A Comparative Study of Health Efficacy Indicators in Subjects with T2DM Applying Power Cycling to 12 Weeks of Low-Volume High-Intensity Interval Training and Moderate-Intensity Continuous Training

Effects of exercise training and physical activity advice on HbA1c in people with type 2 diabetes: A network meta-analysis of randomized controlled trials

AIMS

To compare the magnitude of the benefit of different exercise modalities on glycemic control, including aerobic training (AT), resistance training (RT), combined training (CT), high-intensity interval training (HIIT) and physical activity advice.

METHODS

A network meta-analysis was conducted. Seven databases were searched from inception to May 2024. We included randomized clinical trials of at least 12 weeks' duration evaluating different types of physical exercise and physical activity advice to reduce HbA1c in people with type 2 diabetes.

RESULTS

158 studies (17,059 participants) were included. Compared with the control group, all types of exercise were associated with lower HbA1c: HIIT [-0.61 % (95 % CrI -0.84; -0.37)], CT [-0.58 % (95 % CrI -0.73; -0.42], AT [-0.58 % (95 % CrI -0.70; -0.45)], RT [-0.40 % (95 % CrI -0.59; -0.21)] and physical activity advice [-0.35 % (95 % CrI -0.53; -0.16)]. HIIT was the most effective treatment for HbA1c reduction (SUCRA = 82 %), followed by CT (SUCRA = 77 %), AT (SUCRA = 76 %), RT (SUCRA = 37 %) and physical activity advice (SUCRA = 29 %).

CONCLUSIONS

HIIT was associated with the greatest reduction in HbA1c. Physical activity advice, which is easy to implement, accessible and unsupervised, should also be offered to people with type 2 diabetes to improve glycemic control.

The Effectiveness of High-Intensity Interval Training vs. Cardio Training for Weight Loss in Patients with Obesity: A Systematic Review

Background: Obesity is a growing public health issue, increasing the risk of metabolic disorders and cardiovascular diseases. Physical activity is a key factor in obesity treatment; however, the effectiveness of different exercise modalities remains unclear, especially considering age-related physiological differences. High-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) are two commonly recommended strategies, but their impact on fat reduction across different age groups has not been thoroughly analyzed. This study aims to determine which training modality is most effective for fat reduction in individuals with obesity, considering age as a crucial factor in exercise response. Methods: A systematic review was conducted, analyzing studies published between 2014 and 2024. The inclusion criteria focused on the studies comparing HIIT and MICT effects on body composition in obese individuals of different age groups. The data extraction included training protocols, fat mass reduction, and adherence levels. The primary outcomes measured changes in body fat percentage and muscle mass retention. Results: HIIT was found to be most effective for younger individuals (18-30 years), promoting fat oxidation and muscle retention. In middle-aged adults (31-40 years), both HIIT and MICT yielded similar benefits, with MICT preferred due to better adherence. In older adults (41-60 years), MICT provided a more sustainable strategy for fat reduction and muscle preservation. However, the variability across the studies limits definitive conclusions. Conclusions: Age influences the effectiveness of HIIT and MICT for obesity treatment, highlighting the need for age-specific exercise recommendations. Future studies should standardize training protocols and assess long-term metabolic adaptations to optimize physical activity guidelines.

Physiological Mechanisms Driving Microcirculatory Enhancement: the Impact of Physical Activity

Background

Physical activity induces many beneficial adaptive changes to blood vessel microcirculation, ultimately improving both health and exercise performance. This positions it an effective non-pharmacological therapeutic approach for the rehabilitation of patients with various chronic diseases. Understanding the impact of different types of physical activities on microcirculation and elucidating their physiological mechanisms is crucial for optimizing clinical practice.

Methods

A comprehensive literature search was performed across multiple databases including PubMed, EBSCO, ProQuest, and Web of Science. Following a rigorous screening process, 48 studies were selected for inclusion into the study.

