The Impact of Burst Exercise on Cardiometabolic Status of Patients Newly Diagnosed With Type 2 Diabetes

Physical exercise as treatment for adults with type 2 diabetes: a rapid review

Background

Type 2 diabetes mellitus (T2DM) is a leading cause of disability-adjusted life years (DALY). Physical exercise is an effective non-pharmacological intervention to promote glycaemic control in T2DM. However, the optimal exercise parameters for glycemic control in individuals with T2DM remain unclear.

Objective

This study aimed to analyze the relationship between physical training variables - frequency, intensity, type, duration, volume, and progression - and glycemic control in individuals with T2DM.

Methods

A rapid systematic literature review was conducted on PubMed and LILACS databases. The PICOT strategy was employed to define the inclusion criteria. Eligible studies had to assess the impact of exercise parameters (frequency, intensity, type, duration, volume, and progression) on glycemic control indicators, primarily glycosylated hemoglobin (HbA1c). Randomized and non-randomized clinical trials were included in the review. The methodological quality of each study was assessed using the PEDro scale (PROSPERO - CRD 42021262614).

Results

Out of 1188 papers initially identified, 18 reports met the inclusion criteria and were included in the analysis. A total of 1,228 participants with T2DM (1086 in exercise groups) were included in the selected studies. Among these studies, 16 (88.9%) were RCTs and 2 (11.1%) were nRCTs. The age of participants ranged from 43.1 and 68.9 years, and the average intervention duration was 16.8 weeks. Data on adherence to the intervention, adverse events, detailed intervention protocol, and its impacts on glycaemic control, lipid profile, blood pressure, anthropometric measures, medication, body composition, and physical fitness are reported.

Conclusion

The evidence supports the safety and effectiveness of physical exercises as non-pharmacological interventions for glycemic control. Aerobic, resistance and combined training interventions were associated with reductions in HbA1c and fasting glucose. The diversity of the physical exercise intervention protocols investigated in the studies included in this review is an important limitation to generalizing evidence-based practice. The call for action is mandatory to implement large-scale education programs on the prevention of diabetes and public health policies aimed to include well-planned and supervised exercise programs as an essential part of the primary prevention of type 2 diabetes.

Systematic Review Registration

PROSPERO, identifier (CRD42021262614).

High-Intensity Interval Training in Older Adults: a Scoping Review

High-intensity interval training (HIIT) is an increasingly popular form of aerobic exercise which includes bouts of high-intensity exercise interspersed with periods of rest. The health benefits, risks, and optimal design of HIIT are still unclear. Further, most research on HIIT has been done in young and middle-aged adults, and as such, the tolerability and effects in senior populations are less well-known. The purpose of this scoping review was to characterize HIIT research that has been done in older adults including protocols, feasibility, and safety and to identify gaps in the current knowledge. Five databases were searched with variations of the terms, "high-intensity interval training" and "older adults" for experimental or quasi-experimental studies published in or after 2009. Studies were included if they had a treatment group with a mean age of 65 years or older who did HIIT, exclusively. Of 4644 papers identified, 69 met the inclusion criteria. The average duration of training was 7.9 (7.0) weeks (mean [SD]) and protocols ranged widely. The average sample size was 47.0 (65.2) subjects (mean [SD]). Healthy populations were the most studied group (n = 30), followed by subjects with cardiovascular (n = 12) or cardiac disease (n = 9), metabolic dysfunction (n = 8), and others (n = 10). The most common primary outcomes included changes in cardiorespiratory fitness (such as VO2peak) as well as feasibility and safety of the protocols as measured by the number of participant dropouts, adverse events, and compliance rate. HIIT protocols were diverse but were generally well-tolerated and may confer many health advantages to older adults. Larger studies and more research in clinical populations most representative of older adults are needed to further evaluate the clinical effects of HIIT in these groups.

