Effects of Nordic walking on cardiovascular risk factors in overweight individuals with type 2 diabetes, impaired or normal glucose tolerance

High-Intensity Interval Versus Moderate-Intensity Continuous Exercise Training on Glycemic Control, Beta Cell Function, and Aerobic Fitness in Women with Type 2 Diabetes

Objective: This study aimed to compare the effects of High-Intensity Interval Training (HIIT) and Moderate-Intensity Continuous Training (MICT) on glycemic control, beta-cell function, and aerobic fitness in women with Type 2 Diabetes Mellitus (T2DM). Methods: Thirty-six women with T2DM were assigned equally to HIIT, MICT, and control (CON) groups. Participants in the exercise cohorts underwent a 12-week training regimen (three sessions per week), while the CON group maintained an inactive lifestyle. Glycaemia variables, beta-cell function, maximal oxygen uptake (VO2max), lipid profiles, and body composition were assessed at baseline and post-intervention. Results: Both HIIT and MICT interventions led to significant improvements in glucose, insulin, HbA1c, and insulin resistance index. Moreover, visceral adiposity index (VAI), lipid accumulation product (LAP), total cholesterol (TC), and low-density lipoprotein (LDL) levels significantly decreased in the HIIT and MICT groups after 12 weeks. Triglyceride (TG) levels decreased only after MICT, while high-density lipoprotein (HDL) levels increased after both interventions. Maximal oxygen uptake (VO2max), body mass, body mass index (BMI), and waist circumference (WC) significantly improved in all exercise groups. Notably, the HIIT group showed greater reductions in body mass compared to MICT. Nevertheless, beta-cell function remained unaltered after these two exercise regimens. Conclusion: Both HIIT and MICT interventions effectively managed T2DM in women, regardless of exercise intensity. The HIIT regimen can be considered for time-efficient lifestyle interventions in people with T2DM.

Exercise training modalities in prediabetes: a systematic review and network meta-analysis

Background

Lifestyle modification based on exercise intervention is still the primary way to delay or reverse the development of diabetes in patients with prediabetes. However, there are still challenges in setting up a detailed exercise prescription for people with prediabetes. This study mainly ranks exercise prescriptions by comparing the improvement of glucose and lipid metabolism and the level of weight loss in patients.

Method

All studies on exercise intervention in prediabetes were identified by searching five electronic databases. Risk assessment and meta-analysis were performed on eligible studies.

Results

Twenty-four studies involving 1946 patients with prediabetes and seven exercise intervention models were included in the final analysis. The meta-analysis showed that exercise of any type was more effective for glycemic control in prediabetes than no exercise. However, the changes in blood glucose were moderate. In prediabetes, combining moderate-intensity aerobic exercise with low-to moderate-load resistance training showed the most significant improvements in glycosylated hemoglobin (HbA1c), body mass index (BMI), body weight (BW), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL) (P-score=0.82; 0.70; 0.87; 1; 0.99), low-to moderate-load resistance training showed the most significant improvements in fasting blood glucose (FBG) (P-score=0.98), the vigorous-intensity aerobic exercise showed the most significant improvements in 2-hour post-meal blood glucose (2hPG) and systolic blood pressure (SBP) (P-score=0.79; 0.78), and moderate-intensity aerobic exercise showed the most significant improvements in diastolic blood pressure (DBP) (P-score=0.78).

Conclusion

In summary, moderate-intensity aerobic exercise, low-to moderate-load resistance training and the combination of both have beneficial effects on glycemic control, weight loss, and cardiovascular health in patients with prediabetes. These findings provide valuable guidance for rehabilitation clinicians and patients alike to follow.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD 42021284922.

Effect of physical activity and different exercise modalities on glycemic control in people with prediabetes: a systematic review and meta-analysis of randomized controlled trials

Background

Numerous studies have shown the beneficial effects of exercise on glycemic control in people with prediabetes. However, the most effective exercise modality for improving glycemic control remains unclear. We aimed to assess which exercise training modality is most effective in improving glycemic control in a population with prediabetes.

Methods

We conducted searches in Pubmed/MEDLINE, EMBASE, SPORTDiscus, Web of Science, PEDro, BVS, and the Cochrane Library from inception to June 2022. Included studies reported fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), and 2-hour postprandial (2hPP) levels and implemented an exercise program lasting at least 12 weeks in adults with prediabetes. We performed a direct meta-analysis using a random-effects model and a network meta-analysis. Cochran's Q statistic and the inconsistency I2 test were used to assess the heterogenicity between studies.

Results

Twenty trials were included, with 15 trials (comprising 775 participants with prediabetes) combined in the meta-analysis, and 13 in the network meta-analysis. The meta-analysis results did not show a statistically significant reduction in fasting plasma glucose (FPG) after aerobic training (AT) intervention compared to a control group (mean (95%CI) difference = -5.18 (-13.48; 3.12) mg/dL, Z=1.22, p=0.22). However, a difference of -7.25 (-13.79; -0.71) mg/dL, p=0.03, in FPG after interval training (IT) intervention was detected compared to a control group. After resistance training (RT) intervention, FPG was significantly lower -6.71 (-12.65,-0.77) mg/dL, Z=2.21, p=0.03, and HbA1c by -0.13 (-0.55, 0.29), p=0.54, compared to the control group. The impact of RT compared to no intervention on 2hPP was not statistically significant (p=0.26). The network meta-analysis did not show statistical significance. Most of the studies presented an unclear risk of bias, and a low and very low-quality of evidence. According to the GRADE criteria, the strength of the body of evidence was low.

Conclusion

Resistance training and IT had demonstrated benefits on glycemic indices, especially on FPG, in a population with prediabetes. Further studies with larger sample sizes and a more robust methodology that compare different types of exercise modalities, frequencies, and durations, are needed to establish a beneficial exercise intervention.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=370688, identifier CRD42022370688.

Nordic Walking Improves Cardiometabolic Parameters, Fitness Performance, and Quality of Life in Older Adults With Type 2 Diabetes

OBJECTIVE

To assess the effect of Nordic walking (NW) on cardiometabolic health, physical performance, and well-being in sedentary older adults with type 2 diabetes (T2D).

METHODS

Fifteen subjects with T2D (female, 5; male, 10; age, 65 ± 6.2 years [mean ± standard deviation]; body mass index, 27.3 ± 4.9 kg/m² [mean ± standard deviation]) were enrolled in a 6-month NW training program. The fasting glucose and glycosylated hemoglobin levels, lipid profile (total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides), systolic blood pressure (SBP), and diastolic blood pressures were measured before and after the intervention. Participants' quality of life (Short-Form Health Survey) and physical fitness (6-minute walking test) were also evaluated.