Results

Existing studies demonstrate that various forms of physical activity facilitate multiple positive adaptive changes at the microcirculation level. These include enhanced microvascular dilation-driven by endothelial cell factors and mechanical stress on blood vessels-as well as increased capillary density. The physiological mechanisms behind these improvements involve the neurohumoral regulation of endothelial cell factors and hormones, which are crucial for these positive effects. Physical activity also ameliorates inflammation markers and oxidative stress levels, upregulates the expression of silent information regulator 2 homolog 3, genes for hypoxia-inducible factors under hypoxic conditions, and induces favorable changes in multiple hemodynamic and hemorheological parameters. These structural and functional adaptations optimize myocardial blood flow regulation during exercise and improve both oxygen transport and utilization capacity, which are beneficial for the rehabilitation of chronic disease patients.

Conclusions

Our provides a reference for using physical activity as a non-pharmacological intervention for patients with chronic conditions. This framework includes recommendations on exercise types, intensity, frequency, and duration. Additionally, we summarize the physiological mechanisms through which physical activity improves microcirculation, which can inform clinical decision-making.

Effects of practical models of low-volume high-intensity interval training on glycemic control and insulin resistance in adults: a systematic review and meta-analysis of randomized controlled studies

Objectives

The aim of this systematic review and meta-analysis was to investigate the effects of practical models of low-volume high-intensity interval training protocols (LV-HIIT) on glucose control and insulin resistance compared with moderate-intensity continuous training (MICT) protocols and no-exercise controls (CON).

Methods

Four databases (PubMed, Web of Science, Scopus, and Cochrane Library) were searched for randomized controlled studies conducted using LV-HIIT interventions (HIIT/SIT protocols involving ≤ 15 min of intense training, within a session lasting ≤ 30 min; < 30 s all-out sprint for SIT additionally). The inclusion criteria required glucose and insulin resistance markers to be evaluated pre- and post-intervention among adults who were not trained athletes.

Results

As a result, twenty studies were included, and meta-analyses were conducted using sixteen studies employing HIIT protocols. Compared with CON, LV-HIIT with reduced intensity and extended interval duration significantly improved fasting glucose (FPG) (mean difference (MD) in mg/dL=-16.63; 95% confidence interval (CI): -25.30 to -7.96; p<0.001) and HbA1c (MD=-0.70; 95% CI: -1.10 to -0.29; p<0.001). Greater improvements were found in participants who were overweight/obese or having type 2 diabetes (T2D). FPG decreased with every additional second of interval duration (β;=-0.10; 95% CI: -0.19 to -0.00; p=0.046). FPI (β;=-0.65; 95% CI: -1.27 to -0.02; p=0.042) and HOMA-IR (β;=-0.22; 95% CI: -0.36 to -0.09; p=0.001) decreased with every additional minute of interval duration per session. HOMA-IR also decreased with every additional minute of weekly interval duration (β;=-0.06; 95%CI: -0.08 to -0.04; p<0.001). Compared with MICT, LV-HIIT was more effective in improving insulin sensitivity (SMD=-0.40; 95%CI: -0.70 to -0.09; p=0.01), but there were no differences in FPG, FPI, HbA1c or HOMA-IR (p>0.05). The effect of LV-HIIT on FPI was larger compared with MICT among individuals who lost weight.

Conclusion

Conclusively, a practical model of LV-HIIT with reduced intensity and extended interval was effective in improving glucose control and its effects were similar to MICT. Greater improvements were found in individuals with overweight/obesity or T2D in protocols with longer intervals or accumulated interval duration per session/week. More large-scale, randomized controlled studies with similar intervention protocols in a wide range of population are warranted to confirm these important results.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024516594.

Interventions and behaviour change techniques for improving physical activity level in working-age people (18-60 years) with type 2 diabetes: A systematic review and network meta-analysis

BACKGROUND

The escalating prevalence of type 2 diabetes within the working-age population (18-60 years) imposes a substantial societal burden. Whilst physical activity is crucial for diabetes management, limited evidence exists to inform optimal strategies for promoting physical activity in this population. We aimed to evaluate and compare the effect of interventions for increasing physical activity in working-age adults with type 2 diabetes.

METHODS

We searched Web of Science, the Cochrane Library, Medline, Embase, PsycINFO, ClinicalTrials.gov, and ICTRP from inception to April 30, 2023. Randomised controlled trials that reported the effect of interventions (education, training or behavioural) to promote physical activity (either self-reported or objective) in people aged 18-60 years were included. Two independent reviewers conducted summary data extraction and quality assessment. Pairwise random-effects, Frequentist network meta-analyses, and subgroup analysis were used to obtain pooled effects.

