Determinants of exercise capacity in patients with type 2 diabetes

OBJECTIVE: Type 2 diabetes is associated with reduced exercise capacity, but the cause of this association is unclear. We sought the associations of impaired exercise capacity in type 2 diabetes. RESEARCH DESIGN AND METHODS: Subclinical left ventricular (LV) dysfunction was sought from myocardial strain rate and the basal segmental diastolic velocity (Em) of each wall in 170 patients with type 2 diabetes (aged 56 +/- 10 years, 91 men), good quality echocardiographic images, and negative exercise echocardiograms. The same measurements were made in 56 control subjects (aged 53 +/- 10 years, 29 men). Exercise capacity was calculated in metabolic equivalents, and heart rate recovery (HRR) was measured as the heart rate difference between peak and 1 min after exercise. In subjects with type 2 diabetes, exercise capacity was correlated with clinical, therapeutic, biochemical, and echocardiographic variables, and significant independent associations were sought using a multiple linear regression model. RESULTS: Exercise capacity, strain rate, Em, and HRR were significantly reduced in type 2 diabetes. Exercise capacity was associated with age (r = -0.37, P < 0.001), male sex (r = 0.26, P = 0.001), BMI (r = -0.19, P = 0.012), HbA(1c) (A1C; r = -0.22, P = 0.009), Em (r = 0.43, P < 0.001), HRR (r = 0.42, P < 0.001), diabetes duration (r = -0.18, P = 0.021), and hypertension history (r = -0.28, P < 0.001). Age (P < 0.001), male sex (P = 0.007), BMI (P = 0.001), Em (P = 0.032), HRR (P = 0.013), and A1C (P = 0.0007) were independent predictors of exercise capacity. CONCLUSIONS: Reduced exercise capacity in patients with type 2 diabetes is associated with diabetes control, subclinical LV dysfunction, and impaired HRR.     

Influence of combined exercise training on indices of obesity, diabetes and cardiovascular risk in type 2 diabetes patients

OBJECTIVE: To investigate the influence of combined exercise training on indices of obesity, diabetes and cardiovascular risk in type 2 diabetes patients. DESIGN: A double-blind randomized controlled trial with patients receiving either combination (COM), endurance (END) or no training (C). SETTING: Sint-Jozef hospital (Belgium), general practice (Holland). SUBJECTS: Forty-six type 2 diabetes patients (17 female, 29 male). INTERVENTIONS: COM versus END and C. Patients exercised for three months, three times a week for 1 hour. MAIN MEASURES: Six-minute walk test (6MW T), peak Vo(2), strength in upper and lower limbs, sit-to-stand, height, weight, body mass index, fat mass, glycosylated haemoglobin (HbA1c), glycaemia, triglycerides, high-density lipoprotein (HDL), total cholesterol and quality of life (General Health Survey Short Form (SF-36)). RESULTS: COM had significant better results on sit-to-stand (P<0.05), 6MW T (P<0.01), strength in upper (P<0.001) and lower limbs (P<0.001) compared with C. A different evolution among COM and C was found for HbA1c (P<0.05) and cholesterol (P<0.01), both decreased in COM and increased in C. HDL increased in COM and decreased in C (P<0.01). END had significant higher results on the 6MW T (P<0.01) compared with C. Compared with END, COM had significantly higher results on strength in upper (P<0.01) and lower limbs (P<0.01). The evolution of SF-36 items was not significantly different between the three groups. CONCLUSION: In diabetes type 2 patients, COM had significant better effects on indices of physical condition, diabetes and cardiovascular risk compared with C. Compared with END, COM gave a tendency towards better results, however more research with a larger number of participants is needed.     