RESULTS

Compared with baseline, NW significantly improved the fasting glucose level (103.5 ± 18.5 vs 168.7 ± 37.7 mg/dL, P = .01), SBP (121.8 ± 12.2 vs 133 ± 14.4 mm Hg, P = .02), physical fitness (759.88 ± 69 vs 615.5 ± 62.6 m, P < .001), and both mental health (54.5 ± 4.4 vs 45.7 ± 5.6, P < .01) and physical health (49.8 ± 4.7 vs 40.3 ± 5.9, P < .01). The levels of glycosylated hemoglobin (6.15% ± 0.8% vs 6.4% ± 1%, P = .46), total cholesterol (162.2 ± 31.2 vs 175.5 ± 28.8 mg/dL, P = .13), low-density lipoprotein cholesterol (95.2 ± 24.2 vs 106.3 ± 32.3 mg/dL, P = .43), and triglycerides (135.5 ± 60.8 vs 127.6 ± 57.4 mg/dL, P = 0.26) improved without reaching significance.

CONCLUSION

NW training improved the glycemic levels, SBP, physical fitness, and perception of quality of life in older adults with T2D. NW represents a suitable complementary strategy to improve the global health status in this population.

A systematic review of adherence to physical activity interventions in individuals with type 2 diabetes

Lifestyle interventions are pivotal for successful management of type 2 diabetes (T2D), however, the proportion of people with T2D adhering to physical activity advice has not been thoroughly studied. The purpose of this systematic review was to summarise the evidence on adherence to exercise or physical activity components in lifestyle interventions in those with T2D. We searched MEDLINE EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews and Scopus on 12 November 2019. Eligible studies enrolled adults with T2D and reported the proportion of adherence to lifestyle interventions as a primary or secondary outcome. We included 11 studies (nine randomised controlled trials (RCTs) enrolling 1717 patients and two nonrandomised studies enrolling 62 patients). Only one of the studies had low risk of bias. The proportion of participants adhering to physical activity varied from 32% to 100% with a median of 58%. Adherence was higher in interventions using supervised training and lowest in interventions using remote coaching and the adherence rate in observational studies was higher compared to RCTs (92% vs. 55%; p < 0.01). Study duration, risk of bias, or participants' sex, were not associated with adherence to physical activity. The proportion of those with T2D adhering to physical activity interventions for T2D varies widely and most of the included studies had a high risk of bias. These findings have important implications for planning and power analysis of future trials and when counselling patients about lifestyle interventions including physical activity or exercise components.

Comparisons of different exercise interventions on glycemic control and insulin resistance in prediabetes: a network meta-analysis

BACKGROUND

In order to recommend the optimal type of exercise for type 2 diabetes prevention, different exercise interventions were compared with respect to their effects on glycemic control and insulin resistance.

METHODS

Studies on the curative effect of aerobic exercise training (AET), resistance training (RT), or control training (CT) on prediabetes were retrieved from the PubMed, Embase, SPORTDiscus, and Cochrane Library databases. Body mass index (BMI); homeostasis model assessment of insulin resistance index (HOMA-IR); and fasting blood glucose (FBG), glycated hemoglobin (HbA1c), and insulin levels were used as outcome indicators. The Q statistic was calculated to evaluate heterogeneity within studies. A fixed- or random-effects model was used for pooling data based on nonsignificant or significant heterogeneities. A consistency test was conducted using a node-splitting analysis.

RESULTS

A total of 13 eligible studies were included. The results of the direct meta-analysis indicated that AET or RT could significantly reduce the HbA1c level in prediabetic individuals compared to CT [AET vs. CT: standardized mean difference (SMD) = - 0.6739, 95% confidence interval (CI) = - 0.9424 to - 0.4055 to RT vs. CT: SMD = - 1.0014, 95% CI = - 1.3582 to - 0.6446]. The findings from the network meta-analysis showed that there were no statistical differences among the four comparisons for all the indicators except for lower HbA1c level (SMD = - 0.75, 95% CI = - 1.31 to - 0.19) and HOMA-IR (SMD = - 1.03, 95% CI = - 1.96 to - 0.10) in the AET group than in the CT group. In addition, prediabetic individuals in the AET + RT group showed greater control of BMI and insulin and FBG levels than those in the other groups, whereas AET was the most effective in controlling HbA1c and HOMA-IR levels in prediabetic individuals.

CONCLUSION

AET, AET + RT, and RT exerted beneficial effects on insulin resistance and glycemic control in prediabetic patients. From the existing data, AET or AET + RT is preferentially recommended for these patients, although further studies may unveil RT as a promising therapy. Benefits from all types of exercise seem to occur in an intensity-dependent manner.

Effect of exercise on cardiometabolic health of adults with overweight or obesity: Focus on blood pressure, insulin resistance, and intrahepatic fat-A systematic review and meta-analysis

This systematic review examined the impact of exercise intervention programs on selected cardiometabolic health indicators in adults with overweight or obesity. Three electronic databases were explored for randomized controlled trials (RCTs) that included adults with overweight or obesity and provided exercise-training interventions. Effects on blood pressure, insulin resistance (homeostasis model of insulin resistance, HOMA-IR), and magnetic resonance measures of intrahepatic fat in exercise versus control groups were analyzed using random effects meta-analyses. Fifty-four articles matched inclusion criteria. Exercise training reduced systolic and diastolic blood pressure (mean difference, MD = -2.95 mmHg [95% CI -4.22, -1.68], p < 0.00001, I²  = 63% and MD = -1.93 mmHg [95% CI -2.73, -1.13], p < 0.00001, I²  = 54%, 60 and 58 study arms, respectively). Systolic and diastolic blood pressure decreased also when considering only subjects with hypertension. Exercise training significantly decreased HOMA-IR (standardized mean difference, SMD = -0.34 [-0.49, -0.18], p < 0.0001, I²  = 48%, 37 study arms), with higher effect size in subgroup of patients with type 2 diabetes (SMD = -0.50 [95% CI: -0.83, -0.17], p = 0.003, I²  = 39%). Intrahepatic fat decreased significantly after exercise interventions (SMD = -0.59 [95% CI: -0.78, -0.41], p < 0.00001, I²  = 0%), with a larger effect size after high-intensity interval training. In conclusion, exercise training is effective in improving cardiometabolic health in adults with overweight or obesity also when living with comorbitidies.

Walking for subjects with type 2 diabetes: a systematic review and joint AMD/SID/SISMES evidence-based practical guideline

Aims

Regular exercise is considered a cornerstone in the management of type 2 diabetes mellitus (T2DM). It improves glucose control and cardiovascular risk factors, contributes to weight loss, and also improves general well-being, likely playing a role in the prevention of chronic complications of diabetes. However, compliance to exercise recommendations is generally inadequate in subjects with T2DM. Walking is the most ancestral form of physical activity in humans, easily applicable in daily life. It may represent, in many patients, a first simple step towards lifestyle changes. Nevertheless, while most diabetic patients do not engage in any weekly walking, exercise guidelines do not generally detail how to improve its use. The aims of this document are to conduct a systematic review of available literature on walking as a therapeutic tool for people with T2DM, and to provide practical, evidence-based clinical recommendations regarding its utilization in these subjects.

Data synthesis

Analysis of available RCTs proved that regular walking training, especially when supervised, improves glucose control in subjects with T2DM, with favorable effects also on cardiorespiratory fitness, body weight, and blood pressure. Moreover, some recent studies have shown that even short bouts of walking, used for breaking prolonged sitting, can ameliorate glucose profiles in diabetic patients with sedentary behavior.