RESULTS

A total of 52 trials were included in this systematic review. Compared to control group, the physical activity interventions demonstrated statistically significant effects on objectively measured physical activity (SMD 0.77, 95 % CI 0.27-1.27), self-reported physical activity (SMD 0.88, 95 % CI 0.40-1.35), and overall physical activity (SMD 0.82, 95 % CI 0.48-1.16); a statistically and clinically meaningful reduction on glycated haemoglobin A1c (HbA1c) was also identified (MD -0.50 %, 95 % CI -0.66, -0.35). In terms of intervention types, education interventions exerted the largest effect on objectively measured physical activity; however, psychological interventions had the largest effects on overall physical activity compared to other intervention types. Four behaviour change techniques were related to statistically significant reduction in HbA1c: goal setting (outcome), information about health consequences, demonstration of the behaviour, and prompts/cues. Subgroup analysis showed that delivery mode, intervention setting, and facilitator were associated with statistically significant effect on physical activity and HbA1c.

CONCLUSIONS

Psychologically modelled education incorporating behaviour change techniques may be the most beneficial way to promote physical activity and glycaemic control in working-age adults with type 2 diabetes. Delivery mode, intervention setting, and facilitator type should be considered when designing interventions for improving physical activity level in working-age people with type 2 diabetes.

Characteristics of High-Intensity Interval Training Influence Anthropometrics, Glycemic Control, and Cardiorespiratory Fitness in Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Exercise is a non-pharmacological intervention for type 2 diabetes mellitus (T2DM), including moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT). Despite diverse exercise protocol variations, the impact of these variations in HIIT on T2DM anthropometrics, glycemic control, and cardiorespiratory fitness (CRF) remains unclear.

OBJECTIVE

The aim was to examine the influence of HIIT protocol characteristics on anthropometrics, glycemic control, and CRF in T2DM patients and compare it to control (without exercise) and MICT.

METHODS

This review is registered in PROSPERO (CRD42021281398) and follows Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search, employing "high-intensity interval training" and "diabetes mellitus" in PubMed and Web of Science databases, with a "randomized controlled trial" filter, spanned articles up to January 2023.

RESULTS

Of 190 records, 29 trials were included, categorized by HIIT interval duration, training volume, and intervention period. Long-duration, high-volume, and long-term HIIT yields superior outcomes compared to control conditions for body mass, waist circumference, fasting plasma glucose, Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), glycosylated hemoglobin (%HbA1c), and CRF. The findings favored HIIT over MICT for body mass in long-duration, high-volume, and short-term intervals (mean difference [MD] - 3.45, - 3.13, and - 5.42, respectively, all p < 0.05) and for CRF in long and medium work intervals and high volume (MD 1.91, 2.55, and 2.43, respectively, all p < 0.05), as well as in medium and long-term intervention (MD 2.66 and 2.21, respectively, all p < 0.05). Regardless of specific HIIT characteristics, no differences were found in the HIIT versus MICT comparison for glycemic control.

CONCLUSIONS

Specific HIIT protocol characteristics influence changes in anthropometrics, glycemic control, and CRF compared to control groups. However, compared to MICT, only longer duration, higher volume, and short-term HIIT improved body mass, waist circumference, and CRF in individuals with T2DM.

Glycaemic Response to Acute Aerobic and Anaerobic Exercise Performed in the Morning or Afternoon in Healthy Subjects: A Crossover Trial

BACKGROUND

The regular practice of physical activity is considered a health promoter and appears to be one of the main contributors to the prevention of chronic diseases. However, the potential effects of exercise on health depending on the time of day at which it is performed have not yet been fully elucidated.

OBJECTIVES

To evaluate the effect of physical exercise (aerobic or anaerobic) and chronobiology (morning or afternoon) on the glycemic metabolism of healthy subjects.

METHODS

Healthy subjects participated in aerobic or anaerobic physical exercise sessions, either in the morning or in the afternoon. Blood was drawn from the subjects before, at the end of the exercise and 2 hours after the end of the exercise. Glycemic parameters were analyzed at these time points. A general linear model test was performed after verifying the normal distribution of the raw data (as assessed by the Shapiro-Wilk test) or after a logarithmic/square root transformation, considering aerobic or anaerobic exercise and morning or afternoon exercise as independent variables.