Assessment of exercise capacity in women with type 2 diabetes

The primary aim of this study was to compare the maximal oxygen uptake as evaluated from a submaximal exercise test (EVO2peak) to direct measurements of VO2peak during a maximal exercise test as means of monitoring the aerobic endurance capacity in women with type 2 diabetes (T2D). Twenty-seven women with T2D participated in the study. The program consisted of combined group training 1 h twice a week during 12 weeks and walks 1 h per week. EVO2 max was estimated using a submaximal exercise test on a bicycle ergometer ad modum Astrand. VO2peak and maximal work rate were measured using an incremental maximal exercise test on an electrically braked bicycle ergometer at baseline and after 6 and 12 weeks. EVO2peak was higher than VO2peak at baseline and significantly higher at 12 weeks (EVO2peak1.92+/-0.54 l min(-1), VO2peak 1.41+/-0.36, P<0.005). Maximal work rate increased significantly after 12 weeks (12+/-15, P<0.005) compared to baseline. The main finding of this study was that EVO2peak assessed using a submaximal exercise test, systematically overestimated VO2peak. The combined group training increased maximal work rate but not VO2peak. This is likely to reflect peripheral adaptation to exercise and/or improved mechanical efficiency.     

Rosiglitazone improves exercise capacity in individuals with type 2 diabetes

OBJECTIVE: Although exercise is recommended as a cornerstone of treatment for type 2 diabetes, it is often poorly adopted by patients. We have noted that even in the absence of apparent cardiovascular disease, persons with type 2 diabetes have an impaired ability to carry out maximal exercise, and the impairment is correlated with insulin resistance and endothelial dysfunction. We hypothesized that administration of a thiazolidinedione (TZD) agent would improve exercise capacity in type 2 diabetes. RESEARCH DESIGN AND METHODS: Twenty participants with uncomplicated type 2 diabetes were randomly assigned in a double-blind study to receive either 4 mg/day of rosiglitazone or matching placebo after baseline measurements to assess endothelial function (brachial artery diameter by brachial ultrasound), maximal oxygen consumption (VO(2max)), oxygen uptake (VO(2)) kinetics, and insulin sensitivity by hyperinsulinemic-euglycemic clamp. Measurements were reassessed after 4 months of treatment. RESULTS: Participant groups did not differ at baseline in any measure. Rosiglitazone-treated participants (n = 10) had significantly improved VO(2max) (19.8 +/- 5.3 ml . kg(-1) . min(-1) before rosiglitazone vs. 21.2 +/- 5.1 ml . kg(-1) . min(-1) after rosiglitazone, P < 0.01), insulin sensitivity, and endothelial function. A change in VO(2max) correlated with improved insulin sensitivity measured by clamp (r = 0.68, P < 0.05) and with improved brachial artery diameter (r = 0.70, P < 0.05). Placebo-treated participants (n = 10) showed no changes in VO(2max) (19.4 +/- 5.2 ml . kg(-1) . min(-1) before rosiglitazone vs. 18.1 +/- 5.3 ml . kg(-1) . min(-1) after rosiglitazone, NS) or brachial artery diameter. CONCLUSIONS: This is the first known report showing that a TZD improved exercise function in type 2 diabetes. Whether this is due to the observed improvements in insulin sensitivity and/or endothelial function or to another action of the TZD class requires further exploration.     

Effects of exercise and cardiac rehabilitation on cardiovascular outcomes

Comprehensive cardiac rehabilitation for coronary patients includes a systematic approach to the measurement and treatment of coronary risk factors, along with the better-known exercise training component. Studies of exercise and nutritional interventions in patients with coronary heart disease have documented improved primary outcomes of decreased morbidity and mortality, decreased symptoms, and fewer cardiac rehospitalizations. Quality of life, depression scores, and physical functioning are improved after rehabilitation.     

抗阻力运动联合有氧运动在2型糖尿病病人治疗中的应用效果评价

[目的]探讨抗阻力运动联合有氧运动对2型糖尿病（T2DM）病人血糖及糖化血红蛋白（HbA1c）值的影响.[方法]将63例确诊为T2DM病人采用随机数字表法分成对照组和观察组.对照组31例给予为期3个月的有氧运动,观察组32例在有氧运动的基础上联合抗阻力运动,运动3个月后测量病人的血糖和HbA1c值.[结果]3个月后两组病人血糖和HbA1c值明显改善（P＜0.05）;观察组病人血糖和HbA1c值低于对照组,两组比较差异有统计学意义（P＜0.05）.[结论]抗阻力运动联合有氧运动以及单纯有氧运动均能改善2型糖尿病病人血糖控制水平,抗阻力运动联合有氧运动效果更佳.     

