Is there a different rating of perceived exertion in men with type 2 diabetes mellitus?

Objective: Studies show that patients with type 2 diabetes mellitus (T2DM) do not engage in regular exercise as often as individuals without T2DM. In addition to numerous barriers to engaging in regular exercise, a different rating of perceived exertion (RPE) during physical activity has been hypothesized to play a role. Therefore, this study investigates whether T2DM affects RPE. Methods: RPE values (BORG scale ratings) and heart rate (HR) data were analyzed during an endurance step test (25 W + 25 W every 2 min) at different workloads relative to the individual maximum load (50%, 70% and 90% of peak workload (Wpeak)) in patients with T2DM and in non-diabetic control (CON) subjects (n = 12 in each group). Furthermore, in a larger group of overweight patients with T2DM (n = 81), it was investigated whether glycated hemoglobin (HbA1c) levels correlate with RPE values at the different relative loads. Results: Neither RPE nor HR values significantly differed between T2DM and CON subjects at 50%, 70% or 90% of Wpeak. No significant correlations were identified between HbA1c levels and RPE values. Conclusion: There is no evidence in our study that T2DM leads to a different perception of physical exertion. Other causes must therefore be responsible for the increased lack of motivation of T2DM patients to engage in regular exercise.

From Zero to Hero: Type 2 Diabetes Mellitus Patients Hike on the Way of St. James-A Feasibility Study with Analyses of Patients' Quality of Life, Diabetes Distress and Glucose Profile.

This study investigates the feasibility of an accompanied 5-day hiking tour (Way of St. James) for type 2 diabetes mellitus (T2DM) patients and its impact on their quality of life/well-being, diabetes distress and glucose profile. Twenty-three T2DM patients (with and without insulin therapy) participated in the study. The 120 km pilgrimage (from Ferrol to Santiago de Compostela, Spain) was accompanied by three physicians, two diabetes counselors and one sports scientist. Quality of life/well-being was assessed by the World Health Organization's (WHO)-5 questionnaire, and diabetes distress was evaluated based on the Problem Areas in Diabetes (PAID) scale. The glucose levels of six insulin-treated patients were measured using continuous glucose monitoring (CGM) devices, considering that insulin-treated patients can be at increased risk of exercise-induced hypoglycemia. A significant improvement in quality of life/well-being was reported (p < 0.001), while diabetes distress did not change significantly (p = 0.203). Only two of the six insulin-treated patients showed moderate hypoglycemic episodes between 0.97% and 5.21% time below range per day, with glucose levels between 53−70 mg/dL. Hiking tours such as the one organized for this study can improve quality of life/well-being without increasing diabetes distress and are considered relatively safe for T2DM patients, even for those being treated with insulin.

Effects of a Combined Endurance/Strength Training Program on Circulating Irisin Levels in Overweight/Obese Men and Women with Type 2 Diabetes Mellitus.

Irisin is a promising therapeutic target in patients with type 2 diabetes mellitus (T2DM), as studies have demonstrated that irisin can induce "browning" of adipocytes and mitigate pro-inflammatory conditions. Sex-specific changes in irisin levels have been reported in a study involving healthy men and women following physical training. The present study aims to analyze the effects of an 8-week training intervention on circulating irisin levels in patients with T2DM and to find out whether the training responses differ between T2DM men and women. Twenty-nine overweight/obese T2DM patients (19 men, 10 women; age: 46-74 years; body mass index >25 kg/m2) participated in a combined moderate-intensity endurance/strength training program (3 times a week). The irisin levels of men and women did not differ significantly. The post-training irisin levels did not differ significantly from the pre-training values, and there was no interaction effect of sex. This study shows no training-induced (sex-specific) changes in circulating irisin levels in T2DM patients. Large-scale studies using other forms of training are needed to fully clarify whether basal irisin levels can be changed in T2DM men and/or women to counteract T2DM.

Exercise training in the treatment of paroxysmal atrial fibrillation: study protocol of the Cologne ExAfib Trial.