RESULTS

Twenty-three subjects (14 women and 9 men) were included in the study. The rate of change in glucose levels was significantly higher at the end of anaerobic exercise compared to aerobic exercise (1.19 ± 0.04 vs. 0.98 ± 0.02, respectively), with a more pronounced decrease in insulin and C-peptide levels following aerobic exercise. In addition, the increase of glucose was higher after the exercise in the morning compared with the afternoon (1.14 ± 0.03 vs. 1.03 ± 0.03, respectively).

CONCLUSIONS

The type of exercise and chronobiology influence short-term glucose metabolism.

The Force Awakening in HbA1c Control: A Systematic Review and Meta-Analysis on the Efficacy of High-Intensity and Endurance Exercise in Patients With Type 2 Diabetes Mellitus

The increase in the global prevalence of type 2 diabetes mellitus (DM2), driven mainly by obesity and physical inactivity, has increased interest in various nonpharmacological therapies. This systematic review aims to establish the effectiveness of high-intensity interval training (HIIT) and resistance exercise (RE) compared with continuous aerobic exercise in improving control in patients with DM2. We conducted a comprehensive search for clinical trials using databases such as MEDLINE (PubMed) and Web of Science. The search was performed using a controlled vocabulary (MeSH) together with Boolean operators, and the results were limited to English and Spanish. Secondary outcomes were improvements in VO2max and decreases in low-density lipoprotein (LDL). This study aims to explain evidence-based recommendations for primary care physicians on exercise therapies to improve glycemic management as well as cardiovascular health in people with DM2.

Effects of high-intensity intermittent exercise on glucose and lipid metabolism in type 2 diabetes patients: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effects of high-intensity interval training (HIIT) on glycolipid metabolism among type 2 diabetes patients.

METHODS

HIIT is consistent with an exercise program (65%-90%VO2max or 75%-95% HRmax; exercise cycle≥2 weeks; frequency ≥ 2 times/week). A meta-analysis was conducted utilizing the random effects model to synthesize the data.

RESULTS

A total of 22 RCT studies with 1034 diabetic patients were included. Compared to moderate-intensity aerobic exercise or conventional controls, HIIT yields noteworthy effects on FBG (MD: -0.55; 95% CI: -0.85- -0.25, Hedges' g =0.98), 2h-PG (MD: -0.36; 95% CI: -0.57- -0.14, Hedges' g =1.05), FINS (MD: -0.41; 95% CI: -0.79- -0.03, Hedges' g =1.07), HbA1c (MD: -0.60; 95% CI: -0.84- -0.36, Hedges' g =2.69), TC (MD: -0.58; 95% CI: -0.80- -0.36, Hedges' g =2.36), TG (MD: -0.50; 95% CI: -0.86- -0.14, Hedges' g =1.50), HDL (MD: 0.62; 95% CI: 0.29-0.95, Hedges' g =1.19) and LDL (MD: -0.31; 95% CI: -0.56- -0.08, Hedges' g =0.91), all of the above p<0.01.

CONCLUSIONS

HIIT has been shown to improve glucose and lipid metabolism in patients with type 2 diabetes, especially in HbA1c, TC, TG, and HDL. For patients between the ages of 40 and 60 with less than 5 years of disease, exercise programs of moderate to longer duration or moderate to high intensity will produce more favorable results.

Effect of 5:2 Regimens: Energy-Restricted Diet or Low-Volume High-Intensity Interval Training Combined With Resistance Exercise on Glycemic Control and Cardiometabolic Health in Adults With Overweight/Obesity and Type 2 Diabetes: A Three-Arm Randomized Controlled Trial

OBJECTIVE

We aimed to examine the effects of a 5:2 diet (2 days per week of energy restriction by formula diet) or an exercise (2 days per week of high-intensity interval training and resistance training) intervention compared with routine lifestyle education (control) on glycemic control and cardiometabolic health among adults with overweight/obesity and type 2 diabetes.

