|Year : 2021 | Volume
| Issue : 1 | Page : 17-30
Effects of structured Aerobic Exercise on selected clinical profiles of patients with type 2 diabetes mellitus: A systematic review with meta-analysis
Nmachukwu Ifeoma Ekechukwu1, Stella Udumma Anwara2, Ukamaka Gloria Mgbeojedo3, Olive U Chijioke4, Okechukwu Steven Onwukwe5, Uchechukwu Anthonia Ezugwu3, Echezona Nelson Dominic Ekechukwu6, Ijeoma L Okoronkwo7
1 LANCET Physiotherapy, Wellness and Research Centre, Enugu, Nigeria
2 Department of Physiotherapy, University of Abuja Teaching Hospital, Abuja, Nigeria
3 Department of Medical Rehabilitation, Faculty of Health Sciences and Technology, College of Medicine, University of Nigeria, Nsukka, Nigeria
4 Department of Health Administration and Management, Faculty of Health Sciences and Technology, College of Medicine, University of Nigeria, Nsukka, Nigeria
5 Department of Medical Laboratory Sciences, College of Medicine, Faculty of Health Sciences and Technology, University of Nigeria, Enugu Campus, Enugu, Nigeria
6 LANCET Physiotherapy, Wellness and Research Centre, Enugu, Nigeria; Department of Medical Rehabilitation, Faculty of Health Sciences and Technology, College of Medicine, University of Nigeria, Nsukka, Nigeria
7 Department of Health Administration and Management, Faculty of Health Sciences and Technology, College of Medicine, University of Nigeria, Nsukka, Nigeria; Department of Nursing Sciences, Faculty of Health Sciences and Technology, College of Medicine, University of Nigeria, Nigeria
|Date of Submission||01-May-2020|
|Date of Decision||24-Jul-2020|
|Date of Acceptance||07-Sep-2020|
|Date of Web Publication||21-Oct-2020|
Echezona Nelson Dominic Ekechukwu
Department of Medical Rehabilitation, Faculty of Health Sciences & Technology, College of Medicine, University of Nigeria, Nigeria; LANCET Physiotherapy, Wellness & Research, Enugu.
Source of Support: None, Conflict of Interest: None
This review sought to examine the pooled effects of Aerobic Exercise (AeroEx) on the glycemic, lipid, cardiovascular, and anthropometric profiles as well as the quality of life (QoL) of patients with type 2 diabetes mellitus (T2DM). Major electronic databases were searched systematically to identify randomized controlled studies that examined the effects of AeroEx in with T2DM. The methodological quality of each study was evaluated using the PEDro scale. Meta-analysis was performed on a given outcome when appropriate. Twelve trials fulfilled the selection criteria. Most of the studies prescribed AeroEx using treadmill (41.7%) or cycle ergometer (58.3%), at a moderate training intensity (58.3%) for ≥3 days/week (100%), 41–60 min/day (66.7%) and for ≥16 weeks (41.6%). Meta-analysis showed a significant effect on glycemic profiles (glycated hemoglobin [SMD = –2.06; CI = –2.34, –1.79], fasting blood glucose [SMD = –1.20; CI = –1.45, –0.95]), lipid profiles (total cholesterol [SMD = –1.35; CI = –1.58, –1.12], low-density lipoprotein [LDL] [SMD = –0.67; CI = –1.22, –0.12]), cardiovascular profiles (maximum oxygen consumption [SMD = 0.58; CI = 0.20, 0.96], diastolic blood pressure [SMD = –0.40; CI = –0.60, –0.21]), anthropometric profiles (percentage body fat [SMD = –1.09; CI = –1.37, –0.82], BMI [SMD = –1.81; CI = –2.16, –0.87]) and QoL (SMD = 2.23; CI = 1.56, 2.90) in favor of AeroEx. In conclusion, chronic AeroEx with moderate intensity induces glycemic control, regulates the lipid profiles, promotes cardiovascular health, and improves overall QoL of patients with T2DM.
