 +/- 1.8) women with good functional ability. A cross-sectional design was used. Anthropometric measures (weight, height); measures of appendicular skeletal muscle mass (by dual-energy X-ray absorptiometry), isometric knee and elbow extension (by statergometer), and isometric handgrip strength (by dynamometer); and data on health status and self-reported recreational physical activity (RPA: walking, gymnastics, cycling, swimming, gardening) were collected. RESULTS: Absolute (unadjusted) MS was higher in obese than in lean women (P < 0.01), except for handgrip strength (P > 0.05). When adjusted for age, height, RPA, pain, depression, and appendicular skeletal muscle mass, MS did not differ significantly between obese, normal-weight, and lean subjects, except for knee extension (significant interaction effect with RPA; P = 0.01). With increasing BMI, lower limb strength did not change in the sedentary women but increased in active (> or = 1 h/wk in > or = 1 RPA for > or = 1 mo) women. All adjusted MS measures in active participants were significantly higher (P < 0.001) than those in their sedentary peers. CONCLUSION: The adjusted MS of elderly women is not associated with obesity but is higher in active subjects than in sedentary ones, especially in the lower limbs of obese subjects.     

The association between nutritional status and handgrip strength in older Rwandan refugees

OBJECTIVES: To investigate the association between nutritional status and handgrip strength in older Rwandan refugees. DESIGN: Cross-sectional study. SETTING: Rwandan refugee camp located in Karagwe district in the north-west of Tanzania. The study was carried out in the post-emergency phase. The response rate was 85%. SUBJECTS: A total of 413 men and 415 women aged 50-92 y participated in the study. METHODS: Weight, height, mid-upper-arm circumference (MUAC) and triceps skinfold were obtained using standard techniques. For people with visible kyphosis, height was estimated from armspan using regression equations developed from non-kyphotic subjects within the sample. Handgrip was measured using a mechanical handgrip dynamometer. Information regarding physical activity and health status was obtained by interview and clinical screening. RESULTS: Handgrip strength (kg) was significantly higher in men than in women (30.3+/-6.7 vs 22.3+/-5.1), and significantly lower in each older age group in both sexes. Handgrip strength was positively correlated to BMI (body mass index) and AMA (arm muscle area). The relative risk of impaired handgrip strength in individuals with poor nutritional status (BMI<18.5 kg/m(2)) compared with those of adequate nutritional status was 1.75. After controlling for potential confounders (sex, age and height), BMI remained a significant contributor to the variation in handgrip strength. CONCLUSION: Poor nutritional status is associated with poor handgrip strength independent of sex, age and height, in this refugee population. This may indicate that underweight older people are likely to have more difficulties in functioning independently in the community. Research is needed to investigate if improving nutritional status can lead to better functional ability. SPONSORSHIP: Department for International Development (UK) and HelpAge International.     

Efficacy of nutritional supplementation therapy in depleted patients with chronic obstructive pulmonary disease

OBJECTIVE: Weight loss and muscle wasting adversely affect morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD). Maintenance systemic glucocorticosteroids, prescribed in a substantial number of patients, further contribute to muscle weakness. We investigated the efficacy of oral nutritional supplementation therapy in depleted patients with COPD. METHODS: The therapy consisted of daily two to three oral liquid nutritional supplements (mean +/- standard deviation: 2812 +/- 523 kJ/24 h) incorporated into an 8-wk inpatient pulmonary rehabilitation program in 64 (49 men) depleted patients with COPD. Endpoints were body weight, fat-free mass by bioelectrical impedance analysis, respiratory and peripheral muscle function (maximal inspiratory mouth pressure and handgrip strength, respectively), exercise performance (incremental bicycle ergometry), and disease-specific health status by St. George's Respiratory Questionnaire. Forty-eight percent of the patients were treated with low-dose oral glucocorticosteroids as maintenance medication (dose equivalent to 7.6 +/- 2.5 mg of methylprednisolone per day). RESULTS: Increases in body weight (2.1 +/- 2.1 kg, P < 0.001) and fat-free mass (1.1 +/- 2.0 kg, P < 0.001) were seen. Further, maximal inspiratory mouth pressure (4 +/- 10 cm of H(2)O, P = 0.001), handgrip strength (1.2 +/- 3.1 kg, P = 0.004), and peak workload (7 +/- 11 W, P = 0.001) significantly improved. Clinically significant improvements in the items symptoms (9 +/- 16 points, P < 0.001) and impact (4 +/- 15 points, P = 0.043) of St. George's Respiratory Questionnaire were achieved. Oral glucocorticosteroid treatment significantly impaired the response to nutritional supplementation therapy with respect to maximal inspiratory mouth pressure, peak workload, and St. George's Respiratory Questionnaire symptom score. CONCLUSIONS: Nutritional supplementation therapy implemented in a pulmonary rehabilitation program was effective in depleted patients with COPD. However, oral glucocorticosteroid treatment attenuated the anabolic response to nutritional supplementation.     