Effects of cardiac rehabilitation program on exercise capacity and chronotropic variables in patients with orthotopic heart transplant

AIM: To evaluate the effects of home- and hospital-exercise programs on exercise capacity and chronotropic variables in patients with heart transplantation. METHODS: Forty patients were randomized into two groups either hospital- or home-based exercise program. The patients were compared, before and after the rehabilitation program, with respect to maximal oxygen uptake (pVO(2)), chronotropic variables [heart rate reserve (HRR(e)), heart rate recovery (HRR(1)), and chronotropic response index (CRI)] and Duke Treadmill Score (DTS). RESULTS: Hospital-based exercise group has shown a significant recovery in post-exercise pVO(2) (pre-exercise 16.73 +/- 3.9 ml/kg/min, post-exercise 19.53 +/- 3.89 ml/kg/min, P = 0.002) and DTS (pre-exercise 4.74 +/- 1.17, post-exercise 5.61 +/- 1.11, P = 0.002). A significant recovery in favor of the hospital-based exercise group was found in HRR(e) (pre-exercise 26.9 +/- 14.6, post-exercise 34.6 +/- 14.6, P = 0.01). No significant change was observed in HRR(1) (pre-exercise -1.38 +/- 1.04, post-exercise -1.21 +/- 1.89, P = 0.49) and CRI (pre-exercise 0.44 +/- 0.23, post-exercise 0.48 +/- 0.20, P = 0.15) in hospital-based exercise group. No significant change was observed in any parameters of home-based group (P > 0.05). CONCLUSION: A significant recovery was observed both in the functional capacity and the chronotropic response in hospital-based exercise program. Exercise programs that are planned to be performed under supervision in rehabilitation units are useful for the patients with heart transplant in terms of the exercise capacity and chronotropic variables.     

Sex differences in cardiovascular disease risk and exercise in type 2 diabetes

Diabetes currently affects approximately 14% of the US population, and cardiovascular disease (CVD) is a leading cause of morbidity and mortality in those with diabetes. Although in the general population women are at lower risk than men for CVD, women have a disproportionately greater increase in risk for CVD than do men in the context of diabetes. Physical activity is considered a cornerstone in the prevention and treatment of CVD and its risk factors, but greater barriers to physical activity may exist for women with diabetes compared to their male counterparts. In this article, we review sex differences in CVD incidence and risk among diabetics, sex differences in physical activity behaviors, cardiovascular abnormalities and impaired exercise capacity in women living with diabetes, and the effects of exercise on prevention and treatment of CVD in diabetic women. Finally, we discuss future research needed to clarify potential sex differences in the cardiovascular effects of diabetes and to establish ways to reduce the barriers to exercise in women with diabetes.     

Attenuating cardiovascular risk factors in patients with type 2 diabetes

Patients with type 2 diabetes (formerly known as non-insulin-resistant diabetes) have a significantly increased risk of developing cardiovascular disease. Once clinical cardiovascular disease develops, these patients have a poorer prognosis than normoglycemic patients. By inducing endothelial changes, hyperglycemia contributes directly to atherosclerosis. Type 2 diabetes is also associated with atherogenic dyslipidemias. This form of diabetes, or the precursor state of insulin resistance, commonly occurs as a metabolic syndrome (formerly known as syndrome X) consisting of hypertension, atherogenic dyslipidemia and a procoagulant state, in addition to the disorder of glucose metabolism. All cardiovascular risk factors except smoking are more prevalent in patients with type 2 diabetes. In addition to exercise, weight control, aspirin therapy and blood pressure control, therapy to modify lipid profiles is usually necessary. The choice of agent or combination of statin, bile acid sequestrant, fibric acid derivative and nicotinic acid depends on the lipid profile and characteristics of the individual patient.     