Keywords: Aerobic Exercise, clinical profiles, quality of life, systematic review, type-2 diabetes mellitus
|How to cite this article:|
Ekechukwu NI, Anwara SU, Mgbeojedo UG, Chijioke OU, Onwukwe OS, Ezugwu UA, Ekechukwu EN, Okoronkwo IL. Effects of structured Aerobic Exercise on selected clinical profiles of patients with type 2 diabetes mellitus: A systematic review with meta-analysis. Int J Med Health Dev 2021;26:17-30
|How to cite this URL:|
Ekechukwu NI, Anwara SU, Mgbeojedo UG, Chijioke OU, Onwukwe OS, Ezugwu UA, Ekechukwu EN, Okoronkwo IL. Effects of structured Aerobic Exercise on selected clinical profiles of patients with type 2 diabetes mellitus: A systematic review with meta-analysis. Int J Med Health Dev [serial online] 2021 [cited 2021 Jan 28];26:17-30. Available from: https://www.ijmhdev.com/text.asp?2021/26/1/17/298779
| Introduction|| |
Diabetes mellitus is a general term for the heterogeneous disturbances of metabolism for which the main finding is chronic hyperglycemia caused by impaired insulin secretion and/or impaired insulin action. Type 2 diabetes mellitus (T2DM) is one of the fastest-growing noncommunicable diseases worldwide. The number of people with T2DM (confirmed cases by undertaking diabetes tests) has risen from 108 million in 1980 to 422 million in 2014, while its global prevalence among adults over 18 years of age has risen from 4.7% in 1980 to 8.5% in 2014. The World Health Organization's recommendations for the prevention and management of T2DM include maintaining a healthy weight, consuming a healthy diet, and participation in exercise. Most T2DM prevention programs,,,, have recommended Aerobic Exercise with strong evidence supporting this approach. Structured aerobic exercise can help people with T2DM achieve a variety of goals, including increased cardiorespiratory fitness, increased vigor, improved glycemic control, decreased insulin resistance, improved lipid profile, blood pressure reduction, and maintenance of weight loss.
Most systematic reviews and meta-analysis,,, on the effects of aerobic exercise on selected health indices of patients with T2DM appear to have focused on glycemic control with little or no emphasis on other health indices like their quality of life (QoL) and anthropometric indices. The objective of this systematic review was to examine the pooled effects of aerobic exercises on the glycemic, lipid, cardiorespiratory and anthropometric profiles as well as the QoL and wound size of patients with T2DM. We also aimed to develop evidence-based exercise prescription recommendations based on these analyses. We therefore hypothesized that the systematic review of the literature would reveal compelling support for the effectiveness of aerobic exercise in patients with T2DM, such that detailed evidence-based exercise prescription recommendations could be derived.
| Materials and Methods|| |
The PICO method was used to define the four major components of the systematic review question: P (patient) = patients with T2DM; I (intervention) = exercise programs that include a substantial aerobic exercise component, with aerobic exercise being defined as ‘a structured exercise program that involves the use of large muscle groups for extended periods of time in activities that are rhythmic in nature, including but not limited to walking, stepping, running, swimming, cycling and rowing; C (comparison) = no intervention or other activities not designed to improve aerobic fitness; and O (outcome) = glycemic, lipid, cardiovascular and athropometric profiles and other health indicators such as QoL and wound size.
The eligibility criteria for article selection were formulated on the basis of the research question. Only randomized controlled trials (RCTs) that investigated the effects of aerobic exercise in patients with T2DM; that the aerobic training protocol was clearly described (e.g., mode, frequency, intensity, and time), and published in English were included. However, study reports published in books, doctoral dissertations, or reports published in conference proceedings were excluded. The primary outcomes of interest were glycemic profiles (glycated hemoglobin and fasting blood glucose [FBG]), total cholesterol, maximum oxygen consumption (VO2max), and percentage body fat and wound size. In addition, other indicators of general health status, particularly those relevant to other lipid (triglycerides [TGs], high-density lipoprotein [HDL], and LDL), cardiorespiratory (systolic and diastolic blood pressures, pulse rate, and respiratory rate), and anthropometric (body weight, body mass index, waist circumference and waist-hip ratio) profiles as well as QoL were also of interest and considered as secondary outcomes in this systematic review.
