Table 4 Overview of existing reviews
First author | Title | Year of publication | Type of exercise | Information source | Primary outcome assessed | No. of trials | No. of patients | Published protocol | Assessment of adverse event | Assessment of risk of bias | Conclusion |
|---|---|---|---|---|---|---|---|---|---|---|---|
Reviews assessing effectiveness of exercise in people with cardiovascular disease | |||||||||||
 Powell [33] | Is exercise-based cardiac rehabilitation effective? A systematic review and meta-analysis to re-examine the evidence | 2018 | Exercise vs usual care (Type of exercise not specified) | Pubmed/Rehabilitation Medicine | Total mortality, cardiovascular mortality, hospital re-admission | 22 | 4834 | No | No | Yes (Risk of bias tool) | No reduction in total mortality and cardiovascular mortality |
 Anderson L [34] | Exercise based cardiac rehabilitation for coronary heart disease | 2016 | Exercise vs usual care (Type of exercise not specified) | Cochrane/Cochrane Database Syst Rev | Total mortality, cardiovascular mortality | 63 | 14486 | Yes | No | Yes (Risk of bias tool) | Reduction in total mortality but not cardiovascular mortality |
 Taylor RS [35] | Exercise-based rehabilitation for patients with coronary heart disease: systematic review and meta-analysis of randomized controlled trial | 2004 | Exercise vs usual care (Type of exercise not specified) | Pubmed/Am J Med | Total mortality, cardiovascular mortality | 48 | 8940 | No | No | Yes (Jadad Scale) | Reduction in both total mortality and cardiovascular mortality |
 Gloria Y. Yeh [36] | Tai Chi Exercise for Patients with Cardiovascular Conditions and Risk Factors: A Systematic Review | 2010 | Tai Chi | Pubmed/J Cardiopulm Rehabil Prev | Blood pressure, exercise capacity | 14 (9 RCTs) | - | No | No | Yes (Quality Grading) | May have some benefit but inconclusive |
 Rees K [37] | Exercise based rehabilitation for heart failure (Review) | 2004 | Exercise vs usual care (Type of exercise not specified) | Cochrane/Cochrane Database Syst Rev | Total mortality, morbidity, hospital re-admission, physical capacity, quality of life | 29 | 1126 | Yes | Yes | Yes (Jadad Scale) | Exercise improved people’s fitness and quality of life, without causing harm but the trials included were small who are unrepresentative of the total population of patients with heart failure |
 Long L et al. [38] | Exercise-based cardiac rehabilitation for adults with stable angina | 2018 | Exercise vs usual care (Type of exercise not specified) | Cochrane/Cochrane Database Syst Rev | All-cause mortality, morbidity health-related quality of life (e.g. (SF-36), (EQ-5D), exercise capacity (e.g VO2peak, 6-min walk test), cardiovascular-related hospital admissions | 8 | 581 | Yes | Yes | Yes (Risk of bias tool) | Small trials, potential risk of bias and concerns about imprecision and lack of applicability, the effects of exercise-based CR compared with control on mortality, morbidity, cardiovascular hospital admissions, adverse events, return to work and health-related quality of life in people with stable angina was uncertain |
 Saunders DL et al. [39] | Physical fitness training for stroke patients | 2016 | Cardiorespiratory training, resistance training, mixed training | Cochrane/Cochrane Database Syst Rev | Case fatality, death or dependence (Barthel Index score, Rankin score), disability (e.g. Functional Independence Measure, Stroke Impact scale etc.) | 45 | 2188 | Yes | Yes | Yes (Risk of bias tool) | Cardiorespiratory fitness training can improve exercise ability and walking after stroke. Further well-designed randomised trials are needed to determine the optimal exercise prescription and identify long-term benefits |