Conclusions

There is sufficient evidence to recognize that walking is a useful therapeutic tool for people with T2DM. This document discusses theoretical and practical issues for improving its use.

Walking for hypertension

BACKGROUND

Increased physical activity has been recommended as an important lifestyle modification for the prevention and control of hypertension. Walking is a low-cost form of physical activity and one which most people can do. Studies testing the effect of walking on blood pressure have revealed inconsistent findings.

OBJECTIVES

To determine the effect of walking as a physical activity intervention on blood pressure and heart rate.

SEARCH METHODS

We searched the following databases up to March 2020: the Cochrane Hypertension Specialised Register, CENTRAL (2020, Issue 2), Ovid MEDLINE, Ovid Embase, CINAHL, PsycINFO, SPORTDiscus, PEDro, the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also searched the following Chinese databases up to May 2020: Index to Taiwan Periodical Literature System; National Digital Library of Theses and Dissertation in Taiwan; China National Knowledge Infrastructure (CNKI) Journals, Theses & Dissertations; and Wanfang Medical Online. We contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions.

SELECTION CRITERIA

Randomised controlled trials of participants, aged 16 years and over, which evaluated the effects of a walking intervention compared to non-intervention control on blood pressure and heart rate were included.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Where data were not available in the published reports, we contacted authors. Pooled results for blood pressure and heart rate were presented as mean differences (MDs) between groups with 95% confidence intervals (CIs). We undertook subgroup analyses for age and sex. We undertook sensitivity analyses to assess the effect of sample size on our findings.

MAIN RESULTS

A total of 73 trials met our inclusion criteria. These 73 trials included 5763 participants and were undertaken in 22 countries. Participants were aged from 16 to 84 years and there were approximately 1.5 times as many females as males. The characteristics of walking interventions in the included studies were as follows: the majority of walking interventions was at home/community (n = 50) but supervised (n = 36 out of 47 reported the information of supervision); the average intervention length was 15 weeks, average walking time per week was 153 minutes and the majority of walking intensity was moderate. Many studies were at risk of selection bias and performance bias. Primary outcome We found moderate-certainty evidence suggesting that walking reduces systolic blood pressure (SBP) (MD -4.11 mmHg, 95% CI -5.22 to -3.01; 73 studies, n = 5060). We found moderate-certainty evidence suggesting that walking reduces SBP in participants aged 40 years and under (MD -4.41 mmHg, 95% CI -6.17 to -2.65; 14 studies, n = 491), and low-certainty evidence that walking reduces SBP in participants aged 41 to 60 years (MD -3.79 mmHg, 95% CI -5.64 to -1.94, P < 0.001; 35 studies, n = 1959), and those aged 60 years of over (MD -4.30 mmHg, 95% CI -6.17 to -2.44, 24 studies, n = 2610). We also found low certainty-evidence suggesting that walking reduces SBP in both females (MD -5.65 mmHg, 95% CI -7.89 to -3.41; 22 studies, n = 1149) and males (MD -4.64 mmHg, 95% CI -8.69 to -0.59; 6 studies, n = 203). Secondary outcomes We found low-certainty evidence suggesting that walking reduces diastolic blood pressure (DBP) (MD -1.79 mmHg, 95% CI -2.51 to -1.07; 69 studies, n = 4711) and heart rate (MD -2.76 beats per minute (bpm), 95% CI -4.57 to -0.95; 26 studies, n = 1747). We found moderate-certainty evidence suggesting that walking reduces DBP for participants aged 40 years and under (MD -3.01 mmHg, 95% CI -4.44 to -1.58; 14 studies, n = 491) and low-certainty evidence suggesting that walking reduces DBP for participants aged 41 to 60 years (MD -1.74 mmHg, 95% CI -2.95 to -0.52; 32 studies, n = 1730) and those aged 60 years and over (MD -1.33 mmHg, 95% CI -2.40 to -0.26; 23 studies, n = 2490). We found moderate-certainty evidence that suggests walking reduces DBP for males (MD -2.54 mmHg, 95% CI -4.84 to -0.24; 6 studies, n = 203) and low-certainty evidence that walking reduces DBP for females (MD -2.69 mmHg, 95% CI -4.16 to -1.23; 20 studies, n = 1000). Only 21 included studies reported adverse events. Of these 21 studies, 16 reported no adverse events, the remaining five studies reported eight adverse events, with knee injury being reported five times.

AUTHORS' CONCLUSIONS

Moderate-certainty evidence suggests that walking probably reduces SBP. Moderate- or low-certainty evidence suggests that walking may reduce SBP for all ages and both sexes. Low-certainty evidence suggests that walking may reduce DBP and heart rate. Moderate- and low-certainty evidence suggests walking may reduce DBP and heart rate for all ages and both sexes.

Walking for subjects with type 2 diabetes: A systematic review and joint AMD/SID/SISMES evidence-based practical guideline

AIMS

Regular exercise is considered a cornerstone in the management of type 2 diabetes mellitus (T2DM). It improves glucose control and cardiovascular risk factors, contributes to weight loss, and also improves general well-being, likely playing a role in the prevention of chronic complications of diabetes. However, compliance to exercise recommendations is generally inadequate in subjects with T2DM. Walking is the most ancestral form of physical activity in humans, easily applicable in daily life. It may represent, in many patients, a first simple step towards lifestyle changes. Nevertheless, while most diabetic patients do not engage in any weekly walking, exercise guidelines do not generally detail how to improve its use. The aims of this document are to conduct a systematic review of available literature on walking as a therapeutic tool for people with T2DM, and to provide practical, evidence-based clinical recommendations regarding its utilization in these subjects.

DATA SYNTHESIS

Analysis of available RCTs proved that regular walking training, especially when supervised, improves glucose control in subjects with T2DM, with favorable effects also on cardiorespiratory fitness, body weight and blood pressure. Moreover, some recent studies have shown that even short bouts of walking, used for breaking prolonged sitting, can ameliorate glucose profiles in diabetic patients with sedentary behavior.

CONCLUSIONS

There is sufficient evidence to recognize that walking is a useful therapeutic tool for people with T2DM. This document discusses theoretical and practical issues for improving its use. This article is co-published in the journals Sport Sciences for Health and Nutrition, Metabolism and Cardiovascular Diseases.

