Exercise and glycemic control in diabetes: benefits, challenges, and adjustments to pharmacotherapy

Effects of neuromuscular electrical stimulation on glycemic control: a systematic review and meta-analysis

Background

Physical inactivity increases the risk for metabolic diseases such as obesity and type 2 diabetes. Neuromuscular electrical stimulation (NMES) is an effective method to induce muscle contraction, particularly for populations with physical impairments and/or metabolic diseases. However, its effectiveness to improve glycemic control is unclear. This review aimed to determine the effectiveness of NMES on glycemic control.

Methods

Electronic search consisted of MEDLINE (PubMed), EMBASE, Cochrane Library, Google Scholar, and Web of Science to identify studies that investigated the effects of NMES on glycemic control for this systematic review. The meta-analysis consists of the studies designed as randomized controlled trials. Effect sizes were calculated as the standardized mean difference (SMD) and meta-analysis was conducted using a random-effects model.

Results

Thirty-five studies met the inclusion criteria for systematic review and of those, nine qualified for the meta-analysis. Existing evidence suggested that NMES effectively improves glycemic control predominantly in middle-aged and elderly population with type 2 diabetes, obesity, and spinal cord injury. The meta-analysis is comprised of 180 participants and reported that NMES intervention lowered fasting blood glucose (SMD: 0.48; 95% CI: 0.17 to 0.78; p=0.002; I²=0%). Additional analysis using the primary measures reported by each study to indicate glycemic control (i.e., OGTT, HOMA-IR, and fasting glucose) also confirmed a significant effect of NMES on improving glycemic control (SMD: 0.41; 95% CI, 0.09 to 0.72; p=0.01; I²=11%). NMES protocol varied across studies and requires standardization.

Conclusion

NMES could be considered as a therapeutic strategy to improve glycemic control in populations with physical impairments and/or metabolic disorders.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42020192491.

Is There an Optimal Time of Day for Exercise? A Commentary on When to Exercise for People Living With Type 1 or Type 2 Diabetes

Exercise is a cornerstone of diabetes self-care because of its association with many health benefits. Several studies that have explored the best time of day to exercise to inform clinical recommendations have yielded mixed results. For example, for people with prediabetes or type 2 diabetes, there may be benefits to timing exercise to occur after meals, whereas people with type 1 diabetes may benefit from performing exercise earlier in the day. One common thread is the health benefits of consistent exercise, suggesting that the issue of exercise timing may be secondary to the goal of helping people with diabetes establish an exercise routine that best fits their life.

Physiotherapists’ Perspectives on Type 2 Diabetes Management and as a Primary Condition for Referral to Physiotherapy Services: A Qualitative Descriptive Study

Purpose:

We explored the current and potential role of physiotherapists in the management of people with type 2 diabetes (T2D) and T2D as a primary condition for physiotherapy referral.

Method:

We conducted a qualitative descriptive study. Participants were physiotherapists practicing in community and outpatient settings across Canada. One-on-one telephone interviews were completed to explore provision of physiotherapy care for people with T2D, including current practices and readiness of physiotherapists to provide direct care. We employed thematic analysis for generation of themes from interviews.

Results:

We interviewed 21 participants from eight provinces and territories. Three themes were generated from the data: current approach to T2D management; challenges for physiotherapy integration; and merits of physiotherapy and needed evolution. Participants described that physiotherapists are not part of the healthcare team for T2D management. There is a gap in medical management of T2D that physiotherapy would fill, that is, education and prescription for exercise participation.

Conclusions:

Our findings support a gap in the management of T2D in Canadian healthcare, particularly in reference to physiotherapy. Further, our findings support the need for greater inclusion of physiotherapists for lifestyle counseling with an emphasis on physical activity and exercise for patients at risk of and with T2D to maximize health and improve/maintain function. Studies focusing on accessibility and funding of physiotherapy services are needed to validate these findings.

Acute changes in glucose induced by continuous or intermittent exercise in children and adolescents with type 1 diabetes

Objective

To estimate the rate of change during exercise and during recovery in moderate-continuous exercise (MCE) and high-intensity intermittent exercise (HIIE) in children and adolescents with type 1 diabetes (T1D).

Methods

Participants performed 2 sessions of exercise: thirty minutes of continuous activity on a cycle ergometer (60% of VO_2max) and thirty minutes (60% VO_2max) interspersed with five bouts of maximum intensity lasting ten seconds every five minutes. Capillary blood glucose was measured before and after each test. The glucose rate of change in exercise (RoC_E) was calculated (final blood glucose - onset blood glucose/exercise time), and the glucose rate of change in recovery (RoC_R) (blood glucose 30 minutes after exercise - end of exercise blood glucose/recovery time).

Results

The study included thirty-one participants (aged 13 ± 1.88 years). A lower blood glucose reduction was observed in the HIIE group, as well as better recovery values before, after, and thirty minutes after the test, respectively (333.14 ± 69.53, 226.19 ± 68.05 and 201.77 ± 66.84 versus 211.36 ± 91.03, 155.98 ± 82,68 and 165.76 ± 72.94). Covariance analyses showed a significant difference in glycemic variation between continuous and intermittent protocols immediately after exercise (-2.90 versus -2.08) and during the recovery period (-0.677 versus -0.389).

Conclusion

HIIE led to a lower glucose reduction rate per minute during exercise and better recovery in the first 30 minutes after exercise compared to MCE in children and adolescents with T1D.

Determinants in Tailoring Antidiabetic Therapies: A Personalized Approach

Diabetes has become a pandemic as the number of diabetic people continues to rise globally. Being a heterogeneous disease, it has different manifestations and associated complications in different individuals like diabetic nephropathy, neuropathy, retinopathy, and others. With the advent of science and technology, this era desperately requires increasing the pace of embracing precision medicine and tailoring of drug treatment based on the genetic composition of individuals. It has been previously established that response to antidiabetic drugs, like biguanides, sulfonylureas, dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide 1 (GLP-1) agonists, and others, depending on variations in their transporter genes, metabolizing genes, genes involved in their action, etc. Responsiveness of these drugs also relies on epigenetic factors, including histone modifications, miRNAs, and DNA methylation, as well as environmental factors and the lifestyle of an individual. For precision medicine to make its way into clinical procedures and come into execution, all these factors must be reckoned with. This review provides an insight into several factors oscillating around the idea of precision medicine in type-2 diabetes mellitus.