RESEARCH DESIGN AND METHODS

This two-center, open-label, three-arm, parallel-group, randomized controlled trial recruited 326 participants with overweight/obesity and type 2 diabetes and randomized them into 12 weeks of diet intervention (n = 109), exercise intervention (n = 108), or lifestyle education (control) (n = 109). The primary outcome was the change of glycemic control measured as glycated hemoglobin (HbA1c) between the diet or exercise intervention groups and the control group after the 12-week intervention.

RESULTS

The diet intervention significantly reduced HbA1c level (%) after the 12-week intervention (-0.72, 95% CI -0.95 to -0.48) compared with the control group (-0.37, 95% CI -0.60 to -0.15) (diet vs. control -0.34, 95% CI -0.58 to -0.11, P = 0.007). The reduction in HbA1c level in the exercise intervention group (-0.46, 95% CI -0.70 to -0.23) did not significantly differ from the control group (exercise vs. control -0.09, 95% CI -0.32 to 0.15, P = 0.47). The exercise intervention group was superior in maintaining lean body mass. Both diet and exercise interventions induced improvements in adiposity and hepatic steatosis.

CONCLUSIONS

These findings suggest that the medically supervised 5:2 energy-restricted diet could provide an alternative strategy for improving glycemic control and that the exercise regimen could improve body composition, although it inadequately improved glycemic control.

A Proactive Intervention Study in Metabolic Syndrome High-Risk Populations Using Phenome-Based Actionable P4 Medicine Strategy

The integration of predictive, preventive, personalized, and participatory (P4) healthcare advocates proactive intervention, including dietary supplements and lifestyle interventions for chronic disease. Personal profiles include deep phenotypic data and genetic information, which are associated with chronic diseases, can guide proactive intervention. However, little is known about how to design an appropriate intervention mode to precisely intervene with personalized phenome-based data. Here, we report the results of a 3-month study on 350 individuals with metabolic syndrome high-risk that we named the Pioneer 350 Wellness project (P350). We examined: (1) longitudinal (two times) phenotypes covering blood lipids, blood glucose, homocysteine (HCY), and vitamin D3 (VD3), and (2) polymorphism of genes related to folic acid metabolism. Based on personalized data and questionnaires including demographics, diet and exercise habits information, coaches identified 'actionable possibilities', which combined exercise, diet, and dietary supplements. After a 3-month proactive intervention, two-thirds of the phenotypic markers were significantly improved in the P350 cohort. Specifically, we found that dietary supplements and lifestyle interventions have different effects on phenotypic improvement. For example, dietary supplements can result in a rapid recovery of abnormal HCY and VD3 levels, while lifestyle interventions are more suitable for those with high body mass index (BMI), but almost do not help the recovery of HCY. Furthermore, although people who implemented only one of the exercise or diet interventions also benefited, the effect was not as good as the combined exercise and diet interventions. In a subgroup of 226 people, we examined the association between the polymorphism of genes related to folic acid metabolism and the benefits of folate supplementation to restore a normal HCY level. We found people with folic acid metabolism deficiency genes are more likely to benefit from folate supplementation to restore a normal HCY level. Overall, these results suggest: (1) phenome-based data can guide the formulation of more precise and comprehensive interventions, and (2) genetic polymorphism impacts clinical responses to interventions. Notably, we provide a proactive intervention example that is operable in daily life, allowing people with different phenome-based data to design the appropriate intervention protocol including dietary supplements and lifestyle interventions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43657-023-00115-z.

Effects of high-intensity interval training and its different protocols on lipid profile and glycaemic control in type 2 diabetes: A meta-analysis

This meta-analysis of randomised clinical trials aimed to compare the effects of high-intensity interval training (HIIT) and its different protocols versus moderate-intensity continuous training (MICT) and/or control on total cholesterol, HDL, LDL, triglycerides, HbA1c levels, and fasting glucose in individuals with type 2 diabetes mellitus (T2DM). The search strategy was performed in PubMed/MEDLINE, Cochrane CENTRAL, EMBASE, Web of Science, Sport DISCUS, and PEDro, until January 2023. A total of 31 studies (1092 individuals) were included. When compared to control, HIIT decreased total cholesterol by -0.31 mmol/L (95% CI -0.49; -0.12), LDL by -0.31 mmol/L (95% CI -0.49; -0.12), triglycerides by -0.27 mmol/L (95% CI -0.33; -0.2), HbA1c by -0.75% (95% CI -0.97; -0.53), fasting glucose by -1.15 mmol/L (95% CI -1.44; -0.86), and increased HDL by 0.24 mmol/L (95% CI 0.06; 0.42). No difference was found in the comparison between HIIT versus MICT for any of the outcomes analysed, however subgroup analysis showed that a moderate-interval (>30s to < 2 min) and moderate-term (>4 to < 12 weeks) HIIT protocol reduced total cholesterol, when compared to MICT. HIIT is able to improve lipid profile and glycaemic control in T2DM individuals, and specific protocols can be recommended for improving total cholesterol levels.