Effects of a Supervised Nordic Walking Program on Obese Adults with and without Type 2 Diabetes: The C.U.R.I.A.Mo. Centre Experience

Exercise is a convenient non-medical intervention, commonly recommended in metabolic syndrome and type 2 diabetes (DM2) managements. Aerobic exercise and aerobic circuit training have been shown to be able to reduce the risk of developing DM2-related complications. Growing literature proves the usefulness of Nordic walking as exercise therapy in different disease populations, therefore it has a conceivable use in DM2 management. Aims of this study were to analyze and report the effects of two different supervised exercises (gym-based exercise and Nordic walking) on anthropometric profile, blood pressure values, blood chemistry and fitness variables in obese individuals with and without DM2. In this study, 108 obese adults (aged 45-65 years), with or without DM2, were recruited and allocated into one of four subgroups: (1) Gym-based exercise program (n = 49) or (2) Nordic walking program (n = 37) for obese adults; (3) Gym-based exercise program (n = 10) or (4) Nordic walking program (n = 12) for obese adults with DM2. In all exercise subgroups, statistically significant improvements in body weight, body mass index, fat mass index, muscular flexibility and maximal oxygen uptake (VO2 max) were observed. Moreover, a higher percentage of adherence to the gym-based program compared to Nordic walking was recorded. Our findings showed that, notwithstanding the lower adherence, a supervised Nordic walk is effective as a conventional gym-based program to improve body weight control, body composition parameters, muscular flexibility and VO2 max levels in obese adults with and without type 2 diabetes.

Nordic Walking for Overweight and Obese People: A Systematic Review and Meta-Analysis

BACKGROUND

Nordic walking (NW) is a potentially beneficial exercise strategy for overweight and obese people. To date, no reviews have synthesized the existing scientific evidence regarding the effects of NW on this population. This systematic review and meta-analysis aimed to identify the characteristics, methodological quality, and results of the investigations that have studied the effects of NW in overweight and obese individuals.

METHODS

Six electronic databases were searched up to June 2019 for studies that examined the effects of NW on people with a body mass index ≥ 25 kg/m2. The methodological quality of the included randomized controlled trials was retrieved from the physiotherapy evidence database or evaluated using the physiotherapy evidence database scale.

RESULTS

Twelve studies were included in the review. The investigations were mostly good-to-fair methodological quality. NW groups had a significant improvement on parameters such as fasting plasma glucose, abdominal adiposity, and body fat compared with the baseline, but no significant improvements were found when compared with control groups.

CONCLUSIONS

NW can potentially lead to improvements in parameters related to major health outcomes in overweight and obese people. The lack of control for confounding variables in the analyzed studies prevents further elaboration on its potential benefits.

Nordic Walking Promoted Weight Loss in Overweight and Obese People: A Systematic Review for Future Exercise Prescription

The aim of this systematic review was to analyze the effect of Nordic Walking (NW) on anthropometric parameters, body composition, cardiovascular parameters, aerobic capacity, blood sample, and glucose tolerance in overweight and obese subjects. The main keywords "Nordic Walking" or "Pole Walking", associated with either "obese", "obesity", "overweight", or "weight loss" were used on the online database MEDLINE, PubMed, SPORTDiscus and Scopus. Additionally, references of the studies included were screened to identify eligible articles. Applying the inclusion and exclusion criteria, ten manuscripts were considered as eligible for this review. The results of the studies were categorized in several domains with regard to "anthropometric parameters and body composition", "cardiovascular parameters and aerobic capacity", and "blood sample and glucose tolerance". The results showed positive effects on the anthropometric parameters, body composition, cardiovascular parameters, blood sample, and glucose tolerance. The greatest improvements were observed in supervised and high weekly frequency of NW interventions. NW could be considered as an effective modality through which to involve the obese in physical activity. For weight loss, NW should be prescribed 4-5 times per week, at least 60 min per session, preferably combined with diet control.

Changes in Vitamin D Status in Overweight Middle-Aged Adults with or without Impaired Glucose Metabolism in Two Consecutive Nordic Summers

Background

Sun exposure is the main driver of vitamin D synthesis. High latitude, obesity, and type 2 diabetes mellitus (T2DM) are all risk factors for vitamin D deficiency. However, the seasonal variation in vitamin D concentrations (25[OH]D) in such populations before and after sun exposure during the summer is unknown. Therefore, we investigated 25[OH]D status before and after two consecutive summers in high latitude and its associations with body fat, sex, and glucose metabolism.

Methods

158 participants from Sweden (87 women, 71 men; mean age, 60 ± 5 y; body mass index ≥ 25 kg/m²) and 25[OH]D were measured and evaluated in relation to normal or impaired glucose tolerance, body composition, and dietary habits during summer season.

Results

Eighty-four percent of the participants were categorized with low to deficient 25[OH]D values before summer (55.1 ± 21.7 nmol·L⁻¹), with a significant increase after the summer season (66.3 ± 21.0 nmol·L⁻¹; P < 0.001). However, the values remained below the recommended range (76–250 nmol·L⁻¹) in 66% of the participants. These findings were verified in a subgroup of the study population during the subsequent summer. Participants who reported use of vitamin D supplements had higher initial concentrations (64.2 ± 20.1 nmol·L⁻¹) compared to nonusers (53.7 ± 21.7 nmol·L⁻¹; P=0.04). Further, 25[OH]D values correlated negatively with fat mass (kg) prior to summer only in the female population (r=−0.29,  P=0.008).

Conclusions

In the present study, sun exposure had a beneficial but insufficient effect on 25[OH]D levels, and the same levels were documented in two consecutive summer seasons, confirming that vitamin D supplementation in both summer and winter should be considered in this population.

Perceived benefits and barriers of walking among overweight and obese adults

The current study aimed to explore perceived barriers and benefits of walking of overweight and obese adults. Fifteen face-to-face, semistructured interviews were conducted. Content and thematic analyses were used. Findings revealed that informants were aware of more benefits from walking than barriers. Gaining health and fitness, losing weight, the opportunity to walk in a group, and setting goals and sharing achievements were more sited benefits of walking. Confusion about walking guidelines and walking location perceived as barriers to walking. The findings of this study would be applied to develop walking intervention.

Diets along with interval training regimes improves inflammatory & anti-inflammatory condition in obesity with type 2 diabetes subjects

Background

Different physical activities and diets change the regulation of inflammations in both type 2 diabetes (T2D) patients and obese individuals, but the effect of both (Physical activity and diet) on pro/anti-inflammations has remained unknown. We investigated pro/anti-inflammations control, cardiovascular function, and total physiological parameters before and after 24 weeks of low volume high intensity interval training (HIIT) on a cycle ergometer along with four dietary regimes in obesity with T2D patients.

Methods

33 non-active obesity T2D patients (BMI ≥ 30) midges (47 yrs. ± 5) were volunteered to participate and randomly divided into three experimental(n = 11) [(1) LCD = low Carbohydrate Diet, (2) LFD = Low Fat Diet and (3) HFD = High Fat Diet)] and one control (n = 9) [ND = normal diet] groups. The whole groups performed underwent 8-week dietary regimes and then performed 3 days/weeks (3 set 10 × 60 s) HIIT on a cycle ergometer for 12 weeks, which followed by a 4-week diet period again. Also, prior to and after 8 weeks diet-12 weeks High Intensity Interval Training (HIIT) and 4 weeks diet 2-h oral glucose tolerance test (OGTT), resting blood pressure, incremental maximal oxygen uptake (VO2peak) cycle ergometer test and blood sample was collected from the subjects in order to measure pro/anti-inflammatory cytokines (IL-6, TNF-α, leptin, resistin, adiponectin, and FGF21).