The Effects of COVID-19 Lockdown on Glycaemic Control and Lipid Profile in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis

The impact of the COVID-19 lockdown on glycaemic control and other metabolic parameters in patients with type 2 diabetes is still evolving. Aim: This systematic review and meta-analysis aims to examine the effects of COVID-19 lockdown on glycaemic control and lipid profile in patients with type 2 diabetes. Methods: The PRISMA framework was the method used to conduct the systematic review and meta-analysis, and the search strategy was based on the population, intervention, control and outcome (PICO) model. The Health Sciences Research databases was accessed via EBSCO-host, and EMBASE were searched for relevant articles. Searches were conducted from inception of the databases until 17 September 2021. Results: The results identified three distinct areas: glycaemic control, lipid parameters and body mass index. It was found that COVID-19 lockdown led to a significant (p < 0.01) increase in the levels of glycated haemoglobin (%) compared with pre-COVID group (gp) with a mean difference of 0.34 (95% CI: 0.30, 0.38). Eleven studies contributed to the data for glycated haemoglobin analysis with a total of 16,895 participants (post-COVID-19 lockdown gp, n = 8417; pre-COVID gp, n = 8478). The meta-analysis of fasting plasma glucose (mg/dL) also showed a significant (p < 0.05) increase in levels of post-COVID-19 lockdown gp compared with pre-COVID gp, with a mean difference of 7.19 (95% CI: 5.28, 9.10). Six studies contributed to fasting plasma glucose analysis involving a total of 2327 participants (post-COVID-19 lockdown, n = 1159; pre-COVID gp, n = 1168). The body mass index (BMI) (kg/m²) analysis also demonstrated that post-COVID-19 lockdown gp had a significantly (p < 0.05) higher BMI than the pre-COVID gp with a mean difference of 1.13 (95% CI: 0.99; 1.28), involving six studies and a total of 2363 participants (post-COVID-19 lockdown gp, n = 1186; pre-COVID gp, n = 1177). There were significantly (p < 0.05) lower levels of total cholesterol (mmol/L), triglyceride (mmol/L) and LDL cholesterol (mmol/L), and higher levels of HDL cholesterol (mg/dL) in the post-COVID-19 lockdown gp compared with pre-COVID gp, although these results were not consistent following sensitivity analysis. Conclusion: The findings of the systematic review and meta-analysis have demonstrated that COVID-19 lockdown resulted in a significant increase (p < 0.05) in the levels of glycated haemoglobin, fasting glucose and body mass index in patients with type 2 diabetes. In contrast, the effect of the lockdown on lipid parameters, including total cholesterol, triglycerides, LDL and HDL cholesterol was not consistent.

The expanding roles of neuronal nitric oxide synthase (NOS1)

The nitric oxide synthases (NOS; EC 1.14.13.39) use L-arginine as a substrate to produce nitric oxide (NO) as a by-product in the tissue microenvironment. NOS1 represents the predominant NO-producing enzyme highly enriched in the brain and known to mediate multiple functions, ranging from learning and memory development to maintaining synaptic plasticity and neuronal development, Alzheimer's disease (AD), psychiatric disorders and behavioral deficits. However, accumulating evidence indicate both canonical and non-canonical roles of NOS1-derived NO in several other tissues and chronic diseases. A better understanding of NOS1-derived NO signaling, and identification and characterization of NO-metabolites in non-neuronal tissues could become useful in diagnosis and prognosis of diseases associated with NOS1 expression. Continued investigation on the roles of NOS1, therefore, will synthesize new knowledge and aid in the discovery of small molecules which could be used to titrate the activities of NOS1-derived NO signaling and NO-metabolites. Here, we address the significance of NOS1 and its byproduct NO in modifying pathophysiological events, which could be beneficial in understanding both the disease mechanisms and therapeutics.

Should weight-bearing activity be reduced during healing of plantar diabetic foot ulcers, even when using appropriate offloading devices?

Physical activity is an essential part of general health and diabetes management. However, recommending weight-bearing physical activity for people with plantar diabetic foot ulcers is controversial, even when gold standard offloading devices are used, as it is commonly thought to delay healing. We aimed to narratively review relevant studies investigating the relationship between plantar diabetic foot ulcer healing and weight-bearing activity, plantar pressure and device adherence. We defined relevant studies as those from two systematic reviews, along with those identified since using a similar updated Pubmed search strategy. We identified six studies. One study found that more daily steps were associated with worse ulcer healing, three found no significant association between steps and ulcer healing, and in two others the association was unclear. Thus, there is weak evidence for an inverse relationship between weight-bearing physical activity and plantar ulcer healing while utilizing offloading devices. We propose a Diabetic foot Offloading and Activity framework to guide future research to find the optimal balance between the positive and negative effects of weight-bearing activity in the context of foot ulcers. We hope such future studies will shed more conclusive light on the impact of weight-bearing activity on healing of plantar diabetic foot ulcers.

The Combined Effect of Neuromuscular Electrical Stimulation and Insulin Therapy on Glycated Hemoglobin Concentrations, Lipid Profiles and Hemodynamic Parameters in Patients with Type-2-Diabetes and Hemiplegia Related to Ischemic Stroke: A Pilot Study

Type-2-diabetes mellitus (T2DM) is a global problem of medical, social and economic consequences. Physical activity is a vital therapy in patients with T2DM, but some of them cannot exercise for various reasons. The purpose of our pilot study was to determine whether a combination of neuromuscular electrostimulation (NMES) and insulin therapy could improve the management of T2DM patients with hemiplegia caused by an ischemic stroke. Fifteen immobile patients with T2DM on insulin therapy were enrolled in the study. NMES was applied to their lower limbs for 60 min, 5 days a week, over a period of 12 weeks. The intervention caused statistically significant reductions in the blood concentrations of glycated hemoglobin, total cholesterol and low-density cholesterol in the participants. Furthermore, systolic and diastolic blood pressure levels were significantly lower. More randomized clinical trials are needed to accurately measure the effect of NMES on T2DM treatment and to determine whether it can be an alternative for physical activity for immobile patients with T2DM.

Exercise as a Therapeutic Intervention in Gestational Diabetes Mellitus

Gestational Diabetes Mellitus (GDM) is defined as any degree of glucose intolerance with onset or first recognition during pregnancy. Regular exercise is important for a healthy pregnancy and can lower the risk of developing GDM. For women with GDM, exercise is safe and can affect the pregnancy outcomes beneficially. A single exercise bout increases skeletal muscle glucose uptake, minimizing hyperglycemia. Regular exercise training promotes mitochondrial biogenesis, improves oxidative capacity, enhances insulin sensitivity and vascular function, and reduces systemic inflammation. Exercise may also aid in lowering the insulin dose in insulin-treated pregnant women. Despite these benefits, women with GDM are usually inactive or have poor participation in exercise training. Attractive individualized exercise programs that will increase adherence and result in optimal maternal and offspring benefits are needed. However, as women with GDM have a unique physiology, more attention is required during exercise prescription. This review (i) summarizes the cardiovascular and metabolic adaptations due to pregnancy and outlines the mechanisms through which exercise can improve glycemic control and overall health in insulin resistance states, (ii) presents the pathophysiological alterations induced by GDM that affect exercise responses, and (iii) highlights cardinal points of an exercise program for women with GDM.

Antidiabetic Effects of Physical Activity: How It Helps to Control Type 2 Diabetes

Despite the improvements in clinical care of the patients, research updates, and public health interventions, there is still an increase in the prevalence, incidence, and mortality because of diabetes mellitus (DM). DM is a public health problem in both developed and developing countries. It has increased alarmingly, putting this disease in the dimension of an epidemic. Diabetes is associated with several complications which increase the risk of many serious health problems on the other side. Therefore, this review was aimed to discuss the antidiabetic effects of physical activity (PA) on type 2 DM (T2DM) by summarizing the significant studies on this topic. This review found that several studies have recommended the utilization of PA for the effective management of T2DM. PA is a non-pharmacologic therapy which is a significant strategy for the management of T2DM and is an appropriate lifestyle modification approach to be practiced by these patients. The studies showed that PA has antidiabetic effects which are evidenced by its substantial role in improving the blood glucose (BG) levels of the individuals with T2DM where it helps them to control their levels of glucose in the blood. It plays a significant role in glycemic control of this disease by lowering the BG levels through possible mechanisms such as decreasing insulin resistance, increasing production of glucose transporter type 4 (GLUT-4), lowering visceral adipose tissue (VAT), increasing pancreatic β-cell functions, using glucose for energy, and so on. In turn, the controlled glycemia helps to prevent the complications associated with uncontrolled T2DM and this would further improve the overall health of the patients and the burden on the health professionals as well. Finally, this review concludes that PA is the cornerstone in the management of T2DM. It also suggests that more attention is needed to its significance in the prevention, glycemic control, and its role in the management of the morbidity and mortality associated with T2DM. Practical PA recommendations and suggestions for the future direction of research in this area are also provided.