 Ismail et al. [40] | Clinical Outcomes and Cardiovascular Responses to Different Exercise Training Intensities in Patients With Heart Failure A Systematic Review and Meta-Analysis | 2013 | Aerobic exercise training | JACC/Heart Fail | Peak VO2 (baseline and after exercise), training frequency, intensity, duration per session, length of program, participant completion rates, mortality, adverse medical events and hospitalisations | 74 | 5877 | No | Yes | Yes (PEDrO Scale) | Magnitude of gain in cardiorespiratory fitness is greater with increasing exercise intensity. High and vigorous exercise intensities did not appear to increase the risk for study withdrawal, death, adverse events and hospitalisation |
 Davies EJ et al. [41] | Exercise training for systolic heart failure: Cochrane systematic review and meta-analysis | 2010 | Exercise versus usual care (Type of exercise not specified) | Pubmed/European Journal of Heart Failure | All-cause mortality, hospital admission/re-admission rates, HRQoL assessed by a validated outcome measure (e.g. MLWHF questionnaire or Short Form 36 (SF-36)) and cost-effectiveness | 19 | 3647 | No | No | Yes (Risk of bias tool) | No significant difference between exercise and control in short-term (≤ 12 months) or longer term all-cause mortality or overall hospital admissions. |
Reviews assessing effectiveness of exercise in people with hypertension | |||||||||||
 Whelton SP et al. [42] | Effect of Aerobic Exercise on Blood Pressure: A Meta-Analysis of Randomized, Controlled Trials | 2002 | Aerobic exercise | Pubmed/Annals of Internal Medicine | Blood pressure | 54 | 2419 | No | No | No | Aerobic exercise reduces blood pressure in both hypertensive and normotensive persons. |
 MacDonald HV et al. [43] | Dynamic Resistance Training as Stand-Alone Antihypertensive Lifestyle Therapy: A Meta-Analysis | 2016 | Dynamic resistance training | Pubmed/J Am Heart Assoc | Blood pressure | 64 | 2344 | No | No | No | For non-white adult samples with hypertension, dynamic RT may elicit BP reductions that are comparable with or greater than those reportedly achieved with AE training |
 Cornelissen et al. [44] | Exercise Training for Blood Pressure: A Systematic Review and Meta-analysis | 2013 | Endurance, Resistance, Isometric resistance, Combined exercise | Pubmed/J Am Heart Assoc. | Blood pressure | 93 | 5223 | No | No | No | Endurance, dynamic resistance and isometric resistance training lower SBP and DBP, whereas combined training lowers only DBP. |
 Cramer H et al. [45] | A Systematic Review and Meta-Analysis of Yoga for Hypertension | 2014 | Yoga | Pubmed/Am J Hypertens | Blood pressure | 7 | 452 | No | No | Yes (Risk of bias tool) | Larger studies are required to confirm the emerging but low-quality evidence that yoga may be a useful adjunct intervention in the management of hypertension |
 Chu P et al. [46] | The effectiveness of yoga in modifying risk factors for cardiovascular disease and metabolic syndrome: A systematic review and meta-analysis of randomized controlled trials | 2016 | Yoga | Pubmed/Eur J Prev Cardiol | BMI, systolic blood pressure, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol | 37 | - | No | No | Yes (Risk of bias tool) | Promising evidence of yoga on improving cardio-metabolic health. Findings are limited by small trial sample sizes, heterogeneity and moderate quality of RCTs. |
 Hagins M et al. [47] | Effectiveness of Yoga for Hypertension: Systematic Review and Meta-Analysis | 2013 | Yoga | Pubmed/Evid Based Complement Alternat Med | Systolic and diastolic blood pressure | 17 | - | No | No | Yes (Risk of bias tool) | Yoga can be preliminarily recommended as an effective intervention for reducing blood pressure. Additional rigorous controlled trials are warranted to further investigate the potential benefits of yoga. |
Reviews assessing effectiveness of exercise in type 2 diabetes mellitus | |||||||||||
 Thomas D [48] | Exercise for type 2 diabetes mellitus (Review) | 2009 | Aerobic, fitness or progressive resistance training exercise | Cochrane/Cochrane Database Syst Rev | HbA1c | 14 | 377 | Yes | Yes | Yes (Risk of bias tool) | Reduced HbA1c even without reducing weight. No trials included reported mortality. No adverse event was reported. |