学龄儿童握力水平与体成分的相关性研究

目的 研究学龄儿童青少年体成分与握力的相关性,对学龄肥胖儿童干预过程中维持合适的体成分具有重要意义。方法 2018年对北京市15 118名6~16岁学龄儿童进行问卷调查(生活方式、膳食、运动)、生物电阻抗体成分检测和优势手握力检测,并采用偏相关、多元线性回归对握力与体成分指标的相关性进行分析。结果 北京市儿童青少年的握力水平随年龄增长逐渐升高,男童正常体重组握力水平由6~8岁组的(9.7±2.6)kg增长到15~16岁组的(40.0±7.1)kg,女童正常体重组由6~8岁组的(8.9±2.6)kg增长到15~16岁组的(25.0±4.4)kg,与上肢骨骼肌质量指数变化趋势一致;男生高于女生;调整相关因素后,瘦体重质量指数及上肢骨骼肌质量指数与握力水平均呈正相关(男童:r=0.597,0.258;女童:r=0.424,0.102,P<0.05)。结论 握力可反映骨骼肌水平变化趋势。增加瘦体重,减少脂肪可提高握力水平。     

Occupational health studies on airport transport workers

Summary Airport transport workers do manual work in loading and unloading the cargo space of passenger airplanes. In several types of airplanes the work has to be carried out in narrow spaces and in cramped positions. The present study describes the isometric strength of some muscle groups in 70 airport transport workers. Trunk extensors, trunk flexors, muscles involved in bimanual vertical lifting, elbow extensors, and elbow flexors were measured. A method with fixed positions and strictly isometric contractions was used. The strengths of the different muscle groups correlated with each other and with body weight; those of lifting, trunk flexors and biceps also with stature. The absolute strength of the muscle groups declined with advancing age at rates from 0.3% to 1.5% per year, the relative strength (N/kg body weight) by 0.9%–2.0% per year.     

Evaluation of handgrip strength as a nutritional marker and prognostic indicator in peritoneal dialysis patients

BACKGROUND: Serum albumin has limitations as a nutritional marker in patients undergoing peritoneal dialysis (PD) in that it is affected by inflammation, systemic disease, overhydration, and urinary and dialysate protein loss. Handgrip strength is a simple, easily performed bedside test that has been shown to correlate with lean body mass in patients close to inception of dialysis. OBJECTIVE: We evaluated the associations of handgrip strength with other clinical factors and examined its relations with mortality and cardiovascular death in PD patients. DESIGN: We prospectively enrolled 233 chronic PD patients and assessed handgrip strength and other variables at baseline and then followed the patients for a mean (+/-SD) of 30 +/- 14 mo. RESULTS: Baseline handgrip strength was significantly associated with age, sex, height, diabetes, residual glomerular filtration rate (GFR), and hemoglobin but not with C-reactive protein (CRP). After adjustment for age, sex, and height, handgrip strength was most strongly correlated with lean body mass on the basis of creatinine kinetics (r = 0.334, P < 0.001), followed by serum albumin and subjective global assessment. Both men and women who died had lower handgrip strengths than did those who remained alive (P < 0.001). After control for age, sex, diabetes, atherosclerotic vascular disease, GFR, hemoglobin, CRP, and serum albumin, greater handgrip strength was predictive of lower all-cause [hazards ratio (HR): 0.95 (95% CI: 0.92, 0.99); P = 0.005] and cardiovascular [HR: 0.94 (0.90, 0.98); P = 0.004] mortality. CONCLUSIONS: Handgrip strength not only is a marker of body lean muscle mass but also provides important prognostic information independent of other covariates, including CRP and serum albumin. Our data suggest that handgrip strength may be used in conjunction with serum albumin as a nutrition-monitoring tool in patients undergoing PD.     

Daily multi-micronutrient supplementation during tuberculosis treatment increases weight and grip strength among HIV-uninfected but not HIV-infected patients in Mwanza, Tanzania

Undernutrition is common among tuberculosis (TB) patients. The objective of this study was to assess the effect of multi-micronutrient supplementation during TB treatment on weight, body composition, and handgrip strength. A total of 865 patients with smear-positive (PTB+) or -negative (PTB-) pulmonary TB were randomly allocated to receive a daily biscuit with or without multi-micronutrients for 60 d during the intensive phase of TB treatment. Weight, arm fat area, arm muscle area, and handgrip strength were assessed at baseline and after 2 and 5 mo. At 2 mo, the multi-micronutrient supplementation led to a higher handgrip gain (1.22 kg; 95% CI = 0.50, 1.94; P = 0.001) but had no effects on other outcomes. The effects of multi-micronutrient supplementation were modified by HIV infection (P-interaction = 0.002). Among HIV- patients, multi-micronutrient supplementation increased weight gain by 590 g (95% CI = -40, 1210; P = 0.07) and handgrip strength by 1.6 kg (95% CI = 0.78, 2.47; P < 0.001), whereas among HIV+ patients, it reduced weight gain by 1440 g (95% CI = 290, 2590; P = 0.002) and had no effect on handgrip strength (0.07 kg; 95% CI = -1.30, 1.46; P = 0.91). The reduced weight gain among HIV+ patients receiving multi-micronutrient supplementation seemed to be explained by a higher proportion of patients reporting fever. At 5 mo, the effects on weight were sustained, whereas there was no effect on handgrip strength. In conclusion, multi-micronutrient supplementation given as a biscuit is beneficial among HIV- PTB patients and may be recommended to TB programs. More research is needed to develop an effective supplement for HIV+ PTB patients.     