Effect of Foot Exercise and Care on Peripheral Vascular Status in Patients with Diabetes Mellitus

Introduction: Diabetes mellitus is a cause of health problems which occurs in most countries. Approximately 13 - 15% of all patients with diabetes mellitus will experience peripheral circulatory disorders. Foot exercise and foot care are interventions that can be implemented to prevent foot ulcers.Methods: This study employed a pre-post-test quasi-experimental design with a control group. The sample consisted of 94 patients with diabetes mellitus who were assigned to the intervention group (n=47) and the control group (n=47) respectively. Consecutive sampling was used to recruit the samples. The instruments used to collect the data included 10-g monofilament for the diabetic neuropathy test, a HbA1c test and a sphygmomanometer. The collected data was analyzed using a paired t-test.Results: The results of this study showed there to be significant effects from foot exercise and foot care on the HbA1c test, in relation to the frequency of the dorsalis pedis artery and diabetic neuropathy with a significance value of 0.00 (p<0.05). However, in the ankle-brachial index measurement, there were no significant differences between the intervention and control groups with a significance value of 0.26 (p>0.05).Conclusion: Foot exercise and foot care can be one of the independent nursing interventions used to prevent the complications of diabetes mellitus, as they have been proven to improve the peripheral vascular status of patients with diabetes mellitus by 70-80%.

Effects of a 12-week moderate-intensity exercise training on blood glucose response in patients with type 2 diabetes: A prospective longitudinal study

BACKGROUND

The blood glucose response to moderate-intensity exercise remains unclear for patients with type 2 diabetes (T2DM). In addition, little is known about determinants of blood glucose response to a 12-week moderate-intensity exercise training. Therefore, this study aimed to explore trends in blood glucose in response to a 12-week moderate-intensity exercise training in patients with T2DM and to explore the predictors of post-exercise blood glucose (PEBG) and exercise-induced glucose response (EIGR).

METHODS

A prospective longitudinal study was conducted. Of the 66 participants with T2DM recruited from outpatient clinics of a medical center, 20 were eligible to enroll in a 12-week moderate-intensity exercise training. Participants were randomly assigned to 1 of 3 exercise times (morning, afternoon, or evening). Blood glucose were measured pre- and post-exercise. The EIGR was calculated by subtracting the PEBG from the before-exercise blood glucose (BEBG). Generalized estimating equations were used to examine the trends and predictors of PEBG and EIGR.

RESULTS

The BEBG declined progressively (β = -1.69, P < .001); while the PEBG (β = -0.18, P = .08) remained stable over time during the 12-week exercise training. Higher BEBG predicted higher (β = 0.53, P < .001) PEBG. Higher baseline maximum oxygen uptake (VO2max) contributed to a larger magnitude of EIGR; higher HgbA1c and BEBG predicted higher EIGR (β = 0.27, P = .02; β = 0.45, P < .001); afternoon or evening exercise predicted lower (β = -13.2, P = .04; β = -5.96, P = .005) EIGR than did morning exercise.

CONCLUSIONS

A 12-week moderate-intensity exercise training appears safe for patients with T2DM. Time of day for exercise, baseline VO2max, and baseline metabolic control may influence the impact of exercise for individuals with T2DM. These findings provide considerations for design of optimal exercise training for T2DM patients.

Type 1 diabetes does not impair the physical capacity of non-sedentary adolescents

BACKGROUND

Type 1 diabetes patients have a higher risk of developing hypoglycemia or hyperglycemia during physical activity, which may compromise their safety during exercise but results regarding the exercise capacity of patients with type 1 DM when compared to control subjects have been contradictory.

AIM

To evaluate if type 1 diabetes affects the capacity of adolescents to exercise.

METHODS

The study enrolled 37 adolescents in stage 2-4 of the Tanner scale, aged from 10 to 14 years, 21 with type 1 diabetes and 16 without any chronic diseases. All subjects performed an incremental submaximal exercise test in a cycle ergometer. At the end of every test stage, glycemia and blood lactate levels were measured. During the test, heart rate was monitored and the Borg rating of perceived exertion (RPE) was used to assess fatigue.

RESULTS

The two groups displayed no significant differences in anthropometric variables. The response to exercise, as evaluated by Borg RPE (p = 0.829), maximum oxygen uptake (VO2max) (p = 0.977), heart rate (p = 0.998), maximum load (p = 0.977), absolute load at lactate threshold (p = 0.377) and relative load at lactate threshold (p = 0.282), was also similar between the control and the type 1 diabetes group. Finally, there were no significant correlations between HbA1c levels, VO2max, duration of disease and pre-test glycemia levels.

CONCLUSIONS

We detected no significant differences in lactate threshold, VO2max and heart rate during exercise between healthy adolescents and non-sedentary adolescents with type I diabetes, indicating that both groups had similar physical fitness and, therefore, that type 1 diabetes is not an obstacle for physical activity. This study was approved by the ethical committee of the Hospital Israelita Albert Einstein (Ethical Committee Number: 53638416.9.0000.0071) and free and informed consent was obtained from all participants and their legal representatives.

High Intensity Aerobic and Resistance Exercise Can Improve Glucose Tolerance in Persons With Multiple Sclerosis: A Randomized Controlled Trial

INTRODUCTION

The prevalence of impaired glucose tolerance (IGT) is higher in persons with multiple sclerosis (MS) compared to healthy controls, indicating metabolic deficits that may increase comorbidity. In other populations, IGT can, at least partly, be reversed by intense physical exercise, but this is never investigated before in MS.

AIM

To investigate the effect of high intensity aerobic and resistance training on glucose tolerance and skeletal muscle GLUT4 content in MS.

METHODS

Thirty-four persons with MS (aged 45 ± 3 years, EDSS 2.5 ± 1.07) were randomized into three groups, including a (1) sedentary control group (SED, n = 11), (2) 12-week high intensity interval plus resistance training group (HITR, n = 12), or (3) 12-week high intensity continuous aerobic training plus resistance training group (HCTR, n = 11). Before and after 12 weeks, glucose tolerance and skeletal muscle GLUT4 content were determined by an oral glucose tolerance test and analysis of a m.vastus lateralis biopsy, respectively.

RESULTS

There were no significant changes for subjects of SED. From pre- to post-intervention, total area under the glucose curve (tAUC) decreased significantly in both HITR (-6.9 ± 6.2%) and HCTR (-11.0 ± 7.7%) (P < 0.05). Insulin tAUC decreased (-12.3 ± 14.7%) within HCTR and muscle GLUT4 content increased (+6.6 ± 4.5%) in HITR.

CONCLUSION

Twelve weeks of high intensity aerobic exercise in combination with resistance training improved glucose tolerance in persons with MS.