Results

After 24 weeks of intervention, the results indicated that the highest improvement in the percentage of changes in glucose happened in LCD (-34.76), insulin in ND (+16.43), cholesterol in LCD (-33.35), LDL in LFD (-9.14), HDL in LCD (+41.81), TG in LCD (-40.71), weight in LCD (-12.49) and HOMA-IR in HFD (-6.82). The results also indicated that after 24 weeks of HIIT and diet interventions, highest benefit percentage change IL-6, resistin and leptin occurred in LCD (-32.10, -28.29 and - 53.92, respectively), TNF-α, FGF21 and adiponectin in LFD (-48.06, +55.30 and + 42.32, respectively). However, these changes were observed in other groups.

Conclusions

These results demonstrated that HIIT along with low carbohydrate regimes improves overall cardiovascular parameters and reduce pro-inflammatory markers and increase anti-inflammatory markers in type 2 diabetic patients. Additionally, as with HIIT along with low carbohydrate, HIIT coupled with low fat would improve inflammation markers, though these effects were less significant. These findings suggest that HIIT along with low carbohydrate is a beneficial exercise and dietary strategy in T2D patients.

The role of physical activity in the development of first cardiovascular disease event: a tree-structured survival analysis of the Danish ADDITION-PRO cohort

Background

Ambiguity exists in relation to the role of physical activity (PA) for cardiovascular disease (CVD) risk reduction. We examined the interplay between PA dimensions and more conventional CVD risk factors to assess which PA dimensions were associated with the first CVD event and whether subgroup differences exist.

Methods

A total of 1449 individuals [median age 65.8 (IQR: 61.2, 70.7) years] with low to high risk of type 2 diabetes and free from CVD from the Danish ADDITION-PRO study were included for survival analysis. PA was measured by individually calibrated heart rate and movement sensing for 7 consecutive days. The associations of different PA dimensions (PA energy expenditure, time spent in light-, moderate- and vigorous intensity PA), sedentary time and other conventional CVD risk factors with the first CVD event were examined by tree-structured survival analysis. Baseline information was linked to data on the first CVD event (ischemic heart disease, ischemic stroke, heart failure, atrial flutter/fibrillation and atherosclerotic disease) and mortality obtained from Danish registers.

Results

During a median follow-up time of 5.5 (IQR: 5.1–6.1) years, a total of 201 individuals (13.9%) developed CVD. Overall CVD incidence rate was 2.6/100 person-years. PA energy expenditure above 43 kJ/kg/day was associated with lower rates of CVD events among participants ≤ 70 years and with HbA_1c ≤ 5.7% (39 mmol/mol), systolic blood pressure ≤ 156 mmHg and albumin creatinine ratio ≤ 70 (incidence rates 0.0–0.8/100 person-years).

Conclusions

Any type of PA resulting in increased PA energy expenditure may over time be the best prevention strategy to uphold reduced risk of CVD.

Electronic supplementary material

The online version of this article (10.1186/s12933-018-0769-x) contains supplementary material, which is available to authorized users.

Self-directed exercise programmes in sedentary middle-aged individuals in good overall health; a systematic review

Many chronic diseases and illnesses are caused by the lifestyle, including the physical activity habits, of an individual. As such, consistent high levels of exercise should be encouraged across the lifespan, to limit the risk of developing one of these conditions and allowing for healthy aging to occur. Exercise prescriptions that encourage high completion and adherence rates in an independent manner and improve health related outcomes should be provided to individuals. To date, no review has identified optimal prescriptions of exercise to achieve this in sedentary middle-aged adults and this is important, given the higher risk of developing illnesses in this population as they age. This review examines the effects prescriptions of self-directed (SD) exercise has on adherence and health related outcomes in sedentary middle-aged individuals in good general health currently and aims to identify the most suitable forms of planned SD exercise that can be carried out independently. A systematic search of the electronic database PubMed was conducted. Randomised controlled trials published in English between February 2007 and February 2017 examining healthy, sedentary middle-aged participants only were included. Studies were critically appraised using the PEDro scale and data were presented on standardised tables. Twenty-one articles examining different aerobic activities, combined training and non-traditional exercise prescriptions were included. This review summarised in detail the effects SD exercise interventions had on sedentary middle-aged individuals alongside the adherence to the prescriptions. SD exercise was seen to be beneficial for improving metabolic outcomes physical characteristics, cardiorespiratory fitness and functional measures.

Exercise training modalities in patients with type 2 diabetes mellitus: a systematic review and network meta-analysis

INTRODUCTION

Current international guidelines recommend aerobic, resistance, and combined exercises for the management of type 2 diabetes mellitus (T2DM). In our study, we conducted a network meta-analysis to assess the comparative impact of different exercise training modalities on glycemic control, cardiovascular risk factors, and weight loss in patients with T2DM.

METHODS

We searched five electronic databases to identify randomized controlled trials (RCTs) that compared the differences between different exercise training modalities for patients with T2DM. The risk of bias in the included RCTs was evaluated according to the Cochrane tool. Network meta-analysis was performed to calculate mean difference the ratio of the mean and absolute risk differences. Data were analyzed using R-3.4.0.

RESULTS

A total of 37 studies with 2208 patients with T2DM were included in our study. Both supervised aerobic and supervised resistance exercises showed a significant reduction in HbA1c compared to no exercise (0.30% lower, 0.30% lower, respectively), however, there was a less reduction when compared to combined exercise (0.17% higher, 0.23% higher). Supervised aerobic also presented more significant improvement than no exercise in fasting plasma glucose (9.38 mg/dl lower), total cholesterol (20.24 mg/dl lower), triacylglycerol (19.34 mg/dl lower), and low-density lipoprotein cholesterol (11.88 mg/dl lower). Supervised resistance showed more benefit than no exercise in improving systolic blood pressure (3.90 mmHg lower]) and total cholesterol (22.08 mg/dl lower]. In addition, supervised aerobic exercise was more powerful in improving HbA1c and weight loss than unsupervised aerobic (HbA1c: 0.60% lower; weight loss: 5.02 kg lower) and unsupervised resistance (HbA1c: 0.53% lower) exercises.

CONCLUSION

Compared with either supervised aerobic or supervised resistance exercise alone, combined exercise showed more pronounced improvement in HbA1c levels; however, there was a less marked improvement in some cardiovascular risk factors. In terms of weight loss, there were no significant differences among the combined, supervised aerobic, and supervised resistance exercises.

TRIAL REGISTRATION

Our study protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO); registration number: CRD42017067518 .