Weight, body composition and handgrip strength among pulmonary tuberculosis patients: a matched cross-sectional study in Mwanza, Tanzania

This study aimed to estimate deficits in weight, arm fat area (AFA), arm muscle area (AMA) and handgrip strength among smear-positive pulmonary TB (PTB+) patients starting treatment. We conducted a cross-sectional study among PTB+ patients and age- and sex-matched neighborhood controls. HIV status, anthropometric measurements and handgrip strength were determined. Deficits in weight, AFA, AMA and handgrip strength associated with PTB+ and HIV were estimated using multiple regression analysis.We recruited 355 pairs of PTB+ patients and controls. PTB+ was associated with deficits of 10.0 kg (95% CI 7.3; 12.7) in weight and 6.8 kg (95% CI 5.2; 8.3) in handgrip strength among females and 9.1 kg (95% CI 7.3; 10.9) in weight and 6.8 kg (95% CI 5.2; 8.4) in handgrip strength among males. In both sexes, PTB+ was associated with deficits in AFA and AMA. Among females, HIV was associated with deficits in AMA and handgrip strength, but the deficit in handgrip strength was larger among PTB+ patients (3.2 kg 95% CI 1.3; 5.2) than controls (-1.6 kg 95% CI -4.8; 1.5) (interaction, P = 0.009).These findings suggest that deficits in weight and handgrip strength among patients starting TB treatment are severe. Thus, nutritional support may be necessary to ensure reversal of the deficits, and may improve treatment outcomes.     

Creatine supplementation differentially affects maximal isometric strength and time to fatigue in large and small muscle groups.

Ten physically active, untrained, college-aged males (26.4 +/- 5. 8 years old) received creatine (CR, 5 g creatine monohydrate + 3 g dextrose) and placebo (PLA, 7 g dextrose) supplementation four times per day for 5 days in a double-blind, randomized, balanced, crossover design. Performance was assessed during maximal and three repeated submaximal bouts of isometric knee extension and handgrip exercise. CR supplementation significantly increased (p <.05) maximal isometric strength during knee extension but not during handgrip exercise. CR supplementation increased time to fatigue during each of the three bouts of submaximal knee extension and handgrip exercise when compared to the PLA trials. These findings suggest that CR supplementation can increase maximal strength and time to fatigue during isometric exercise. However, the improvements in maximal isometric strength following CR supplementation appear to be restricted to movements performed with a large muscle mass.     

L-ornithine alpha-ketoglutarate in HIV infection: effects on muscle, gastrointestinal, and immune functions

OBJECTIVES: There have been claims that l-ornithine alpha-ketoglutarate (OKG) exerts anticatabolic, anabolic, and immunomodulating properties. This study aimed at quantifying the effects of OKG on muscle force, body composition, and immune function in outpatients infected with the human immunodeficiency virus (HIV) and presenting weight loss. METHODS: Forty-six HIV(+) patients were included in a double-blind, prospective, randomized, controlled trial for 12 wk (10 g/d of OKG or isonitrogenous placebo and nutritional counseling). Podometry, handgrip strength, step test, triceps skinfold thickness, 50-kHz bioelectrical impedance, 3-d diet record, CD4 cell count, HIV-1 RNA concentration (viral load), and gastrointestinal symptoms were assessed at 0, 4, 8, and 12 wk. RESULTS: At baseline, patients (OKG, n = 22; placebo, n = 24) has similar CD4 counts (338 +/- 172 and 310 +/- 136 cells/mL), viral load (3.6 +/- 1.3 and 3.5 +/- 1.3 log(10) copies/mL), body mass index (20.0 +/- 2.4 and 20.6 +/- 3.0 kg/m(2)), weight loss (9.0 +/- 3.12 and 9.4 +/- 3.0 kg), and food intake (2509 +/- 962 and 2610 +/- 808 kcal/d). Twenty-nine patients completed the protocol. Both groups increased their body mass index (P = 0.02 versus baseline) and triceps skinfold thickness (P < 0.01 versus baseline). They showed a similar positive correlation between handgrip strength and fat-free mass. Frequency of gastrointestinal symptoms increased in the OKG group (86% versus 54% in the placebo group, P = 0.025). No other differences were observed between groups. CONCLUSIONS: All patients increased their body mass index and triceps skinfold thickness due to food supplementation and diet counseling. Oral OKG failed to improve nutritional, functional, or immunologic status in these weight-losing HIV(+) patients and had important gastrointestinal side effects.