运动结合心理疗法对2型糖尿病患者血糖水平的影响

目的：观察运动结合心理疗法治疗前后2型糖尿病患者血糖水平的变化情况.方法：选择2003-01/2004-12在焦作煤业集团中央医院二分院内分泌代谢病科就诊的2型糖尿病患者150例,均知情同意.按入院顺序分为2组,实验组90例,对照组60例.对照组只进行常规治疗,即药物治疗加饮食治疗.实验组在常规治疗的基础上增加运动疗法和心理疗法.[1]运动疗法：将散步、医疗步行、慢跑有机结合作为常规项目.散步速度缓慢、全身放松,10～30 min/次;医疗步行按计划逐渐延长距离、提高步行速度以后可加入爬坡或登阶运动.每日或隔日进行1次;慢跑以有轻度气促,尚能交谈为宜.从5min开始,逐渐延长持续时间.[2]心理疗法：放松训练20 min/次,1次/d;支持性心理疗法为心理健康教育,32次/周,30～45 min/次;音乐治疗20～30 min/次,1次/d.以上治疗4周为1个疗程,共2个疗程.治疗前检测患者的空腹血糖、餐后2 h血糖、糖化血红蛋白水平及24 h尿糖定量,治疗后每周检测1次.治疗前后及治疗2个疗程后检测患者各生化指标的变化情况.疗效判定标准：显效为治疗后症状基本消失,空腹血糖＜7.2 mmol/L,餐后2 h血糖＜8.3 mmol/L,24 h尿糖定量＜10.8 g或血糖24 h尿糖定量较治疗前下降30%以上.有效：治疗后症状明显改善,空腹血糖＜8.3 mmol/L,餐后2 h血糖＜10.0 mmol/L,24 h尿糖定量＜25.8 g或血糖24 h尿糖定量较治疗前下降10%以上.无效：治疗后症状无明显改善,血糖、尿糖下降未达到上述指标.结果：150例患者全部进入结果分析,无脱落.[1]两组患者治疗2个疗程后空腹血糖水平的比较：实验组高于对照组[（6.99&;#177;1.35,6.67&;#177;0.58）mmol/L,（t=1.963,P＜0.05）].[2]两组患者治疗2个疗程后24 h尿糖定量的比较：实验组显著低于对照组[（0.62&;#177;0.31,1.02&;#177;0.49）g,（t=3.298,P＜0.01）].[3]两组患者治疗2个疗程后糖化血红蛋白水平的比较：实验组显著低于对照组[（6.69&;#177;0.96）%,（7.15&;#177;0.82）%（t=2.580,P＜0.01）].[4]两组患者治疗2个疗程后的有效率比较：实验组显著高于对照组[98%,76%（χ^2=9.21,P＜0.01）].结论：运动结合心理疗法是现代医学治疗糖尿病的进一步完善,该疗法体现出的良好的血糖控制作用,治疗有效率显著优于常规疗法.     