INTRODUCTION: Atrial fibrillation (AF) is the most common form of cardiac arrhythmia and is associated with a number of comorbidities such as coronary artery disease and heart failure. While physical activity is already implemented in current international guidelines for the prevention and treatment of AF, the precise role of different types of exercise in the management of AF remains to be elucidated. The primary aim of the Cologne ExAfib Trial is to assess the feasibility and safety of different exercise modes in patients diagnosed with paroxysmal AF. Secondary outcomes include assessments of physical function, AF burden, quality of life and inflammation, as well as morphological and cardiac adaptations. METHODS AND ANALYSIS: The study opened for recruitment in September 2019. In the initial pilot phase of this four-armed randomised controlled trial, we aim to enrol 60 patients between 60 years and 80 years of age with paroxysmal AF. After screening and pretesting, patients are randomised into one of the following groups: high-intensity interval training (4×4 min at 75%-85% peak power output (PPO)), moderate-intensity continuous training (25 min at 55%-65% PPO), strength training (whole body, 3 sets of 6-12 repetitions at 70%-90% one repetition maximum [1RM]) or a usual-care control group. Training is performed two times per week for 12 weeks. If the feasibility and safety can be confirmed through the initial pilot phase, the recruitment will be continued and powered for a clinical endpoint.Feasibility and safety are assessed by measures of recruitment and completion, programme tolerance and adherence as well as reported adverse events, including hospitalisation rates. Secondary endpoints are assessed by measures of peak oxygen consumption and the 1RM of selected muscle groups, questionnaires concerning quality of life and AF burden, serum blood samples for the analysis of C reactive protein, interleukin-6, tumour necrosis factor alpha and N-terminal pro-brain natriuretic peptide concentrations and ultrasound for muscle and heart morphology as well as cardiac function. ETHICS AND DISSEMINATION: Ethics approval was obtained from the ethics committee of the German Sport University Cologne (No.: 175/2018). All procedures performed in studies involving human participants are in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. Manuscripts will be written based on international authorship guidelines. No professional writers will be commissioned for manuscript drafting. The findings of this study will be published in peer-reviewed journals and presented at leading exercise and medicine conferences TRIAL REGISTRATION NUMBER: The study is registered both at the German and at the WHO trial registers (DRKS00016637); Pre-results.

Effects of exercising before breakfast on the health of T2DM patients-A randomized controlled trial.

This is the first study to examine whether training before breakfast in the overnight-fasted state is more effective in improving the health of patients with type 2 diabetes mellitus (T2DM) than after breakfast in the fed state. Thirty T2DM patients (60 ± 8 years, 33.7 ± 4.6 kg/m2 ) were randomly assigned to the F group (training in the overnight-fasted state (n = 15)) and to the C group (training in the fed state (control group, n = 15)). All patients completed an 8-week combined endurance/strength training program. Physical training significantly increased time to physical exhaustion during an endurance test (+10.4%), power output during strength tests (chest presses: +36.7% and seated rows: +37.8%), and fat-free mass (+1.7 kg). Body fat mass (-1.9 kg), glycated hemoglobin (HbA1c) values (absolute change: -0.3%), serum insulin values (-2.5 microU/mL), the homeostatic model assessment for insulin resistance (HOMA-IR) index (-1.1), and circulating triglyceride levels (-31 mg/dL) decreased significantly from pre- to post-training. The training had no effect on body mass index, serum fasting glucose, total cholesterol, low-density lipoprotein/high-density lipoprotein ratio or interleukin (IL)-6, IL-10 and tumor necrosis factor (TNF)α levels. Analyses of variance revealed no time × group interaction for any variable (P > .05). The training was effective in improving the health of T2DM patients. However, the preliminary study's data do not provide any evidence that the nutritional state (overnight-fasted or fed) in regular physical training plays a significant role for training-induced adaptations in T2DM patients. Full trials (using other training protocols as well) should be conducted to gain further knowledge about the relevance of pre-exercise breakfast ingestion.

Strength training alters MCT1-protein expression and exercise-induced translocation in erythrocytes of men with non-insulin-dependent type-2 diabetes.

We investigated the cellular distribution of lactate transporter (MCT1) and its chaperone CD147 (using immunohistochemistry and fluorescence-activated cell sorting) in the erythrocytes of men with non-insulin-dependent type-2 diabetes (NIDDM, n = 11, 61 ± 8 years of age) under acute exercise (ergometer cycling test, World Health Organisation scheme) performed before and after a 3-month strength training program. Cytosolic MCT1 distribution and membraneous CD147 density did not change after acute exercise (ergometer). After the 3-month strength training, MCT1-density was increased and the reaction of MCT1 (but not that of CD147) towards acute exercise (ergometer) was altered. MCT1 localisation was shifted from the centre to the cellular membrane. This resulted in a decrease in the immunohistochemically measured cytosolic MCT1-density. We conclude that strength training alters the acute exercise reaction of MCT1 but not that of CD147 in erythrocytes in patients with NIDDM. This reaction may contribute to long-term normalisation and stabilisation of the regulation of lactate plasma concentration in NIDDM.