The Effects of Nordic Walking and Slope of the Ground on Lower Limb Muscle Activity

Psurny, M, Svoboda, Z, Janura, M, Kubonova, E, Bizovska, L, Martinez Lemos, RI, and Abrantes, J. The effects of Nordic walking and slope of the ground on lower limb muscle activity. J Strength Cond Res 32(1): 217-222, 2018-Nordic walking (NW) has proven to be a simple and safe mode of exercise that can be used in various types of sport, recreation, and rehabilitation activities. The aim of this study was to assess the effect of Nordic walking and slope of the ground on lower limb muscle activity. The experimental group consisted of 22 healthy men (aged 22.8 ± 1.4 years). The subjects walked on a treadmill at a self-selected speed. Two walking conditions (NW and walking) and 2 ground slopes (level ground and uphill walking at an 8% incline) were used. The surface electromyographic signals of the gastrocnemius lateralis, tibialis anterior, vastus medialis, rectus femoris, biceps femoris and gluteus medius were recorded. Nordic walking resulted in increased activity of some lower limb muscles, particularly during the first half of the stance phase, and decreased muscle activity during the first half of the swing phase. Uphill walking elicited increased muscle activity compared with level walking, particularly during the stance phase and the second half of the swing phase during both walking and NW, and the change was more pronounced during walking. We concluded that NW increased muscle activity in the lower extremities compared with walking, particularly on level ground. Increasing the ground slope enhanced the muscle activity to a much greater extent than NW.

Effects of 12 weeks of Nordic Walking and XCO Walking training on the endurance capacity of older adults

BACKGROUND

Several studies have already examined the positive effects of various forms of endurance training in patient groups and in healthy adults up to 60 years old. The aim of this study was to analyse the effects of Nordic Walking (NW) and XCO Walking (XCO) training on endurance capacity in healthy older adults, aged 60 years and older.

METHODS

Twenty-three older participants (mean age: 69.9 ± 5.4 years) were randomly assigned to either the NW group or the XCO group. All participants were measured before and after the 12 weeks of endurance training (2 sessions/week) to examine oxygen uptake (VO₂) and energy consumption during an outdoor field test. In addition, heart rates were recorded and lactate samples were collected.

RESULTS

NW mainly demonstrated some significant (p < 0.05) decreases in heart rate, lactate concentration at lower to moderate walking speeds, whereas XCO Walking revealed significant (p < 0.05) decreases in lactate concentration and VO₂ at low to higher walking speeds.

CONCLUSIONS

NW as well as XCO training increase the efficiency of the cardio-vascular system in older subjects. Both training approaches are suitable options for endurance training, which may serve to counteract age- and inactivity-related decreases in cardio-vascular functioning as well as aid in maintaining overall performance in older adults.

Insulin sensitivity, body composition and adipose depots following 12 w combined endurance and strength training in dysglycemic and normoglycemic sedentary men

CONTEXT

Insulin resistance and dysglycemia are associated with physical inactivity and adiposity, and may be improved by exercise.

OBJECTIVE

Investigate the effect of exercise on insulin sensitivity, body composition and adipose depots in sedentary men with (n = 11) or without (n = 11) overweight and dysglycemia.

MATERIAL AND METHODS

Euglycemic-hyperinsulinemic clamp, ankle-to-neck MRI, MRS, muscle and adipose tissue biopsies before and after 12 weeks combined strength and endurance exercise.

RESULTS

Insulin sensitivity, VO₂max, strength, whole-body and muscle fat content, and abdominal adipose depots were improved without obvious differences between normo- and dysglycemic men. Hepatic fat, waist circumference and subcutaneous adipose tissue were reduced in the dysglycemic group. For both groups plasma adiponectin was reduced, whereas IL-6 was unchanged. Visceral fat was preferentially lost compared with other adipose depots.

DISCUSSION AND CONCLUSION

Body composition, fat distribution and insulin sensitivity improved following training in sedentary middle-aged men with and without dysglycemia.

Effects of Buddhist walking meditation on glycemic control and vascular function in patients with type 2 diabetes

OBJECTIVE

To investigate and compare the effects of Buddhist walking meditation and traditional walking on glycemic control and vascular function in patients with type 2 diabetes mellitus.

METHODS

Twenty three patients with type 2 diabetes (50-75 years) were randomly allocated into traditional walking exercise (WE; n=11) or Buddhism-based walking meditation exercise (WM; n=12). Both groups performed a 12-week exercise program that consisted of walking on the treadmill at exercise intensity of 50-70% maximum heart rate for 30min/session, 3 times/week. In the WM training program, the participants performed walking on the treadmill while concentrated on foot stepping by voiced "Budd" and "Dha" with each foot step that contacted the floor to practice mindfulness while walking.

RESULTS

After 12 weeks, maximal oxygen consumption increased and fasting blood glucose level decreased significantly in both groups (p<0.05). Significant decrease in HbA1c and both systolic and diastolic blood pressure were observed only in the WM group. Flow-mediated dilatation increased significantly (p<0.05) in both exercise groups but arterial stiffness was improved only in the WM group. Blood cortisol level was reduced (p<0.05) only in the WM group.

CONCLUSION

Buddhist walking meditation exercise produced a multitude of favorable effects, often superior to traditional walking program, in patients with type 2 diabetes.

The influence of a ten-week Nordic walking training-rehabilitation program on the level of lipids in blood in overweight and obese postmenopausal women

[Purpose] The aim of this study was to evaluate the effect of a ten-week Nordic Walking (NW) rehabilitation program on chosen anthropometric parameters and the level of basic lipids in overweight and obese postmenopausal women’s blood. [Subjects and Methods] The subjects were 32 women aged 50–68 (average: 59.7 ± 5.9 years). The study was carried out following a non-randomized model and entailed NW rehabilitation 5 times a week, which lasted for 10 weeks, as well as a low-calorie 1,500 kcal diet. The therapeutic results of the study were measured through changes in anthropometric and biochemical parameters. The results were subjected to a statistical analysis. [Results] After 10 weeks of NW rehabilitation it was observed that participants lost weight and their body mass index dropped. Additionally, whereas levels of total cholesterol, LDL and triglycerides dropped, and the level of HDL increased. [Conclusion] Rehabilitation carried out according to the NW model resulted in statistically significant changes in basic lipids in blood which, considerably increased the percentage of persons who achieved the recommended level of blood lipids. Obese persons were characterised by a smaller rehabilitation weight loss. More intense workouts and cooperation with a dietician are required.

Change in daily ambulatory activity and cardiovascular events in people with impaired glucose tolerance

Patients with pre-diabetes have a tenfold higher risk of developing Type 2 DM and a twofold higher risk of developing coronary heart disease compared to non-diabetics. Interventions targeted at those in an early stage of impaired glucose metabolism can delay or prevent diabetes. Effects of these interventions on cardiovascular outcome are unknown. This article aims to review current and available data on lifestyle intervention, specifically physical activity, on cardiovascular outcomes in populations at risk for diabetes. We searched PubMed database from 1990 to present with focus on more recent literature published over the last 2 years. Various permutations of keywords used included glucose intolerance, pre-diabetes, diabetes, lifestyle modifications, physical activity, and cardiovascular disease. Intensive glycemic control, specific medications, and lifestyle intervention including increase in physical activity have been evaluated in diabetes and pre-diabetes. Most studies we reviewed showed that these interventions prevented progression of pre-diabetes to diabetes and improved cardiovascular risk surrogate measures. Direct decrease in cardiovascular mortality, non-fatal stroke, and non-fatal myocardial infarctions was shown in one recent trial. Increase in physical activity has a positive effect on decreasing cardiovascular risk by modifying several important risk factors and may decrease risk of events in pre-diabetics. More randomized high power trials are needed to verify and characterize these effects.