Acute glycaemic management before, during and after exercise for cardiac rehabilitation participants with diabetes mellitus: a joint statement of the British and Canadian Associations of Cardiovascular Prevention and Rehabilitation, the International Council for Cardiovascular Prevention and Rehabilitation and the British Association of Sport and Exercise Sciences

Type 1 (T1) and type 2 (T2) diabetes mellitus (DM) are significant precursors and comorbidities to cardiovascular disease and prevalence of both types is still rising globally. Currently,~25% of participants (and rising) attending cardiac rehabilitation in Europe, North America and Australia have been reported to have DM (>90% have T2DM). While there is some debate over whether improving glycaemic control in those with heart disease can independently improve future cardiovascular health-related outcomes, for the individual patient whose blood glucose is well controlled, it can aid the exercise programme in being more efficacious. Good glycaemic management not only helps to mitigate the risk of acute glycaemic events during exercising, it also aids in achieving the requisite physiological and psycho-social aims of the exercise component of cardiac rehabilitation (CR). These benefits are strongly associated with effective behaviour change, including increased enjoyment, adherence and self-efficacy. It is known that CR participants with DM have lower uptake and adherence rates compared with those without DM. This expert statement provides CR practitioners with nine recommendations aimed to aid in the participant's improved blood glucose control before, during and after exercise so as to prevent the risk of glycaemic events that could mitigate their beneficial participation.

HIIT is not superior to MICT in altering blood lipids: a systematic review and meta-analysis

Objective

To compare the effects of moderate intensity continuous training (MICT) and high intensity interval training (HIIT) on adult lipid profiles; to identify training or participant characteristics that may determine exercise-induced change in total cholesterol (TC), triglycerides (TRG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C).

Design

Systematic review and meta-analysis.

Data sources

English language searches of several databases were conducted from inception until September 2019.

Eligibility criteria for excluding studies

Inclusion: (1) published randomised controlled human trials with group population n≥5; (2) intervention duration ≥4 weeks; (3) comparing HIIT with MICT; and (4) reporting pre–post intervention lipid measurements. Exclusion: subjects with chronic disease, <18 years, pregnant/lactating, in elite athletic training; and studies with a dietary or pharmaceutical intervention component.

Results

Twenty-nine data sets (mmol/L) of 823 participants were pooled and analysed. Neither HIIT nor MICT was better in decreasing TC (0.10 (−0.06 to 0.19), p=0.12, I²=0%), TRG (−0.05 (−0.11 to 0.01), p=0.10, I²=0%), LDL-C (0.05 (−0.06 to 0.17), p=0.37, I²=0%), or TC/HDL-C (−0.03 (−0.36 to 0.29), p=0.85, I²=0%). HIIT significantly raised HDL-C (0.07 (0.04 to 0.11), p<0.0001, I²=0%) compared with MICT.

Conclusion

Neither HIIT nor MICT is superior for altering TC, TRG, or LDL-C, or TC-HDL-C ratio. Compared with MICT, HIIT appeared to significantly improve HDL-C. Clinicians may prescribe either protocol to encourage participation in exercise and reduce cardiovascular risk. To raise HDL-C, HIIT may result in a larger effect size compared with MICT.

PROSPERO registration number

CRD42019136722.

Effect of Exercise on Risk Factors of Diabetic Foot Ulcers: A Systematic Review and Meta-Analysis

The objectives of this study were to examine the effectiveness of different types of exercise on risk factors of diabetic foot ulcers, including glycated hemoglobin, peripheral arterial disease, and diabetic peripheral neuropathy, in people with type 2 diabetes mellitus. PubMed, Web of Science, Cochrane Library, Scopus, and CINAHL were searched from inception to January 2018 for relevant articles. Eligible studies were randomized controlled trials that examined effects of exercise on the selected risk factors. Twenty randomized controlled trials with 1357 participants were included in the meta-analyses. The differences in postintervention values of glycated hemoglobin and ankle brachial index between exercise and control groups were synthesized, yielding mean differences of -0.45% (P < 0.00001) and 0.03 (P = 0.002), respectively; the differences in within-group changes in glycated hemoglobin were synthesized, yielding mean differences of -0.19% (P = 0.1), -0.25% (P = 0.0006), and -0.64% (P = 0.006) for aerobic versus resistance, combined versus aerobic, and combined versus resistance exercise, respectively. Exercise has a significant effect on reducing glycated hemoglobin, whereas combined exercise is more effective compared with aerobic or resistance exercise alone. Exercise also improves ankle brachial index. However, evidence regarding the association between exercise and peripheral neuropathy and risks of diabetic foot ulcers in people with type 2 diabetes mellitus remains insufficient.