Training-induced alterations of skeletal muscle mitochondrial biogenesis proteins in non-insulin-dependent type 2 diabetic men.

This study investigates whether regular physical activity (moderate endurance or resistance training twice a week for 3 months) influences the key regulatory molecules of mitochondrial biogenesis (peroxisome proliferator-activated receptor gamma coactivator-1α (PGC1α), nuclear respiratory factor-1 (NRF1), and mitochondrial transcription factor A (TFAM)) in patients suffering from non-insulin-dependent type 2 diabetes mellitus (T2DM) (n = 16, years = 62 ± 7, body mass index (BMI) = 30 ± 4 kg/m(2)). Seven T2DM men took part in endurance training, and 9 men participated in resistance training. BMI-matched non-diabetic male control subjects (CON) (n = 7, years = 53 ± 6, BMI = 30 ± 4 kg/m(2)) were studied for comparison. The protein contents of PGC1α, NRF1, and TFAM were determined using immunohistochemical staining methods on biopsies taken from the musculus vastus lateralis. At baseline, no differences were observed in NRF1-density between the T2DM men and the CON, while the contents of PGC1α and TFAM were decreased in the T2DM men. PGC1α and TFAM contents were not changed in the T2DM patients after the training period, but NRF1 was decreased. The down-regulation of mitochondrial signaling molecules might explain the patho-physiological reduction in mitochondrial biogenesis found in T2DM. Physical training, as performed in our study, did not reverse the down-regulation of mitochondrial signaling molecules--at least not after 3 months. [corrected].

Training increases peroxiredoxin 2 contents in the erythrocytes of overweight/obese men suffering from type 2 diabetes.

Type 2 diabetes mellitus (T2DM) is associated with an increased release of free radicals which play an important role in the manifestation of diabetes and in the progression of diabetic complications. Peroxiredoxins are thought to be essential components of the erythrocyte antioxidative defense. Therefore, we compared peroxiredoxin isoform contents (PRDX1-6 immuno-histochemial stainings) in the erythrocytes of overweight/obese T2DM men (n = 6) and of BMI-matched non-diabetic male control subjects (n = 6). Only erythrocyte PRDX1 and PRDX2 proteins were detectable using immunohistochemical methods. PRDX1 was significantly increased in T2DM men relative to control subjects (+95.9%, P ≤ 0.05). Furthermore, we studied the influence of a 3-month endurance training program (3 times a week, cycling at 75% maximal heart rate) on erythrocyte PRDX1 and PRDX2 contents in overweight/obese T2DM men (n = 11). Training significantly increased PRDX2 at rest (+96%, P ≤ 0.05). The up-regulation of the peroxiredoxin system may help counteract free radicals in the erythrocytes of T2DM patients.

The influence of resistance training on patients with metabolic syndrome--significance of changes in muscle fiber size and muscle fiber distribution.

People who are afflicted with "metabolic syndrome" exhibit multiple coronary disease risk factors such as insulin resistance, hypertension, hyperlipidemia, or obesity. Twenty-six volunteers (13 women and 13 men) with such disease risk factors (56 ± 5 years) participated in a 14-week resistance training program. Given the fact that resistance training may improve cardiometabolic parameters, the fasting total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides, insulin, glucose value, homeostatic model assessment (HOMA) index, and blood pressure and body mass index (BMI) were measured before and after the training intervention. In addition, muscle biopsies from the vastus lateralis muscle of 11 of the men and 5 of the women were analyzed to determine whether changes in the muscle morphology influence the cardiometabolic parameters. Resistance training resulted in a significant increase in fasting HDL for the entire group (from 44.35 ± 9.43 to 48.57 ± 10.96 mg·dl(-1), p = 0.016). No other blood parameter changed significantly. No change was observed in the HOMA index, blood pressure, or BMI. The muscle fiber type distribution did not change, but a significant hypertrophy of muscle fibers was evident (an increase of the ellipse minor axis of 67.3 ± 16.6 to 72.1 ± 12.3 µm, p = 0.004). Moderate intensity resistance training, as was performed in our study, induces hypertrophic impulses but does not seem to have a clear positive influence on cardiometabolic risk factors. However, 2 sessions of moderate intensity resistance training per week can enhance the fasting HDL cholesterol in middle-aged subjects.