The following electronic databases were searched online by a research team member: Cochrane Library, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Science Direct, PubMed, and Physiotherapy Evidence Database (PEDro). Google search and a hand search of the reference list of existing articles were also conducted to find papers that did not appear in the main databases. The titles and abstracts of the articles generated by the search strategy were first screened to eliminate irrelevant articles. The articles that met the inclusion criteria after title/abstract screening had their full texts downloaded and reviewed to determine their final eligibility.
The PEDro score of each selected study, which is an indicator of the methodological quality (9–10 = excellent; 6–8 = good; 4–5 = fair; <4 = poor), was identified by searching the PEDro website [Table 1]. Based on the PEDro assessment and sample size used, the level of evidence was assigned to each study. High-quality RCTs (rated as good or excellent by PEDro and sample size >50) were considered level 1 evidence, whereas lower-quality RCTs were considered level 2 evidence (rated as fair or poor by PEDro, or sample size ≤50). The article selection and data extraction were performed by two research team members independently. The results were then confirmed by the principal investigator. Meta-analysis was conducted when appropriate to estimate the pooled treatment effect using Review Manager (version 5.1, the Nordic Cochrane Center, Copenhagen, Denmark). Meta-analysis was performed only if three or more studies measured the same outcome of interest. The change scores (postintervention score–preintervention score) for each of the experimental and control groups were used for the meta-analysis.
|Table 1: Summary of methodological quality of studies and diabetes characteristic|
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| Results|| |
A PRISMA flow diagram of the literature search and selection is presented in [Figure 1]. From 4547 potentially relevant studies retrieved from our main and additional manual search, we identified 12 trials that fulfilled the inclusion criteria. Considering both the PEDro ratings and sample size used, seven studies provided level 1 evidence whereas others were considered as level 2 studies. The methodological quality of the included trials ranged from fair to good, with an average PEDro score of 7.8. Eleven trials were methodologically good quality trials with scores ≥ 6, seven trials had a sample size ≥ 50 as shown in [Table 1].
In most of the selected studies aerobic exercise was performed using treadmill (41.7%) or cycle ergometer (58.3%), at a moderate training intensity of 61%–76% HRmax (58.3%) for 3–5 days per week (100%), 41–60 min per day (66.7%) and for ≥16 weeks (41.6%) as shown in [Table 2]. Of the 18 outcome variables measured, four (waist–hip ratio, respiratory rate, pulse rate, and wound size) were not included in the meta-analysis because they were assessed in less than three studies. One of these outcomes (wound size) is a primary outcome while the rest are secondary outcomes. Of the remaining outcomes measured, glycated hemoglobin (HbA1c) and FBGwere the most frequently measured outcomes (9 and 10 studies, respectively) among the studies involved in the meta-analysis.
| Effects of Aerobic Exercise on the Primary Outcomes|| |
The meta-analysis incorporated nine trials,,,,,,,, that assessed glycated hemoglobin resulting in a total of 611 participants. There was a significant pooled effect (reduction) on HbA1c in favor of the aerobic exercise group (SMD = –2.06; CI = –2.34, –1.79) as shown in [Figure 2]A. When all level 2 studies were extruded, only four studies,,, with level 1 evidence (contributing 483 participants) were left. The meta-analysis of these studies still revealed that aerobic exercise had a significant pooled effect in decreasing HbA1c (SMD = –1.93; CI = –2.23, –1.63) as shown in [Figure 2]B.