Impact of a walking program of 10,000 steps per day and dietary counseling on health-related quality of life, energy expenditure and anthropometric parameters in obese subjects

PURPOSE

The aim of this pilot study was to assess the impact of a physical activity program of walking 10,000 steps per day along with monthly dietary counseling on the body composition, biological parameters, resting energy expenditure (REE) and health-related quality of life (HRQoL) of obese individuals.

METHODS

Thirty-five obese adults (26 women; age: 39.2 ± 13.4 years, body mass, BM: 104.1 ± 18.7 kg and body mass index, BMI: 38.3 ± 6.6 kg m^-2) followed a walking program (instructions were provided so that the participants increase their walking distance by 1000 steps each week, until to perform at least 10,000 steps per day) and received qualitative dietary advice (cookbook presenting numerous recipes with low calories and dietary advices was provided) for 6 months. Before and after the intervention, anthropometric (BM, BMI, waist and hip circumferences, fat mass: FM and lean body mass: LBM) and biological data (total cholesterol, high-density lipoprotein, low-density lipoprotein, triglyceride and glucose concentrations), REE and HRQoL (including eight dimensions and two summaries) were assessed.

RESULTS

After the intervention, BM (difference: 3.8 kg or 3.7 %), BMI (difference: 1.4 kg m^-2 or 3.7 %), hip circumference (difference: 4.6 cm or 4.3 %), FM in kg (difference: 4.0 kg or 8.9 %) and FM in percentage of BM (difference: 1.6 kg or 6.1 %) were significantly decreased, whereas number of steps (difference: 7579 steps or 135 %), LBM in percentage of BM (difference: 2.6 kg or 4.5 %) and REE (difference: 78 kcal d^-1 or 4.8 %) were significantly increased (p < 0.05). Moreover, two HRQoL subdimension scores (physical functioning and physical component summary; increase by 15.3 and 4.6, respectively, p < 0.05) and anxiety (reduction by 1.2, p < 0.05) were also significantly improved. Conversely, the biological data showed no significant change (p > 0.05).

CONCLUSION

Walking 10,000 steps per day in association with dietary counseling improved anthropometric data, REE, the physical domains of HRQoL and anxiety in obese adults.

Effect of Low Frequency Neuromuscular Electrical Stimulation on Glucose Profile of Persons with Type 2 Diabetes: A Pilot Study

The purpose of this study was to examine the effect of low-frequency neuromuscular electrical stimulation (NMES) on glucose profile in persons with type 2 diabetes mellitus (T2DM). Eight persons with T2DM (41 to 65 years) completed a glucose tolerance test with and without NMES delivered to the knee extensors for a 1-hour period at 8 Hz. Three blood samples were collected: at rest, and then 60 and 120 minutes after consumption of a glucose load on the NMES and control days. In NMES groups glucose concentrations were significantly lower (P<0.01) than in the control conditions. Moreover, a significant positive correlation (r=0.9, P<0.01) was obtained between the intensity of stimulation and changes in blood glucose. Our results suggest that low-frequency stimulation seem suitable to induce enhance glucose uptake in persons with T2DM. Moreover, the intensity of stimulation reflecting the motor contraction should be considered during NMES procedure.

Neuromuscular electrostimulation and insulin sensitivity in patients with type 2 diabetes: the ELECTRODIAB pilot study

AIM

Physical activity (PA) improves insulin sensitivity and is particularly important for type 2 diabetes (T2D) management; however, patient adherence is poor. Neuromuscular electrostimulation (NMES) is widely used for rehabilitation issues, but the metabolic impact of provoked involuntary muscular contractions has never been investigated.

MATERIALS AND METHODS

ELECTRODIAB is a prospective, bi-centric, and 4-week-long pilot study that enrolled 18 patients with T2D who did not require insulin treatment. Insulin sensitivity was evaluated by euglycemic hyperinsulinemic clamp before and after (1) a single NMES session and (2) a week of daily NMES training. Energy expenditure (EE) at baseline and during NMES was evaluated by indirect calorimetry. Dietary and background PA were monitored to avoid bias.

RESULTS

After a single session (T1) or a week (T2) of NMES training, insulin sensitivity (M value) increased by 9.3 ± 38.2 % (ns) and 24.9 ± 35.8 % (p = 0.009), respectively, compared with the baseline (T0). Insulin sensitivity increased up to 46.2 ± 33.8 % (p = 0.002) at T2 in the more insulin-resistant subjects (baseline M value ≤4 mg/Kg/min, n = 10). The NMES session-generated EE was 1.42 ± 9.27 kcal/h, which was not significantly increased from the baseline.

CONCLUSIONS

Insulin sensitivity was significantly improved in patients with T2D after 1 week of daily NMES training, with very low EE. NMES could be an alternative to conventional PA, but the putative mechanisms of action must still be investigated.

The role of TNF-α G-308A promoter polymorphism in glycemic control in Type 2 diabetes patients

BACKGROUND

TNF-α polymorphisms were shown to be associated with insulin resistance and diabetes development and complications.

AIM

To investigate the association between glycemic control in Type 2 diabetes patients and TNF-α G-308A single nucleotide polymorphism (SNP).

METHODS

This was a cross-sectional observational study, where diabetes patients from both genders (170 male and 185 female) were enrolled in the study. Patients were divided into two groups: good glycemic control (n = 158) and poor glycemic control (n = 197). Genotyping of TNF-α G-308A SNP was carried out using restriction fragment length polymorphisms-polymerase chain reaction.

RESULTS

The results showed that TNF-α G-308A SNP is strongly associated with glycemic control in type 2 diabetes patients. Patients with the AA and AG genotypes had better glycemic control than those with GG genotype (P < 0.01). Other parameters that impacted glycemic control include duration of the disease (P < 0.01) and response to insulin therapy (P < 0.01). However, no contribution for gender or statins use to glycemic control was observed (P > 0.05).

CONCLUSION

TNF-α G-308A SNP might modulate glycemic control among type 2 diabetes patients.

Physical activity and type 2 diabetes. Recommandations of the SFD (Francophone Diabetes Society) diabetes and physical activity working group

Although regular physical activity is an integral part of T2D management, few diabetic patients have a sufficient level of physical activity. However over the past decade or so, the beneficial effects of regular physical activity have been well demonstrated, both in T2D prevention (50% reduction in the incidence of T2D in subjects with high metabolic risk) as well as T2D management for the improvement of glycaemic control (mean 0.7% improvement of HbA1c) and the reduction of T2D-related comorbidities (improvement in blood pressure values and lipid profile, decrease in insulin resistance). Physical activity has both acute effects (effects of one exercise session) and more prolonged effects of exercise when it is repeated on a regular basis (training effect). In addition, the physical activity recommendations have been extended to a wide range of physical activities (by combining both endurance and muscle strengthening exercises), thus varying the physical activity practiced according to the patient's available time, practice sites, preferences and interests. Following a pathophysiology review, the effects of physical activity will be discussed and presented in terms of evidence-based medicine. The recommendations will be defined and practical prescribing information will be suggested, while taking into account that clinicians are concerned with answering questions regarding how, where and with whom: how can patients be motivated to practice a physical activity over the long-term? And how can qualified exercise trainers and appropriate practice settings be found?