Effects of high-intensity interval training, moderate-intensity continuous training, and guideline-based physical activity on cardiovascular metabolic markers, cognitive and motor function in elderly sedentary patients with type 2 diabetes (HIIT-DM): a protocol for a randomized controlled trial

Background and objective

Sedentary behavior is of increasing concern in older patients with type 2 diabetes mellitus (T2DM) due to its potential adverse effects on cardiovascular health, cognitive function, and motor function. While regular exercise has been shown to improve the health of individuals with T2DM, the most effective exercise program for elderly sedentary patients with T2DM remains unclear. Therefore, the objective of this study was to assess the impact of high-intensity interval training (HIIT), moderate-intensity continuous training (MICT), and guideline-based physical activity programs on the cardiovascular health, cognitive function, and motor function of this specific population.

Methods

This study will be a randomized, assessor-blind, three-arm controlled trial. A total of 330 (1:1:1) elderly sedentary patients diagnosed with T2DM will be randomly assigned the HIIT group (10 × 1-min at 85-95% peak HR, intersperse with 1-min active recovery at 60-70% peak HR), MICT (35 min at 65-75% peak HR), and guideline-based group (guideline group) for 12 weeks training. Participants in the guideline group will receive 1-time advice and weekly remote supervision through smartphones. The primary outcomes will be the change in glycosylated hemoglobin (HbA1c) and brain-derived neurotrophic factor (BDNF) after 12-weeks. Secondary outcomes will includes physical activity levels, anthropometric parameters (weight, waist circumference, hip circumference, and body mass index), physical measurements (fat percentage, muscle percentage, and fitness rate), cardiorespiratory fitness indicators (blood pressure, heart rate, vital capacity, and maximum oxygen), biochemical markers (high-density lipoprotein, low-density lipoprotein, triglycerides, total cholesterol, and HbA1c), inflammation level (C-reactive protein), cognitive function (reaction time and dual-task gait test performance), and motor function (static balance, dynamic balance, single-task gait test performance, and grip strength) after 12 weeks.

Discussion

The objective of this study is to evaluate the effect of 12 weeks of HIIT, MICT, and a guideline-based physical activity program on elderly sedentary patients diagnosed with T2DM. Our hypothesis is that both HIIT and MICT will yield improvements in glucose control, cognitive function, cardiopulmonary function, metabolite levels, motor function, and physical fitness compared to the guideline group. Additionally, we anticipate that HIIT will lead to greater benefits in these areas. The findings from this study will provide valuable insights into the selection of appropriate exercise regimens for elderly sedentary individuals with T2DM.

Ethics and dissemination

This study has been approved by the Ethics Review Committee of the Reproductive Hospital Affiliated with China Medical University (approval number: 202203). Informed consent will be obtained from all participants or their guardians. Upon completion, the authors will submit their findings to a peer-reviewed journal or academic conference for publication.

Clinical trial registration

Chinese Clinical Trial Registry, identifier ChiCTR2200061573.

Effectiveness of high intensity interval training on cardiorespiratory fitness and endothelial function in type 2 diabetes: A systematic review

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a chronic metabolic syndrome characterized by insulin resistance and hyperglycemia that may lead to endothelial dysfunction, reduced functional capacity and exercise intolerance. Regular aerobic exercise has been promoted as the most beneficial non-pharmacological treatment of cardiovascular diseases. High intensity interval training (HIIT) seems to be superior than moderate-intensity continuous training (MICT) in cardiovascular diseases by improving brachial artery flow-mediated dilation (FMD) and cardiorespiratory fitness to a greater extent. However, the beneficial effects of HIIT in patients with T2DM still remain under investigation and number of studies is limited.