|Figure 2: A: Forest plot for glycated hemoglobin (HbA1c). B: Forest plot for glycated hemoglobin (HbA1c) using only Level 1 trials|
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Six trials,,,,, measured total cholesterol that gave a total of 724 participants. A study had a significant effect in reducing TC that favored the control group while the rest of the trials had significant effects in favor of the aerobic exercise group. Summarily, the pooled decreasing effect (SMD = –1.35; CI = –1.58, –1.12) was in favor of aerobic exercise as shown in [Figure 3]A. Also, when the only level 2 study was extruded (leaving a total of 686 participants involved in the analysis), the pooled decreasing effect was still in favor of the aerobic exercise group (SMD = –1.28; CI = –1.51, –1.05) as shown in [Figure 3]B.
|Figure 3: (A) Forest plot for total cholesterol (TC). (B) Forest plot for total cholesterol (TC) using only Level 1 trials|
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Fasting blood glucose
FBG was measured in 10 of the included trials,,,,,,,,, resulting in a total of 720 participants; seven of them had significant decreasing effects in favor of the aerobic exercise while three of the trials,, had no significant effect. However, the pooled decreasing effect on FBG (SMD = –1.20; CI = –1.45, –0.95) was significantly in favor of the aerobic exercise group as shown in [Figure 4]A. In the same vein, a significant decreasing effect in favor of aerobic exercise was also found in the analysis involving only level 1 studies with a total of 607 participants (SMD = –1.70; CI = –1.33, –0.80) as shown in [Figure 4]B.
|Figure 4: (A) Forest plot for fasting blood glucose (FBG). (B) Forest plot for fasting blood glucose (FBG) using only Level 1 trials|
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Maximum oxygen consumption (VO2max)
Four trials,,, with a total of 197 participants measured this primary outcome. One of the studies had a significant increasing effect in favor of the control group; another study had no significant effect, while the other two trials, had significant improving effects in favor of the aerobic exercise group. The pooled improving effect on VO2max (SMD = 0.58; CI = 0.20, 0.96) was significantly in favor of the aerobic exercise group as shown in [Figure 5]A. However, the analysis using the two trials, with level 1 evidence that gave a total of 140 participants showed no significant benefit (SMD = 0.06; CI = –0.40, –0.51) as shown in [Figure 5]B.
|Figure 5: (A) Forest plot for maximal oxygen consumption (VO2max). (B) Forest plot for maximal oxygen consumption (VO2max) using only Level 1 trials|
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Percentage body fat
Three trials, all with level 1 evidence,, that resulted in a total of 391 participants measured percentage body fat. One of the trials had a significant decreasing effect in favor of the aerobic exercise group; another study had a significant decreasing effect in favor of the control group, while the other trial showed no significant effect. However, the pooled effect showed a significant reduction of %BF (SMD = –1.09; CI = –1.37, –0.82) in favor of aerobic exercise as shown in [Figure 6].
| Effects of Aerobic Exercise on the Secondary Outcomes|| |
Systolic and diastolic blood pressures were measured in six trials,,,,, that gave a total of 597 participants for each of the outcomes. For the systolic blood pressure, three trials,, had significant decreasing effects in favor of the aerobic exercise group, a study had a significant decreasing effect in favor of the control group while two trials, showed no significant effect. The pooled effect (SMD = –0.19, CI = –0.40, 0.02) was however nonsignificant as shown in [Figure 7]. On the contrary, there was a significant decreasing pooled effect on diastolic blood pressure (SMD = –0.40; CI = –0.60, –0.21) in favor of the aerobic exercise group as shown in [Figure 8].
Four trials,,, with a total of 560 participants assessed the effect of aerobic exercise on HDL. Three of the trials,, had a nonsignificant increasing effect in favor of the aerobic exercise group while the fourth trial had a significant increasing effect on HDL. The pooled effect (SMD = 0.18; CI = –0.02, 0.37) in improving HDL for these four trials was in favor of the aerobic exercise group though nonsignificantly as shown in [Figure 9].