运动结合心理疗法对2型糖尿病患者血糖水平的影响

目的:观察运动结合心理疗法治疗前后2型糖尿病患者血糖水平的变化情况。方法:选择2003-01/2004-12在焦作煤业集团中央医院二分院内分泌代谢病科就诊的2型糖尿病患者150例,均知情同意。按入院顺序分为2组,实验组90例,对照组60例。对照组只进行常规治疗,即药物治疗加饮食治疗。实验组在常规治疗的基础上增加运动疗法和心理疗法。①运动疗法:将散步、医疗步行、慢跑有机结合作为常规项目。散步速度缓慢、全身放松,10～30min/次;医疗步行按计划逐渐延长距离、提高步行速度以后可加入爬坡或登阶运动。每日或隔日进行1次;慢跑以有轻度气促,尚能交谈为宜。从5min开始,逐渐延长持续时间。②心理疗法:放松训练20min/次,1次/d;支持性心理疗法为心理健康教育,32次/周,30～45min/次;音乐治疗20～30min/次,1次/d。以上治疗4周为1个疗程,共2个疗程。治疗前检测患者的空腹血糖、餐后2h血糖、糖化血红蛋白水平及24h尿糖定量,治疗后每周检测1次。治疗前后及治疗2个疗程后检测患者各生化指标的变化情况。疗效判定标准:显效为治疗后症状基本消失,空腹血糖<7.2mmol/L,餐后2h血糖<8.3mmol/L,24h尿糖定量<10.8g或血糖24h尿糖定量较治疗前下降30%以上。有效:治疗后症状明显改善,空腹血糖<8.3mmol/L,餐后2h血糖<10.0mmol/L,24h尿糖定量<25.8g或血糖24h尿糖定量较治疗前下降10%以上。无效:治疗后症状无明显改善,血糖、尿糖下降未达到上述指标。结果:150例患者全部进入结果分析,无脱落。①两组患者治疗2个疗程后空腹血糖水平的比较:实验组高于对照组[(6.99±1.35,6.67±0.58)mmol/L,(t=1.963,P<0.05)]。②两组患者治疗2个疗程后24h尿糖定量的比较:实验组显著低于对照组[(0.62±0.31,1.02±0.49)g,(t=3.298,P<0.01)]。③两组患者治疗2个疗程后糖化血红蛋白水平的比较:实验组显著低于对照组[(6.69±0.96)%,(7.15±0.82)%(t=2.580,P<0.01)]。④两组患者治疗2个疗程后的有效率比较:实验组显著高于对照组[98%,76%(χ2=9.21,P<0.01)]。结论:运动结合心理疗法是现代医学治疗糖尿病的进一步完善,该疗法体现出的良好的血糖控制作用,治疗有效率显著优于常规疗法。     

2型糖尿病患者运动习惯的调查

目的 探讨影响2型糖尿病患者运动习惯的相关因素和对策.方法 采用问卷形式对110例2型糖尿病(T2DM)患者进行有关糖尿病运动知识、运动习惯的调查,并对影响患者运动习惯的相关因素进行分析.结果 41.1%患者未接受过运动教育,38.9%患者无良好的运动习惯,30.5%患者对运动治疗根本不重视.分析原因主要与患者对运动知识的知晓程度、对运动治疗重视程度及有无运动陪伴密切相关(P<0.01),与年龄、病程长短、文化程度等关系无统计学意义.结论 帮助患者建立良好的运动习惯能有效提高患者运动遵医行为.     

Effects of exercise on cardiovascular risk factors in type 2 diabetes: a meta-analysis

OBJECTIVE

Exercise is a cornerstone of diabetes management and the prevention of incident diabetes. However, the impact of the mode of exercise on cardiovascular (CV) risk factors in type 2 diabetes is unclear.

RESEARCH DESIGN AND METHODS

We conducted a systematic review of the literature between 1970 and October 2009 in representative databases for the effect of aerobic or resistance exercise training on clinical markers of CV risk, including glycemic control, dyslipidemia, blood pressure, and body composition in patients with type 2 diabetes.

RESULTS

Of 645 articles retrieved, 34 met our inclusion criteria; most investigated aerobic exercise alone, and 10 reported combined exercise training. Aerobic alone or combined with resistance training (RT) significantly improved HbA_1c −0.6 and −0.67%, respectively (95% CI −0.98 to −0.27 and −0.93 to −0.40, respectively), systolic blood pressure (SBP) −6.08 and −3.59 mmHg, respectively (95% CI −10.79 to −1.36 and −6.93 to −0.24, respectively), and triglycerides −0.3 mmol/L (95% CI −0.48 to −0.11 and −0.57 to −0.02, respectively). Waist circumference was significantly improved −3.1 cm (95% CI −10.3 to −1.2) with combined aerobic and resistance exercise, although fewer studies and more heterogeneity of the responses were observed in the latter two markers. Resistance exercise alone or combined with any other form of exercise was not found to have any significant effect on CV markers.