Organ-based response to exercise in type 1 diabetes

While significant research has clearly identified sedentary behavior as a risk factor for type 2 diabetes and its subsequent complications, the concept that inactivity could be linked to the complications associated with type 1 diabetes (T1D) remains underappreciated. This paper summarizes the known effects of exercise on T1D at the tissue level and focuses on the pancreas, bone, the cardiovascular system, the kidneys, skeletal muscle, and nerves. When possible, the molecular mechanisms underlying the benefits of exercise for T1D are elucidated. The general benefits of increased activity on health and the barriers to increased exercise specific to people with T1D are discussed.

Comparison of glucose monitoring methods during steady-state exercise in women

Data from Continuous Glucose Monitoring (CGM) systems may help improve overall daily glycemia; however, the accuracy of CGM during exercise remains questionable. The objective of this single group experimental study was to compare CGM-estimated values to venous plasma glucose (VPG) and capillary plasma glucose (CPG) during steady-state exercise. Twelve recreationally active females without diabetes (aged 21.8 ± 2.4 years), from Central Washington University completed the study. CGM is used by individuals with diabetes, however the purpose of this study was to first validate the use of this device during exercise for anyone. Data were collected between November 2009 and April 2010. Participants performed two identical 45-min steady-state cycling trials (~60% P_max) on non-consecutive days. Glucose concentrations (CGM-estimated, VPG, and CPG values) were measured every 5 min. Two carbohydrate gel supplements along with 360 mL of water were consumed 15 min into exercise. A product-moment correlation was used to assess the relationship and a Bland-Altman analysis determined error between the three glucose measurement methods. It was found that the CGM system overestimated mean VPG (mean absolute difference 17.4 mg/dL (0.97 mmol/L)) and mean CPG (mean absolute difference 15.5 mg/dL (0.86 mmol/L)). Bland-Altman analysis displayed wide limits of agreement (95% confidence interval) of 44.3 mg/dL (2.46 mmol/L) (VPG compared with CGM) and 41.2 mg/dL (2.29 mmol/L) (CPG compared with CGM). Results from the current study support that data from CGM did not meet accuracy standards from the 15197 International Organization for Standardization (ISO).

Comparison of activity level among patients with chronic liver disease

PURPOSE

To determine whether self-reported maximal and daily activity levels are impaired among patients with nonalcoholic fatty liver disease (NAFLD), hepatitis C (HCV) and hepatitis B (HBV).

METHODS

Clinicodemographic, diagnostic, self-report and standard laboratory data were obtained. Univariate, multivariate and regression analyses were performed comparing group maximal (Maximum Activity Score [MAS]) and daily activity scores (Adjusted Activity Score [AAS]), adjusted for age and gender.

RESULTS

Two hundred twenty-two patients completed activity-level self-reports (mean age [52.4 ± 10.0 years], BMI [28.3 ± 6.58], 31.2% NAFLD, 48.3% HCV, 20.3% HBV). On multivariate analysis, significantly higher MAS (p < 0.05) and AAS in HBV patients correlated with absence of cirrhosis, younger age, male gender (higher MAS) and lower BMI (higher AAS). Lowest activity levels were found primarily in obese patients (p < 0.009). Compared with population norms, NAFLD and HCV cohorts scored mildly disabled on MAS; the HBV cohort scored low normal. Mild disability on AAS was observed in patients with HBV; moderate disability in those with NAFLD, HCV.

CONCLUSIONS

All groups had significantly lower activity levels than population norms. Nonobese patients showed significantly less disability than obese patients. Patients with NAFLD and HCV are likely to have lower levels than those with HBV without cirrhosis. This presents an additional risk factor for disability and mortality.

IMPLICATIONS FOR REHABILITATION

• Hepatitis B (HBV), hepatitis C (HCV), and nonalcoholic fatty liver disease (NAFLD) patients had significantly lower activity levels than expected for their age and gender, as measured by the Human Activity Profile (HAP). • Overweight and normal weight chronic liver disease (CLD) patients showed significantly less disability than obese chronic liver disease patients. • Patients with NAFLD and HCV are likely to participate in low levels of activity that require fewer metabolic equivalents for completion, adding an additional risk factor for disability and mortality. • Targeting low activity level in CLD patients, and decreasing BMI below the obesity threshold, may reduce disability and risk of mortality.

Combined insulin treatment and intense exercise training improved basal cardiac function and Ca2+-cycling proteins expression in type 1 diabetic rats

This study investigated the effects of 8 weeks of intense exercise training combined with insulin treatment on the Ca2+-cycling protein complex expression and their functional consequences on cardiac function in type 1 diabetic rat hearts. Diabetic Wistar rats were randomly assigned into the following groups: received no treatment, insulin-treated diabetic, trained diabetic, and trained insulin-treated diabetic. A control group was also included. Insulin treatment and (or) treadmill intense exercise training were conducted over 8 weeks. Basal cardiac function was evaluated by Langendorff technique. Cardiac expression of the main Ca2+-cycling proteins (RyR2, FKBP 12.6, SERCA2, PLB, NCX1) was assessed by Western blot. Diabetes altered basal cardiac function (±dP/dt) and decrease the expression of the main Ca2+-cycling proteins expression: RyR2, SERCA2, and NCX1 (p < 0.05). Whereas combined treatment was not able to normalize –dP/dt, it succeeded to normalize +dP/dt of diabetic rats (p < 0.05). Moreover, both insulin and intense exercise training, applied solely, increased the expression of the Ca2+-cycling proteins: RyR2, SERCA2, PLB. and NCX1 (p < 0.05). But this effect was higher when the 2 treatments were combined. These data are the first to show that combined insulin treatment and intense exercise training during diabetes synergistically act on the expression of the main Ca2+-cycling proteins, providing insights into mechanisms by which the dual treatment during diabetes improves cardiac function.

Pushing out the limits of electrical stimulation. A case study in the aggressive use of an alternative to voluntary exercise

Recent advances in neuromuscular electrical stimulation (NMES) suggest that sophisticated techniques can exercise and train people aerobically. However, the limits of this exercise modality would be of interest to sportspeople, trainers and rehabilitation experts. Additionally, there are physical and other barriers which prevent many from undertaking aggressive voluntary exercise. Maximum voluntary and peak NMES efforts were assessed for 1) maximal heart rate and oxygen consumption, 2) excess postexercise oxygen consumption (EPOC), 3) lactate and 4) time-to-fatigue while exercising at 65% of predicted maximal heart rate (maximum voluntary versus peak NMES efforts). Heart rates: 195 bpm and 194 bpm; Oxygen consumption: 52 ml/kg/min and 39 ml/kg/min. EPOC: 110.5 kcal and 96.5 kcal; Lactate: 15.0 mmol/l and 15.3 mmol/l; Time-to-fatigue: 4 h and over 6 h. Sophisticated NMES compares well to voluntary exercise with potential applications for sportspeople and some who cannot exercise due to disease or injury.