Four trials,,, with a total of 560 participants assessed the effect of aerobic exercise on LDL. Three of the trials,, had a significant decreasing effect in favor of the aerobic exercise group while a trial had a significant decreasing effect in favor of the control group. However, the overall decreasing effect (SMD = –0.67; CI = –1.22, –0.12) was significantly in favor of aerobic exercise as shown in [Figure 10].
Four out of the six trials (752 participants) that assessed TG,,, had significant decreasing effects in favor of the aerobic exercise group while the other two studies, showed no significant effect on TG. There was, however, a significant decreasing pooled effect on TG (SMD = –.1.15; CI = –1.43, –0.8) in favor of aerobic exercise as shown in [Figure 11].
Two of the three trials (352 participants) that assessed the effects of aerobic exercise on the body weight of patients with T2DM, reported a significant decreasing effect in favor of the aerobic exercise group while a trial showed a significant decreasing effect in favor of the control group. However, the pooled effect (SMD = –1.15; CI = –1.43, –0.87) was significantly in favor of aerobic exercise as shown in [Figure 12].
Body mass index
A total of seven studies,,,,,, with a total of 555 participants incorporated Body mass index as an outcome. Three of these trials,, had a significant decreasing effect in favor of the aerobic exercise group; two trials, had no significant effect while the other two trials, showed significant decreasing effects in favor of the control group. However, the pooled effect (SMD = –1.81; CI = –2.16, –0.87) was significantly in favor of aerobic exercise as shown in [Figure 13].
Waist circumference was measured as an outcome in three trials,, that resulted in 352 participants. Two of these trials, showed a significant decreasing effect in favor of aerobic exercise while the other study had a significant decreasing effect in favor of the control group. However, the pooled effect (SMD = –2.72; CI = –3.49, –1.94) was significantly in favor of aerobic exercise as shown in [Figure 14].
Quality of life
This outcome was assessed in three trials,, that gave a total of 72 participants. Two of the trials, had a significant increasing effect in favor of the aerobic exercise group while the other trial showed no significant effect on QOL. However, there was an increasing significant pooled effects on QoL (SMD = 2.23; CI = 1.56, 2.90) in favor of the aerobic exercise group as shown in [Figure 15].
| Discussion|| |
This study provides an updated review of the current evidence related to the use of aerobic exercise in influencing various health indicators in persons living with T2DM, and provides the foundation for developing an evidence-based exercise prescription for this population. Majority of the studies reviewed prescribed aerobic exercise using treadmill or cycle ergometer at moderate training intensity for 16 weeks and above, 3–5 days per week and 41–60 min per day. Treadmill and cycle ergometers are commonly found aerobic training devices in most labs/gymnasia possibly because structured aerobic exercise parameters such as time, intensity using heart rates, distance covered for estimating VO2max, calories burnt, etc., can be objectively assessed electronically using these modes as compared to other modes such as stair-climbing, brisk walking, yoga, etc. Also, these modes do not require large space when compared to modes such as walking and running utilized in 6-min walk tests and the 1.5 miles run tests, respectively. Therefore, structured aerobic exercise can be objectively prescribed for with T2DM using a threadmill and/or cycle ergometers.
Glycated hemoglobin’s are characteristically Ketoamines, formed through a two-step nonenzymatic pathway between hemoglobin and blood glucose. Blood glucose and hemoglobin are combined to form aldimine as a first step, which is a reversible form. In the second step, this labile aldimine is slowly converted to ketoamine form which is stable and irreversible. In individuals with poorly controlled diabetes, the quantities of these glycated hemoglobin’s are much higher than in healthy people. The HbA1c level is directly proportional to average blood glucose concentration over the previous 4 weeks to 3 months or the average lifespan of the erythrocyte. Higher amounts of HbA1c in diabetic patients, indicating poorer control of blood glucose levels, have been associated with diabetic complications such as cardiovascular disease, nephropathy, and retinopathy. Studies,,, have shown that HbA1c is an important indicator of glycemic control.