AIM

To evaluate the effectiveness of high intensity interval training on cardiorespiratory fitness and endothelial function in patients with T2DM.

METHODS

We performed a search on PubMed, PEDro and CINAHL databases, selecting papers published between December 2012 and December 2022 and identified published randomized controlled trials (RCTs) in the English language that included community or outpatient exercise training programs in patients with T2DM. RCTs were assessed for methodological rigor and risk of bias via the Physiotherapy Evidence Database (PEDro). The primary outcome was peak VO2 and the secondary outcome was endothelial function assessed either by FMD or other indices of microcirculation.

RESULTS

Twelve studies were included in our systematic review. The 12 RCTs resulted in 661 participants in total. HIIT was performed in 310 patients (46.8%), MICT to 271 and the rest 80 belonged to the control group. Peak VO2 increased in 10 out of 12 studies after HIIT. Ten studies compared HIIT with other exercise regimens (MICT or strength endurance) and 4 of them demonstrated additional beneficial effects of HIIT over MICT or other exercise regimens. Moreover, 4 studies explored the effects of HIIT on endothelial function and FMD in T2DM patients. In 2 of them, HIIT further improved endothelial function compared to MICT and/or the control group while in the rest 2 studies no differences between HIIT and MICT were observed.

CONCLUSION

Regular aerobic exercise training has beneficial effects on cardiorespiratory fitness and endothelial function in T2DM patients. HIIT may be superior by improving these parameters to a greater extent than MICT.

Exercise in the Prevention and Treatment of Type 2 Diabetes

Type 2 diabetes is a systemic, multifactorial disease that is a leading cause of morbidity and mortality globally. Despite a rise in the number of available medications and treatments available for management, exercise remains a first-line prevention and intervention strategy due to established safety, efficacy, and tolerability in the general population. Herein we review the predisposing risk factors for, prevention, pathophysiology, and treatment of type 2 diabetes. We emphasize key cellular and molecular adaptive processes that provide insight into our evolving understanding of how, when, and what types of exercise may improve glycemic control. © 2023 American Physiological Society. Compr Physiol 13:1-27, 2023.

The effect of low volume high-intensity interval training on metabolic and cardiorespiratory outcomes in patients with type 2 diabetes mellitus: A systematic review and meta-analysis

Aims

The present systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to investigate the effect of low volume high-intensity interval training (LVHIIT) on the metabolic and cardiorespiratory outcomes in patients with type 2 diabetes mellitus (T2DM).

Methods

Relevant articles were sourced from PubMed, EBSCO, Web of Science, Embase, and the Cochrane Library from inception to October 2022. The study search strategy and all other processes were implemented in accordance with the PRISMA statement.

Results

Five randomized controlled trials that satisfied the inclusion criteria were included in this meta-analysis. The LVHIIT group had significantly lower fasting blood glucose levels (RR= -1.21; 95% CI= -2.02- -0.40, p = 0.0032) and HbA1c levels (RR= -0.65; 95% CI= -1.06- -0.23, p = 0.002) and higher levels of insulin resistance indicator HOMA-IR (RR= -1.34; 95% CI = -2.59- -0.10, p = 0.03) than the control group. Moreover, our results show that LVHIIT can reduce body mass (RR = -0.94, 95% CI = -1.37- -0.51, p<0.0001) and body mass index (RR = -0.31, 95% CI = -0.47- -0.16, p<0.0001). LVHIIT had a better therapeutic effect on blood lipid metabolism, such as total cholesterol, high-density lipoprotein, low-density lipoprotein and triglycerides. However, the change in fasting insulin levels was not statistically significant (RR= -1.43; 95% CI = -3.46- 0.60, p =0.17). Furthermore, LVHIIT reduced the systolic blood pressure (RR =-4.01, 95% CI = -4.82 - -3.21, p<0.0001) and improved peak oxygen uptake (VO2peak) compared to the control group (RR= 5.45; 95% CI = 1.38 - 9.52, p =0.009).

Conclusion

After a certain period of LVHIIT, glycaemic control, insulin resistance, body weight, lipid profile and cardiorespiratory outcomes were significantly improved in T2DM patients.