Influence of physical activity and gender on arterial function in type 2 diabetes, normal and impaired glucose tolerance

To determine whether Nordic walking improves cardiovascular function in middle-aged women and men, we included 121 with normal glucose tolerance, 33 with impaired glucose tolerance and 47 with Type 2 diabetes mellitus in a randomized controlled study. The intervention group added Nordic walking 5 h/week for 4 months to their ordinary activities. Aortic pulse wave velocity, aortic augmentation index, stiffness index, reflection index, intima-media thickness in the radial and carotid arteries, echogenicity of the carotid intima-media and systemic vascular resistance were measured. While baseline blood pressure did not differ by gender or diagnosis, aortic augmentation index was found to be higher in women in all groups. Vascular function was unchanged with intervention, without differences by gender or diagnosis. In conclusion, 4 months of Nordic walking is an insufficient stimulus to improve vascular function. Future studies should consider hard endpoints in addition to measures of vascular health, as well as larger population groups, long-term follow-up and documented compliance to exercise training.

High Intensity Interval Training Improves Glycaemic Control and Pancreatic β Cell Function of Type 2 Diabetes Patients

Physical activity improves the regulation of glucose homeostasis in both type 2 diabetes (T2D) patients and healthy individuals, but the effect on pancreatic β cell function is unknown. We investigated glycaemic control, pancreatic function and total fat mass before and after 8 weeks of low volume high intensity interval training (HIIT) on cycle ergometer in T2D patients and matched healthy control individuals. Study design/method: Elderly (56 yrs±2), non-active T2D patients (n = 10) and matched (52 yrs±2) healthy controls (CON) (n = 13) exercised 3 times (10×60 sec. HIIT) a week over an 8 week period on a cycle ergometer. Participants underwent a 2-hour oral glucose tolerance test (OGTT). On a separate day, resting blood pressure measurement was conducted followed by an incremental maximal oxygen uptake (V˙O_2max) cycle ergometer test. Finally, a whole body dual X-ray absorptiometry (DXA) was performed. After 8 weeks of training, the same measurements were performed. Results: in the T2D-group, glycaemic control as determined by average fasting venous glucose concentration (p = 0.01), end point 2-hour OGTT (p = 0.04) and glycosylated haemoglobin (p = 0.04) were significantly reduced. Pancreatic homeostasis as determined by homeostatic model assessment of insulin resistance (HOMA-IR) and HOMA β cell function (HOMA-%β) were both significantly ameliorated (p = 0.03 and p = 0.03, respectively). Whole body insulin sensitivity as determined by the disposition index (DI) was significantly increased (p = 0.03). During OGTT, the glucose continuum was significantly reduced at -15 (p = 0.03), 30 (p = 0.03) and 120 min (p = 0.03) and at -10 (p = 0.003) and 0 min (p = 0.003) with an additional improvement (p = 0.03) of its 1^st phase (30 min) area under curve (AUC). Significant abdominal fat mass losses were seen in both groups (T2D: p = 0.004 and CON: p = 0.02) corresponding to a percentage change of -17.84%±5.02 and -9.66%±3.07, respectively. Conclusion: these results demonstrate that HIIT improves overall glycaemic control and pancreatic β cell function in T2D patients. Additionally, both groups experienced abdominal fat mass losses. These findings demonstrate that HIIT is a health beneficial exercise strategy in T2D patients.

Changes in gene expression in responders and nonresponders to a low-intensity walking intervention

OBJECTIVE

Daily physical activity remains an effective strategy to prevent obesity and type 2 diabetes. However, the metabolic response to exercise training is variable, and the precise clinical and molecular determinants that mark the metabolic improvements remain unknown. We tested the hypothesis that clinical improvements in glucose control after low-intensity exercise in individuals with impaired glucose tolerance (IGT) are coupled to alterations in skeletal muscle gene expression.

RESEARCH DESIGN AND METHODS

We investigated 14 overweight individuals with IGT before and after a 4-month low-intensity unsupervised walking exercise intervention. Clinical and anthropometric measurements and glucose tolerance were determined before and after the intervention. Skeletal muscle biopsy specimens were obtained for mRNA expression analysis.

RESULTS

Waist circumference and work capacity during cycle ergometry were improved in individuals who achieved normal glucose tolerance (NGT) after exercise training (IGT-NGT; n = 9) but in not individuals who remained IGT (IGT-IGT; n = 5). Pretraining glycemic control was better in IGT-NGT compared with IGT-IGT. mRNA expression of mitochondrial markers and transcription factors was increased in IGT-NGT after exercise intervention and normalized to levels measured in a separate cohort of nonexercised individuals with NGT. Conversely, these markers were unaltered after exercise intervention in IGT-IGT.

CONCLUSIONS

Normalization of metabolic control can be achieved after low-intensity exercise in individuals with IGT. This can be tracked with increased mRNA expression of mitochondrial and metabolic genes in skeletal muscle. However, for individuals presenting with a greater derangement in glycemia, the potential for clinical and metabolic improvements after this low-intensity unsupervised exercise protocol appears to be limited.

Effect of nordic walking and water aerobics training on body composition and the blood flow in lower extremities in elderly women

Nordic walking and water aerobics are very popular forms of physical activity in the elderly population. The aim of the study was to evaluate the influence of regular health training on the venous blood flow in lower extremities and body composition in women over 50 years old. Twenty-four women of mean age 57.9 (± 3.43) years, randomly divided into three groups (Nordic walking, water aerobics, and non-training), participated in the study. The training lasted 8 weeks, with one-hour sessions twice a week. Dietary habits were not changed. Before and after training vein refilling time and the function of the venous pump of the lower extremities were measured by photoplethysmography. Body composition was determined by bioelectrical impedance. Eight weeks of Nordic walking training improved the venous blood flow in lower extremities and normalized body composition in the direction of reducing chronic venous disorder risk factors. The average values of the refilling time variable (p = 0.04, p = 0.02, respectively) decreased in both the right and the left leg. After training a statistically significant increase in the venous pump function index was found only in the right leg (p = 0.04). A significant increase in fat-free mass, body cell mass and total body water was observed (p = 0.01), whereas body mass, the body mass index, and body fat decreased (p < 0.03). With regard to water aerobic training, no similar changes in the functions of the venous system or body composition were observed.