In this review, aerobic exercise was significantly effective in reducing HbA1c in patients with T2DM. Of the nine included studies that assessed HbA1c, only the study by Bello et al., had no significant effect in reducing HbA1c among their participants; although, the pooled effects of the nine studies was in favor of aerobic exercise (having a significant decreasing effects on HbA1c). Aerobic exercise improves glycemic control in type 2 diabetes through several mechanisms. During exercise, glucose uptake occurs in an exercise intensity/duration-dependent manner due to increased glucose delivery, glucose transport, and glucose metabolism., Also, post-exercise enhancement of insulin sensitivity is a contributory mechanism for explaining exercise-induced glycemic control. Other mechanisms include Redox homeostasis; exercise-induced oxidative stress, stress-activated protein kinase (SAPK) signaling, and mitogen-activated protein kinase (MAPK) signaling.
Of the six studies that incorporated total cholesterol in this meta-analysis, only one reported nonsignificant effect of aerobic exercise. However, the pooled effects of the six RCTs were significantly in favor of aerobic exercise. Therefore, one can substantially state that aerobic exercise plays a vital role in the control and management of the total cholesterol of patients with T2DM. The most commonly used measure of cholesterol is arguably total cholesterol, a measure that includes LDL cholesterol and HDL cholesterol. A reduction in total cholesterol is considered the gold standard in preventative cardiovascular medicine. This result highlights the importance aerobic exercise in reducing serum cholesterol levels among diabetic patients. While the mechanisms underlying the effect of aerobic exercise on the lipid profile are unclear, aerobic exercise appears to enhance the ability of skeletal muscles to utilize lipids, thus reducing plasma lipid levels. The mechanisms may also include increases in lecithin cholesterol acyltransferase (LCAT)—the enzyme responsible for ester transfer to HDL cholesterol, which has been found to increase following exercise training. Also, exercise-induced increase in lipoprotein lipase activity is another possible mechanism for regulating total cholesterol level in with T2DM using aerobic exercise.
Fasting blood glucose is the most common method for diagnosing diabetes and monitoring of blood glucose among diabetic patients because it is easy, convenient and less expensive. In this review, aerobic exercise had a significant pooled effect in decreasing the fasting blood glucose level of patients with T2DM. All the ten studies involved in this meta-analysis showed significant effect of aerobic exercise on the blood glucose level. Dysregulation of insulin activity (insulin resistance) and secretion (insulin deficiency) occurs in the development of diabetes. Aerobic exercise can circumvent dysfunctional insulin signaling and offers a potent nonpharmacological tool to augment glucose uptake in insulin-resistant muscle to normalize glycemic control through three mechanisms. First by increasing muscle capillarization that enhances glucose delivery. Secondly, by increasing Glucose Transporter type 4 (GLUT4) expression and translocation that enhance glucose transport. Finally by improving hexokinase and mitochondrial expression that enhances glucose metabolism.
The meta-analysis for VO2max showed that the pooled effect in increasing VO2max was in favor of the aerobic exercise group. This implies that aerobic exercise was significantly more effective in improving VO2max among with T2DM. It has been established that patients with T2DM even in the absence of clinically apparent cardiovascular complications have reduced cardiorespiratory endurance as measured by VO2max. Studies have fingered impairment in glycemic control, insulin resistance,, endothelial dysfunction, decreased blood flow, abnormal tissue hemoglobin oxygen saturation, diastolic dysfunction and decreased cardiac perfusion and more recently decreased muscle mitochondrial function to be partly responsible for the limitations in VO2max among patients with T2DM. These factors (impaired glycemic control, insulin resistance, endothelial dysfunction etc.) can be reversed with the use of aerobic exercise. Therefore these factors may explain the mechanism by which aerobic exercise improves VO2max among patients with T2DM. It is however pertinent that this result be interpreted with caution because similar meta-analysis with only high quality (level 1) studies, showed no significant effect. This may have been due to the small sample size drawn from the two RCTs (140 subjects). Therefore, more high quality randomized clinical trials assessing the effects of aerobic exercise on the VO2max of with T2DM is recommended.