Exercise Intensities as Factors of Metabolic Outcomes in Type 2 Diabetes: A Systematic Review

Exercise is effective to prevent and treat type 2 diabetes, although currently underutilized. This review analyzes the metabolic response to exercise performance at various intensities in individuals with type 2 diabetes. These findings provide insight into the development of safe and efficacious exercise prescriptions and education. We conducted a systemic review of the literature to examine the association of various exercise protocols with metabolic outcomes in type 2 diabetes. Between 1984 and 2018, 29 studies were categorized per exercise mode and intensity levels according to the American College of Sports Medicine standards. The most consistent improvement was found in HbA1c following moderate- to high-intensity exercise—post-exercise fasting glucose improved to a lesser extent. Low-intensity exercise improved HOMA-IR (homeostasis model assessment for insulin resistance) levels. Glucose and HbA1c improved most following interval compared with continuous exercise, irrespective of intensity. A comparison of high-intensity exercise with moderate-intensity exercise demonstrated few differences in HbA1c, fasting glucose, fasting insulin, and HOMA-IR. Irrespective of exercise intensity, HbA1c improvements were observed, suggesting a delayed progression to diabetes-related complications. Initial low-intensity exercise, with increased quantities when feasible, will contribute to metabolic improvements. The variability in methodology and measurement contributed to inconsistent outcomes; additional research with larger samples sizes is warranted.

Effects of Exercise to Improve Cardiovascular Health

Obesity is a complex disease that affects whole body metabolism and is associated with an increased risk of cardiovascular disease (CVD) and Type 2 diabetes (T2D). Physical exercise results in numerous health benefits and is an important tool to combat obesity and its co-morbidities, including cardiovascular disease. Exercise prevents both the onset and development of cardiovascular disease and is an important therapeutic tool to improve outcomes for patients with cardiovascular disease. Some benefits of exercise include enhanced mitochondrial function, restoration and improvement of vasculature, and the release of myokines from skeletal muscle that preserve or augment cardiovascular function. In this review we will discuss the mechanisms through which exercise promotes cardiovascular health.

Glycemic Threshold as an Alternative Method to Identify the Anaerobic Threshold in Patients With Type 2 Diabetes

Purpose: To analyze the agreement between the velocity, heart rate, and oxygen uptake values corresponding to second ventilatory threshold and glycemic threshold in patients with type 2 diabetes. Methods: Twenty-four untrained patients (55.1 ± 8.9 years) were evaluated. Three different parameters of training intensity corresponding to anaerobic threshold, one mechanical (velocity) and two physiological (heart rate and oxygen uptake) parameters, were identified by a classical method (second ventilatory threshold) and by an alternative method (glycemic threshold). To determine the threshold values, patients performed an incremental treadmill test, with an initial velocity of 3 km.h-1 for 3 min, that was then increased by 1 km.h-1 every 2 min. Comparisons between mean values and the degree of agreement between second ventilatory threshold and glycemic threshold were analyzed using the paired t-test and Bland-Altman test, respectively. Results: All patients performed the tests appropriately, and no adverse effects were recorded. Patients demonstrated similar mean velocity (p = 0.25), heart rate (p = 0.97) and oxygen uptake (p = 0.71) between the ventilatory threshold (6.4 ± 0.6 km.h-1, 130.1 ± 18.7 bpm, 15.2 ± 3.5 ml.kg.min-1) and the glycemic threshold (6.2 ± 0.9 km.h-1, 130.2 ± 12.8 bpm, 15.0 ± 3.8 ml.kg.min-1). Conclusion: The present study indicates an agreement between the glycemic and second ventilatory methods in determination of the anaerobic threshold of patients with type 2 diabetes; and thus, either method may be used for these patients.