Insulin therapy and exercise

Medical nutrition therapy and physical exercise are the cornerstones of the diabetes management. Patients with type 1 DM always need exogenous insulin administration, recently available in the form of insulin analogs. In type 2 DM, characterized by increased insulin resistance and progressive decline of the beta-cell function, various antidiabetic medications are used. Most of the subjects with type 2 DM will finally need insulin. The main site of insulin action is the skeletal muscle, while the liver is the main site of glucose storage in the form of glycogen. With the modern diabetes therapies it is possible to rapidly reach and maintain normoglycemia in both types of DM but with the cost of higher incidence of hypoglycemia, especially related to exercise. Regular physical exercise causes a lot of beneficial effects in healthy as well as diabetic subjects of all age groups. In type 1 DM physical exercise is a fundamental element for both physical and mental development. In type 2 DM it has a main role in diabetes control. The increased hepatic glucose production and the increased muscular glucose uptake during exercise are closely interrelated in all exercise intensities. In diabetes mellitus there is a disturbed energy substrate use during exercise leading to either hypo- or hyperglycemia. The influence of low or moderate intensity aerobic exercise on diabetes control has been well studied. The inappropriately high insulinemia combined with the low glucose levels can lead to severe hypoglycemia if proper measures are not taken. Prolonged exercise can also predispose to decreased glucose counter regulation. It is better for the type 1 diabetic subject to postpone the exercise session in very high (>300 mg/dl) or very low (<70 mg/dl) BG levels. Every insulin treated subject is recommended to be checked for any existing diabetic complication before the start of every exercise program. Glucose measurement with glucose meters or sometimes with Continuous Glucose Monitoring System (CGMS) must be made before, during and most importantly after the end of the exercise session. It is recommended either to reduce or suspend the previous insulin dose depending on the insulin regime or to receive extra carbohydrates before, during or after the exercise session or both. Subjects with type 1 DM may participate at almost all the competitive sports if precautions are taken. These measures must be individualized and readjusted, even empirically. In very high intensity exercise (about 80% of VO(2 max)) or when high intensity exercise follows a low intensity one, there is a tendency of the BG to increase due to excessive circulating catecholamines necessitating postexercise short acting insulin. In anaerobic or resistance exercise lactic acid is produced. This exercise type is recommended for people in whom aerobic exercise is contraindicated. These two exercise types can be combined. The incidence of hypoglycemia or hyperglycemia in specific forms of resistance exercise as well as the appropriate insulin dose adjustment are not well studied. In conclusion all exercise types are beneficial for both types of diabetes.

Effects of a home-based aerobic exercise programme in children with type 1 diabetes mellitus

AIMS

To explore the effects of exercise programme on glycosylated haemoglobin and peak oxygen uptake in children and adolescents with type 1 diabetes mellitus.

BACKGROUND

Regular exercise has been shown to be effective in blood glucose control, which includes improving glucose tolerance and insulin sensitivity, decreasing glycosylated haemoglobin levels and improving cardiorespiratory fitness.

DESIGN

Quasi-experimental design with a twelve-week home-based aerobic exercise programme.

METHOD

Twenty-eight participants completed the study: 12 in the home-based exercise group, 11 in the non-exercise control group and five in the self-directed exercise group. A mixed model was used to capture longitudinal change in glycosylated haemoglobin levels.

RESULTS

The home-based aerobic exercise group showed no significant effect on glycemic control and peak oxygen uptake in this study across assessment times. However, a group difference in glycosylated haemoglobin levels at the nine-month follow-up was significant (general linear model: F = 4.06, p = 0.03). A Bonferroni test indicated that glycosylated haemoglobin levels in the home-based exercise group were higher than in the self-directed exercise group (p < 0.05) and higher in the control group than in the self-directed exercise group (p < 0.05) at the nine-month follow-up. Home-based aerobic exercise showed no significant effect on peak oxygen uptake in this study.

CONCLUSIONS

A three-month home-based aerobic exercise programme has no significant effect on glycosylated haemoglobin and peak oxygen uptake levels in children with type 1 diabetes mellitus.

RELEVANCE TO CLINICAL PRACTICE

Our exercise programme has designed that children can practice exercise at home and is a viable component of self-care intervention to improve patient's self-care skill and diabetes care control. However, how to encourage patients to adhere the exercise programme is a challenge for health care providers.

Isomaltulose Improves Postexercise Glycemia by Reducing CHO Oxidation in T1DM

PURPOSE

individuals with type 1 diabetes mellitus (T1DM) are encouraged to consume CHO to prevent hypoglycemia during or after exercise. However, the research comparing specific types of CHO is limited. This study compared the alterations in metabolism and fuel oxidation in response to running after preexercise ingestion of isomaltulose or dextrose in T1DM.

METHODS

after preliminary testing, on two occasions, eight T1DM individuals consumed 75 g of either dextrose (DEX; GI = 96) or isomaltulose (ISO; GI = 32), 2 h before performing 45 min of treadmill running at 80% ± 1% VO(2peak). Blood glucose (BG) was measured for 2 h before and 3 h after exercise. Cardiorespiratory parameters were collected at rest and during exercise. Data (mean ± SEM) were analyzed using repeated-measures ANOVA.

RESULTS

there was a smaller increase in BG in the preexercise period under ISO with peak BG occurring at 120 min after ingestion compared with 90 min under DEX (Δ+4.5 ± 0.4 vs Δ+9.1 ± 0.6 mmol·L, P < 0.01). During the final 10 min of exercise, there were lower CHO (ISO 2.85 ± 0.07 vs DEX 3.18 ± 0.08 g·min, P < 0.05) and greater lipid oxidation rates (ISO 0.33 ± 0.03 vs DEX 0.20 ± 0.03 g·min, P < 0.05) under ISO. After exercise, ISO BG was lower than DEX for the entire 180-min period, with BG area under the curve and mean BG concentrations being 21% ± 3% and 3.0 ± 0.4 mmol·L lower, respectively (P < 0.05).

CONCLUSIONS

consumption of ISO improves BG responses during and after exercise through reduced CHO and improved lipid oxidation during the later stages of exercise.

Exercise in the management of type 2 diabetes mellitus: what are the benefits and how does it work?

In this article, we examine the results from meta-analyses of studies that have focused on the effects of supervised exercise in patients with established type 2 diabetes mellitus. Exercise has been clearly demonstrated to have benefits on blood glucose control (average reduction of glycated hemoglobin, 0.6%) and cardiovascular risk factors. These benefits are observed independently of any change in body mass index and fat mass, and are also seen in older populations. Multiple mechanisms are involved, and the improved insulin-sensitizing effect of exercise training is not restricted to muscle but extends to hepatic and adipose tissue. However, while the benefits of exercise in type 2 diabetes management are undisputable, it is not as easy to draw correlations between clinical benefit and the amount of physical activity included in daily life. Recent studies have shown encouraging results with moderate increases in physical activity, which are feasible for most patients and are sufficient to induce sustained positive changes for 2 years. Thus, the benefits of structured and supervised exercise in patients with type 2 diabetes have been consistently demonstrated. Currently, the primary challenge is to determine how long-term increased physical activity can be durably implemented in a patient's daily life.

Intense exercise training induces adaptation in expression and responsiveness of cardiac β-adrenoceptors in diabetic rats

Background

Informations about the effects of intense exercise training on diabetes-induced myocardial dysfunctions are lacking. We have examined the effects of intense exercise training on the cardiac function of diabetic rats, especially focusing on the Langendorff β-adrenergic responsiveness and on the β-adrenoceptors protein expression.

Methods

Control or Streptozotocin induced-diabetic male Wistar rats were randomly assigned to sedentary or trained groups. The training program consisted of 8 weeks running on a treadmill (10° incline, up to 25 m/min, 60 min/day) and was considered to be intense for diabetic rats.

Results

This intense exercise training amplified the in vivo diabetes-induced bradycardia. It had no effect on Langendorff basal cardiac contraction and relaxation performances in control and diabetic rats. In diabetic rats, it accentuated the Langendorff reduced responsiveness to β-adrenergic stimulation. It did not blunt the diabetes-induced decrease of β1-adrenoceptors protein expression, displayed a significant decrease in the β2-adrenoceptors protein expression and normalized the β3-adrenoceptors protein expression.