The pooled effect in reducing percentage body fat was significantly in favor of aerobic exercise. The major complication of diabetes is cardiovascular disorders which can be further complicated by poor body composition indices such as percentage body fat. It has been demonstrated that loss of body fat leads to a reduction in insulin resistance. The Possible mechanisms underlying the aerobic exercise-induced fat loss effect include increased exercise and post-exercise fat oxidation, decreased post-exercise appetite and exercise-induced browning of adipose tissues. Skeletal muscle perilipin 3(PLIN3) and coatomer proteins (GBF1, ARF1, Sec23a, and ARFRP1) have been found to increase following aerobic exercise and these are associated with fat oxidation. Appetite hormones such as ghrelin, peptide tyrosine (PYY), and glucagon-like peptide 1 (GLP-1) are well known to play a critical role in nutrient signaling and subsequently in controlling appetite. Aerobic exercise has been found to modulate these hormones such that appetite becomes suppressed., Also, aerobic exercise-induced anorexia has also been explained via its increasing effect on interleukin 6.
There was a significant decrease in DBP and a nonsignificant decrease in SBP in favor of aerobic exercise. This implies that aerobic exercise is capable to reducing blood pressure especially the DSP among T2DM patients. This is achieved by strengthening the cardiac muscles, improving the efficiency of cardiac contractility and the resultant decrease in forceful ejection of blood from the heart. Aerobic exercise regulates blood pressure in patients with T2DM through its effects on the endothelia tissues and peripheral resistance, vessel elasticity as well as blood volume and cardiac output. In the same vein, aerobic exercise was effective in decreasing body weight, body mass index, and waist circumference. This was possibly achieved through the aerobic exercise-induced reduction in body fat as discussed above.
LDL and TG were significantly decreased with the pooled effects in favor of aerobic exercise while HDL was increased in favor of the aerobic exercise group though nonsignificantly. This implies that while aerobic exercise was effective in reducing LDL and TG, it may be effective in increasing HDL. Dyslipidemia is associated with T2DM and the most common patterns of dyslipidemia in diabetic patients are decreased HDL and elevated LDL and TGs. Aerobic exercise training increases the level of HDL especially the HDL-2 subfraction mainly by inhibiting HDL catabolism and/or in few cases increasing HDL synthesis. Also exercise-induced increase in lipoprotein lipase (LPL) results in hydrolysis of TG-rich lipoproteins and this partly explains the decrease in TG and LDL following exercise training.
Finally, the increase in QoL was significantly in favor of the aerobic exercise group. This implies that aerobic exercise was significantly effective in improving the overall QoL of persons with T2DM. T2DM has an adverse effect on QoL. Most patients suffer from a variety of long-term complications such as neuropathy, nephrolopathy, retinopathy, myocardial infarction, angina pectoris, stroke, and amputation. In addition, the trouble of taking oral antidiabetic agents several times a day, the fear of subcutaneous injection of insulin, and incidents of hypoglycemia might depress diabetic patients and further reduce health-related quality of life (HRQoL). Studies, have shown that the HRQoL of diabetic patients is worse than that of similarly aged nondiabetics. It is possible that the effects of aerobic exercise in inducing optimal cardiovascular health, glycemic control, regulation of lipid and anthropometric profiles of patients with T2DM may be responsible for the improved overall quality of health after chronic aerobic exercise.
| Conclusion|| |
Aerobic exercise using treadmill and/or cycle ergometer at moderate training intensity for at least 16 weeks, not less than 3 days per week and for about 40 min per day is capable of inducing glycemic control, regulate the lipid profiles, promote cardiovascular health, and improve overall QoL of patients with T2DM.
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Conflicts of interest
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11], [Figure 12], [Figure 13], [Figure 14], [Figure 15]
[Table 1], [Table 2]