Association of the ACTN3 R577X polymorphism with glucose tolerance and gene expression of sarcomeric proteins in human skeletal muscle

A common polymorphism (R577X) in the α-actinin (ACTN) 3 gene, which leads to complete deficiency of a functional protein in skeletal muscle, could directly influence metabolism in the context of health and disease. Therefore, we tested the hypothesis that states of glucose tolerance are associated with the ACTN3 R577X genotype. We analyzed the prevalence of the ACTN3 R577X polymorphism in people with normal glucose tolerance (NGT) and type 2 diabetes (T2D) and measured muscle-specific α-actinin 2 and 3 mRNA and protein abundance in skeletal muscle biopsies. Furthermore, we investigated the protein abundance of the myosin heavy chain isoforms and the components of the mitochondrial electron transport chain in skeletal muscle from people with NGT or T2D. mRNA of selected sarcomeric z-disk proteins was also assessed. Although the prevalence of the ACTN3 577XX genotype was higher in T2D patients, genotype distribution was unrelated to metabolic control or obesity. ACTN2 and ACTN3 mRNA expression and protein abundance was unchanged between NGT and T2D participants. Protein abundance of mitochondrial complexes II and IV was related to genotype and glucose tolerance status. Gene expression of sarcomeric z-disk proteins was increased in skeletal muscle from NGT participants with the ACTN3 577XX genotype. While genetic variation in ACTN3 does not influence metabolic control, genotype does appear to influence gene expression of other sarcomeric proteins, which could contribute to the functional properties of skeletal muscle and the fatigue-resistant phenotype associated with the R577X polymorphism.

A healthy diet with and without cereal grains and dairy products in patients with type 2 diabetes: study protocol for a random-order cross-over pilot study--Alimentation and Diabetes in Lanzarote--ADILAN

Background

Research on the role of nutrition in type 2 diabetes has largely focused on macro/micronutrient composition and dietary fiber intake, while fewer studies have tested the effects of differing food choice. Some observational studies and short-term intervention studies suggest that a food pattern mimicking the diet with which humans evolved positively influences glucose control and associated endocrine systems. Such a food pattern mainly differs from other common healthy food patterns in its absence of cereal grains and dairy products. The primary aim of this pilot study is to determine the effect of two healthy diets with or without cereal grains and dairy products on glucose control, while keeping participants’ weight stable and other food parameters, such as macro/micronutrient composition, dietary fiber and glycemic load, the same in both diets.

Methods/Design

We intend to include 15 adult patients with a medical diagnosis of type 2 diabetes mellitus with or without medication and with an increased waist circumference (≥ 80 cm for women and ≥ 94 cm for men) in a random-order cross-over diet intervention study during two periods of four-weeks separated by a six-week washout period. Patients will be instructed to eat two healthy diets according to official dietary guidelines with respect to macro/micronutrient composition and fiber content, but differing in the type of food included, with one diet being without cereal grains and dairy products. Lunch will be served in a hospital kitchen for control of nutrient intake, while the rest of the meals will be eaten at home according to specific directions. The energy content of the diets will be individually adjusted to maintain a stable body weight during the two four-week intervention periods. Primary outcomes will be change in fasting plasma glucagon and fructosamine, while secondary outcomes include change in fasting glucose and glycated hemoglobin, glucose and glucagon response during oral glucose tolerance test, blood lipids, blood pressure, C-reactive protein, body composition, quality of life, subjective experience with the two diets, satiety scores and changes in medication.

Discussion

Using these results, we will assess the need to conduct larger and longer studies with similar design.

Trial registration

This trial was registered at clinicaltrials.gov as NCT01891955 and Spanish Agency of Medication and Sanitary Products (AEMPS) registration code: MFV-ADI-2013-01.

Sestrin 3 regulation in type 2 diabetic patients and its influence on metabolism and differentiation in skeletal muscle

In mammals, the sestrin family is composed of three stress-responsive genes. Ablation of sestrin in Drosophila attenuates longevity, which is accompanied by increased S6K phosphorylation and decreased AMPK phosphorylation. Nevertheless, the metabolic role of sestrins in mammals is not comprehensively understood. We characterized the expression of individual sestrin family members and determined their role in vastus lateralis muscle biopsies from participants with normal glucose tolerance (NGT) or type 2 diabetes (T2D). Expression of sestrin 1 or sestrin 2 mRNA was unaltered between the NGT and T2D participants. Conversely, sestrin 3 mRNA was increased in T2D patients and correlated with fasting plasma glucose, 2-h postprandial plasma glucose and HbA1c. A trend for increased sestrin 3 protein was observed in T2D patients. In human primary myotubes, sestrin 3 mRNA increased during differentiation, and this response was unaltered in T2D-derived myotubes. Long-term treatment of myotubes with insulin or AICAR decreased sestrin 3 mRNA. Exposure of myotubes to the reactive oxygen species H2O2 increased mRNA expression of sestrin 1 and 2, whereas sestrin 3 was unaltered. siRNA-mediated silencing of sestrin 3 in myotubes was without effect on insulin-stimulated glucose incorporation into glycogen or AICAR-stimulated palmitate oxidation. These results provide evidence against sestrin 3 in the direct control of glucose or lipid metabolism in human skeletal muscle. However, siRNA-mediated sestrin 3 gene silencing in myotubes increased myostatin expression. Collectively, our results indicate sestrin 3 is upregulated in T2D and could influence skeletal muscle differentiation without altering glucose and lipid metabolism.

The effect of walking with poles on the distribution of plantar pressures in normal subjects

BACKGROUND

Elevated pressures on the plantar surface of the foot increases the potential of developing foot ulcers in patients who are at risk. Walking with poles has been shown to reduce ground reaction and joint forces; however, the effect on plantar pressures is unknown.

OBJECTIVE

To determine the effectiveness of walking with poles on reducing plantar pressure on the foot after brief instructions and 1 week of self-guided practice. It was hypothesized that there would be a significant reduction in pressure in the foot when walking with poles.

DESIGN

This was a nonblinded, randomized, crossover study.

SETTING

This study took place in a motion analysis laboratory located at an academic institution.

METHODS

Thirty-five healthy subjects were instructed on 2 gait patterns when using walking poles. When walking with the 2-point pattern, the subjects placed the poles of the opposite side with the foot in stance. The 3-point pattern required the subjects to place both poles with the right foot. After 1 week of unsupervised practice, plantar pressures under the metatarsal heads and hallux of the right foot were measured by using a pedobarograph mat while walking with and without the poles.

MAIN OUTCOME MEASUREMENTS

Mean plantar pressures and impulses were recorded from 5 trials for each walking condition: no poles, 2-point, and 3-point styles.

RESULTS

Walking with the poles resulted in significant reductions (P ≤ .01) in mean and impulse of pressure under the metatarsal heads region of up to 24%; no significant changes were seen under the heel or hallux. The 3-point style resulted in a significantly greater reduction of pressure compared with the 2-point style (P = .002) in the metatarsal region but not the hallux.

CONCLUSIONS

Walking with poles was easy to learn and may be a useful part of the management of persons at risk for developing plantar foot ulcers.

Urgent call for the third wish

The people afflicted with obesity and its consequences need a menu of low-cost programmes to mitigate the over-nutrition and under-activity that underlie their condition. This editorial commentary points out the multiple merits (and shortcomings) of the Nordic walking - with ski poles - presented in an accompanying article. The Nordic exercise programme is then examined more broadly in the context of the general principles and limitations of exercise programmes - with and without calorie control - as a guide to future innovations.