Conclusions

Intense exercise training accentuated the decrease in the myocardial responsiveness to β-adrenergic stimulation induced by diabetes. This defect stems principally from the β2-adrenoceptors protein expression reduction. Thus, these results demonstrate that intense exercise training induces specific effects on the β-adrenergic system in diabetes.

Effects of exercise training combined with insulin treatment on cardiac NOS1 signaling pathways in type 1 diabetic rats

This study examined the effects of a dual treatment combining insulin treatment and exercise training on basal cardiac function and signaling pathways involving β3-AR, NOS1, and RyR2 in type 1 diabetic rats. Male Wistar rats were assigned into a diabetic group receiving no treatment (D), an insulin-treated diabetic (Ins), a trained diabetic (TD), and a trained insulin-treated diabetic (TIns) group. Control group (C) was included in order to confirm the deleterious effects of diabetes. Insulin treatment and/or treadmill exercise training were conducted for 8 weeks. Basal cardiac function was evaluated by Langendorff technique. Cardiac protein expression of β3-AR, NOS1, and RyR2 was assessed using Western blots. Diabetes induced a decrease of both basal diastolic and systolic (±dP/dt) cardiac function (P < 0.05). Moreover, diabetes was associated with an increase of β3-AR and NOS1 and a decrease of RyR2 expression (P < 0.05). Although combined treatment was not able to normalize -dP/dt, it succeeded to normalize +dP/dt of diabetic rats. Combined treatment led to an overexpression of RyR2. Effects of this combined treatment on +dP/dt and RyR2 were greater than the effects of insulin and exercise training, applied solely. Treatments, applied solely or in combination, resulted in a complete normalization of β3-AR and in a down-regulation of NOS1 because this protein expression in all treated diabetic rats became lower than control values (P < 0.01). Our study shows that unlike single treatments, dual treatment combining insulin treatment and exercise training was able to normalize basal systolic function of diabetic rats by a specific regulation of β3-AR-NOS1-RyR2 signaling pathways.

[Impact of physical activity on metabolic control and the development of chronic complications in patients with type 1 diabetes mellitus]

Together with a balanced diet, regular physical activity is one of the pillars of diabetes mellitus (DM) management. Physical activity theoretically provides the same advantages in people with DM as in the general population and also has some beneficial effects in controlling metabolic factors, such as improving blood glucose levels and insulin sensitivity. In this article, we analyze the main clinical studies published to date that evaluate the impact of physical activity on metabolic control or the development of chronic complications in patients with type 1 diabetes mellitus. In conclusion, most of the evaluated studies show that regular physical activity favorably affects metabolic control in DM (or at least does not have adverse effects). However, there is insufficient information about the impact of physical activity on the development and progression of chronic complications.

Exercise therapy in type 2 diabetes

Structured exercise is considered an important cornerstone to achieve good glycemic control and improve cardiovascular risk profile in Type 2 diabetes. Current clinical guidelines acknowledge the therapeutic strength of exercise intervention. This paper reviews the wide pathophysiological problems associated with Type 2 diabetes and discusses the benefits of exercise therapy on phenotype characteristics, glycemic control and cardiovascular risk profile in Type 2 diabetes patients. Based on the currently available literature, it is concluded that Type 2 diabetes patients should be stimulated to participate in specifically designed exercise intervention programs. More attention should be paid to cardiovascular and musculoskeletal deconditioning as well as motivational factors to improve long-term treatment adherence and clinical efficacy. More clinical research is warranted to establish the efficacy of exercise intervention in a more differentiated approach for Type 2 diabetes subpopulations within different stages of the disease and various levels of co-morbidity.

Clinical measures of physical fitness predict insulin resistance in people at risk for diabetes

BACKGROUND AND PURPOSE

Physical inactivity has been well documented as a risk factor for type 2 diabetes. Previous studies measured the level of physical activity either with questionnaires or with direct measurements of maximum oxygen uptake. However, questionnaires are patient-report measures, and methods for obtaining direct maximum oxygen uptake measurements often are not available clinically. The purpose of this study was to investigate whether clinical measurement of health-related physical fitness with a simple test battery can predict insulin resistance, a precursor of type 2 diabetes, in people at risk for diabetes.

SUBJECTS AND METHODS

A total of 151 volunteers with at least one diabetes risk factor (overweight, hypertension, dyslipidemia, family history, impaired glucose tolerance, gestational diabetes, or delivering a baby weighing more than 4.0 kg) were recruited. Insulin resistance (as determined with the homeostasis model assessment of insulin resistance [HOMA-IR]), physical fitness (including body composition, as determined with the body mass index and waist circumference), muscle strength (handgrip strength [force-generating capacity]), muscle endurance (sit-up test), flexibility (sit-and-reach test), and cardiorespiratory endurance (step test) were measured, and a physical activity questionnaire was administered. Backward regression analysis was used to build the prediction models for insulin resistance from components of physical fitness and physical activity.

RESULTS

Body mass index, muscle strength, and cardiorespiratory fitness predicted HOMA-IR in men (adjusted R(2)=.264). In women, age, waist circumference, and cardiorespiratory fitness were the predictors of HOMA-IR (adjusted R(2)=.438).

DISCUSSION AND CONCLUSION

Clinical measures of physical fitness can predict insulin resistance in people at risk for diabetes. The findings support the validity of clinical measures of physical fitness for predicting insulin resistance in people at risk for diabetes.

Skeletal muscle insulin resistance: roles of fatty acid metabolism and exercise

The purpose of this review is to provide information about the role of exercise in the prevention of skeletal muscle insulin resistance, that is, the inability of insulin to properly cause glucose uptake into skeletal muscle. Insulin resistance is associated with high levels of stored lipids in skeletal muscle cells. Aerobic exercise training decreases the amounts of these lipid products and increases the lipid oxidative capacity of muscle cells. Thus, aerobic exercise training may prevent insulin resistance by correcting a mismatch between fatty acid uptake and fatty acid oxidation in skeletal muscle. Additionally, a single session of aerobic exercise increases glucose uptake by muscle during exercise, increases the ability of insulin to promote glucose uptake, and increases glycogen accumulation after exercise, all of which are important to blood glucose control. There also is some indication that resistance exercise may be effective in preventing insulin resistance. The information provided is intended to help clinicians understand and explain the roles of exercise in reducing insulin resistance.

Epidemiology of diabetes and diabetes-related complications

In 2005, it was estimated that more than 20 million people in the United States had diabetes. Approximately 30% of these people had undiagnosed cases. Increased risk for diabetes is primarily associated with age, ethnicity, family history of diabetes, smoking, obesity, and physical inactivity. Diabetes-related complications--including cardiovascular disease, kidney disease, neuropathy, blindness, and lower-extremity amputation--are a significant cause of increased morbidity and mortality among people with diabetes, and result in a heavy economic burden on the US health care system. With advances in treatment for diabetes and its associated complications, people with diabetes are living longer with their condition. This longer life span will contribute to further increases in the morbidity associated with diabetes, primarily in elderly people and in minority racial or ethnic groups. In 2050, the number of people in the United States with diagnosed diabetes is estimated to grow to 48.3 million.