CONCLUSIONS

Aerobic exercise alone or combined with RT improves glycemic control, SBP, triglycerides, and waist circumference. The impact of resistance exercise alone on CV risk markers in type 2 diabetes remains unclear.Diabetes is a chronic condition brought about by the body’s inability to produce enough insulin or to use the insulin that it produces. As a result of this insulin insufficiency, there is an increase in the concentration of glucose in the blood (known as hyperglycemia), as well as other metabolic abnormalities. According to the World Health Organization, the number of individuals with diabetes worldwide has increased from 30 million in 1985 to 171 million in 2000 (1); these rates are expected to further increase, with the World Health Organization predicting that the worldwide prevalence in adults will reach 6.4% by 2030, corresponding to a 39% increase from 2000 to 2030 (2). Of the diagnosed cases of diabetes, it is estimated that approximately 90–95% of individuals have type 2 diabetes (3).Type 2 diabetes is an independent risk factor for both macrovascular disease (e.g., myocardial infarction and stroke) and microvascular disease (e.g., retinopathy and nephropathy), and is often associated with other cardiovascular (CV) disease (CVD) risk factors, including high blood pressure (BP), dyslipidemia, obesity, lack of physical activity, and smoking (4,5). Although glycemic control is a key therapeutic target for individuals with type 2 diabetes, the major cause of morbidity and mortality among this patient population is CVD, not metabolic dysregulation (6). CVD is the leading cause of mortality among individuals with diabetes (7,8), accounting for 65% of all deaths among this patient group (9). Furthermore, diabetes is twice as common among populations of patients with heart failure when compared with matched control subjects (10), and patients with diabetes are more likely to develop heart failure after a myocardial infarction than nondiabetic individuals (11).Exercise has long been recognized as a cornerstone of diabetic management and the prevention of incident diabetes. For example, the American College of Sports Medicine currently recommends that individuals with type 2 diabetes expend a minimum cumulative total of 1,000 kcal per week of energy from physical activities (12). Meta-analyses have shown that aerobic or resistance training (RT) is related to statistically significant improvements in glycemic control (13–15). Support for the effect of exercise on other CV risk factors, however, is lacking. Therefore, we conducted this review to investigate the effects of aerobic exercise, RT, and combined aerobic and RT on CV risk factors in type 2 diabetes.     

社区运动干预对2型糖尿病患者的影响

目的探讨有计划、有针对性的运动干预对社区糖尿病患者改善自身健康状况及血糖控制效果的影响。方法选择社区102例无运动禁忌证、在饮食控制和原有药物治疗的前提下进行有效运动干预的患者。运动治疗6个月、12个月后分别对体重、腹围、血压、空腹血糖(FBG)、餐后2h血糖(PBG)、糖化血红蛋白(HbA1c),血脂等指标进行测定,并和干预前检查的各项指标比较。结果运动干预6个月后患者的FBG、PBG、HbA1c、舒张压与干预的比较差异有统计意义(P0.01)。体重指数、腹围、甘油三酯(TG)、胆固醇(TC)、收缩压干预12个月后差异有统计学意义(P0.01)。结论运动干预对社区糖尿患者改善自身身体状况、控制血糖效果明显,应引起患者家庭和社区的重视和支持。     

2型糖尿病患者锻炼自我效能与体育锻炼的相关性研究

目的描述2型糖尿病患者的锻炼自我效能,探讨锻炼自我效能与体育锻炼的相关性。方法采用锻炼自我效能量表和业余体育活动问卷,用方便抽样方法调查117例2型糖尿病患者。结果2型糖尿病患者锻炼自我效能均分为（52．42±18．30）分,患者锻炼自我效能与过去1年平均每周体育锻炼时间呈正相关（r=0．415,P〈0．01）,与过去1年平均每周体育锻炼能量支出呈正相关（r=0．452,P〈0．01）。结论2型糖尿病患者锻炼自我效能处于中等水平,2型糖尿病患者锻炼自我效能越高,过去1年平均每周体育锻炼时间越多,体育锻炼能量支出越多。