RESULTS

from randomized controlled trials provide evidence that intensive lifestyle interventions can prevent or delay the onset of diabetes in high-risk individuals. In addition, adequate and sustained control of blood sugar levels, blood pressure, and blood lipid levels can prevent or delay the onset of diabetes-related complications in people with diabetes. Effective interventions, at both the individual and population levels, are desperately needed to slow the diabetes epidemic and reduce diabetes-related complications in the United States. This report describes the current diabetes epidemic and the health and economic impact of diabetes complications on individuals and on the health care system. The report also provides suggestions by which the epidemic can be curbed.

Comparison of combined aerobic and high-force eccentric resistance exercise with aerobic exercise only for people with type 2 diabetes mellitus

BACKGROUND AND PURPOSE

The purpose of this study was to compare the outcomes between a diabetes exercise training program using combined aerobic and high-force eccentric resistance exercise and a program of aerobic exercise only.

SUBJECTS AND METHODS

Fifteen participants with type 2 diabetes mellitus (T2DM) participated in a 16-week supervised exercise training program: 7 (mean age=50.7 years, SD=6.9) in a combined aerobic and eccentric resistance exercise program (AE/RE group) and 8 (mean age=58.5 years, SD=6.2) in a program of aerobic exercise only (AE group). Outcome measures included thigh lean tissue and intramuscular fat (IMF), glycosylated hemoglobin, body mass index (BMI), and 6-minute walk distance.

RESULTS

Both groups experienced decreases in mean glycosylated hemoglobin after training (AE/RE group: -0.59% [95% confidence interval (CI)=-1.5 to 0.28]; AE group: -0.31% [95% CI=-0.60 to -0.03]), with no significant between-group differences. There was an interaction between group and time with respect to change in thigh lean tissue cross-sectional area, with the AE/RE group gaining more lean tissue (AE/RE group: 15.1 cm(2) [95% CI=7.6 to 22.5]; AE group: -5.6 cm(2) [95% CI=-10.4 to 0.76]). Both groups experienced decreases in mean thigh IMF cross-sectional area (AE/RE group: -1.2 cm(2) [95% CI=-2.6 to 0.26]; AE group: -2.2 cm(2) [95% CI=-3.5 to -0.84]) and increases in 6-minute walk distance (AE/RE group: 45.5 m [95% CI=7.5 to 83.6]; AE group: 29.9 m [95% CI=-7.7 to 67.5]) after training, with no between-group differences. There was an interaction between group and time with respect to change in BMI, with the AE/RE group experiencing a greater decrease in BMI.

DISCUSSION AND CONCLUSION

Significant improvements in long-term glycemic control, thigh composition, and physical performance were demonstrated in both groups after participating in a 16-week exercise program.

SUBJECTS

in the AE/RE group demonstrated additional improvements in thigh lean tissue and BMI. Improvements in thigh lean tissue may be important in this population as a means to increase resting metabolic rate, protein reserve, exercise tolerance, and functional mobility.

Diabetes and associated risk factors in patients referred for physical therapy in a national primary care electronic medical record database

OBJECTIVE

The prevalence of diabetes (type 2) in the general population has increased dramatically over the last decade, yet patients with diabetes are rarely referred for physical therapy management of their condition. The majority of patients referred for outpatient physical therapy have musculoskeletal-related conditions. Secondary conditions, such as diabetes, may be prevalent in this population, and physical therapists need to be aware of this to adjust interventions and treatment. The purpose of this article is to describe the prevalence of diabetes and the associated risk factors in adults referred for physical therapy in a primary care outpatient setting.

SUBJECTS AND METHODS

Patients aged 18 years or older referred for physical therapy were identified from the Centricity Electronic Medical Records database during the period of December 13, 1995, to June 30, 2007. Patients were evaluated on the basis of clinical (height, weight, blood pressure, laboratory values), treatment (prescriptions), and diagnostic (ICD-9 codes) criteria to identify the presence of diabetes or associated risk factors (eg, hypertension, elevated triglycerides, low high-density lipoprotein, body mass index, and prediabetes).

RESULTS

There were 52,667 patients referred for physical therapy, the majority of whom were referred for a musculoskeletal-related condition. Approximately 80% of the total study population had diabetes, prediabetes, or risk factors associated with diabetes. The prevalence of diabetes in the study population was 13.2%. Of the diabetes-associated risk factors evaluated, hypertension was the most prevalent (70.4%), and less than half (39.1%) of the study population had an elevated body mass index. Only 20% of the study population had values within normal limits for all clinical, treatment, and diagnostic criteria. Clinical and treatment measurements available to physical therapists identified the majority of associated risk factors.

CONCLUSIONS

Although not the primary indications for referral, diabetes and associated risk factors were identified in a high proportion of the study population. The evaluation of associated conditions in the outpatient orthopedic setting needs to be considered for treatment planning adjustments and to optimize care.

Diabetes mellitus and gait dysfunction: possible explanatory factors

BACKGROUND AND OBJECTIVE

Gait characteristics differ in individuals with diabetes compared with those without diabetes. Limited information regarding potential explanatory factors for this association exists. This study examined the association between diabetes and gait characteristics in older adults and explored potential explanatory factors.

DESIGN

A cross-sectional, observational study design was used.

METHODS

At the 1998-1999 clinic visit, 558 ambulatory older adults (mean age=79 years) from the Pittsburgh site of the Cardiovascular Health Study had an assessment of their gait characteristics, diabetes, health status, cognition, mood, lower-extremity circulation and sensation, vision, lower-extremity strength (force-producing capacity), physical activity, and body mass index (BMI). A series of linear regression models were developed to examine the association between diabetes and gait characteristics and to examine potential explanatory factors for the associations.

RESULTS

Diabetes was related to gait speed (beta=-.06 m/s); however, the association was partially explained by health status variables, cognition, mood, lower-extremity circulation and sensation, visual impairment, lower-extremity strength, physical activity, and BMI. Health status and lower-extremity strength each explained the greatest proportion of the association (beta reduced 66% by each). Diabetes was related to step width (beta=.02 m), and the association could not be explained by the examined factors.

CONCLUSIONS

Diabetes was associated with gait alterations in older adults. Slowed gait speed appears to be secondary to the peripheral effect of the disease on other body systems. The effect of diabetes on step width was not explained in the analyses and may be related to peripheral motor nerve function or central influences of the disease, which could not be assessed in this study.

Diabetes-related microvascular and macrovascular diseases in the physical therapy setting

Physical therapists commonly treat people with diabetes for a wide variety of diabetes-associated impairments, including those from diabetes-related vascular disease. Diabetes is associated with both microvascular and macrovascular diseases affecting several organs, including muscle, skin, heart, brain, and kidneys. A common etiology links the different types of diabetes-associated vascular disease. Common risk factors for vascular disease in people with diabetes, specifically type 2 diabetes, include hyperglycemia, insulin resistance, dyslipidemia, hypertension, tobacco use, and obesity. Mechanisms for vascular disease in diabetes include the pathologic effects of advanced glycation end product accumulation, impaired vasodilatory response attributable to nitric oxide inhibition, smooth muscle cell dysfunction, overproduction of endothelial growth factors, chronic inflammation, hemodynamic dysregulation, impaired fibrinolytic ability, and enhanced platelet aggregation. It is becoming increasingly important for physical therapists to be aware of diabetes-related vascular complications as more patients present with insulin resistance and diabetes. The opportunities for effective physical therapy interventions (such as exercise) are significant.