 Hayashino Y [49] | Effects of supervised exercise on lipid profiles and blood pressure control in people with type 2 diabetes mellitus: A meta-analysis of randomized controlled trials | 2012 | Aerobic, resistance or combined | Pubmed/Diabetes Research and Clinical Practice | Blood pressure and lipid profile | 42 | - | No | No | Yes (Verhagen et. al's tool) | Supervised exercise is effective in improving blood pressure and lipid profile. |
 Grace A et al. [50] | Clinical outcomes and glycaemic responses to different aerobic exercise training intensities in type 2 diabetes: a systematic review and meta-analysis | 2017 | Aerobic exercise | Pubmed | % change in HbA1c | 27 | 1372 | No | No | Yes (TESTEX) | Improvement in HbA1c. Higher intensity of exercise gives bigger benefit. |
 Snowling NJ et al. [51] | Effects of Different Modes of Exercise Training on Glucose Control and Risk Factors for Complications in Type 2 Diabetic Patients. A meta-analysis | 2006 | Aerobic Resistance Combined | Pubmed/Diabetes care | Glucose control HbA1c | 27 | - | No | No | No | All forms of exercise training produce small benefits in the main measure of glucose control: HbA1c |
 Liu Y et al. [52] | Resistance Exercise Intensity is Correlated with Attenuation of HbA1c and Insulin in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis | 2019 | Resistance | Pubmed/Int J Environ Res Public Health | HbA1c Insulin | 24 | 962 | No | No | Yes (Risk of bias tool) | High-intensity RE has greater beneficial effects than low-to-moderate-intensity in attenuation of HbA1c and insulin in T2D patients. |
 Schwingshackl L et al. [25] | Impact of different training modalities on glycaemic control and blood lipids in patients with type 2 diabetes: a systematic review and network meta-analysis | 2014 | Aerobic, Resistance, Combined | Pubmed/Diabetologia | HbA1c | 14 | 915 | No | No | Yes (Risk of bias tool) | Combined interventions resulted in significantly more pronounced improvements in glycaemic control |
 Innes KE et al. [53] | Yoga for Adults with Type 2 Diabetes: A Systematic Review of Controlled Trials | 2015 | Yoga | Pubmed/Journal of Diabetes Research | Glycaemia and insulin resistance, lipid profile, body weight and composition, blood pressure | 33 (12 RCTs) | . | No | No | Yes (PEDrO Scale) | Methodological limitation of existing evidence to report beneficial effect of yoga |
 Ciu J et al. [54] | Effects of yoga in adults with type 2 diabetes mellitus: A meta-analysis | 2017 | Yoga | Pubmed/Journal of Diabetes Investigation | Fasting blood glucose | 12 | 864 | No | No | Yes (Jadad Scale) | Methodological limitation and possible heterogeneity cannot confirm the beneficence of yoga, further studies needed. |
 Chao et al. [55] | The Effects of Tai Chi on Type 2 Diabetes Mellitus: A Meta-Analysis | 2018 | Tai Chi | Pubmed/Journal of Diabetes Research | Fasting blood glucose | 14 | 798 | No | No | Yes (Jadad Scale) | Tai chi can effectively affect the management of blood glucose and HbA1c in type-2 DM patients |
 Xia TW et al. [56] | Different training durations and styles of tai chi for glucose control in patients with type 2 diabetes: a systematic review and meta-analysis of controlled trials | 2019 | Tai Chi | Pubmed/BMC Complementary and Alternative Medicine | HbA1c and fasting blood glucose | 17 | - | No | 2 trials reported no adverse event Rest did not report | Yes (Risk of bias tool) | Tai Chi seems to be effective in treating type 2 diabetes. Different training durations and styles result in variable effectiveness |
 Lee MS et al. [57] | Tai Chi for Management of Type 2 Diabetes Mellitus: A Systematic Review | 2011 | Tai Chi | Pubmed/Chin J Integr Meed | HbA1c and fasting blood glucose, quality of life | 10 | - | No | No | No | Exiting evidence does not suggest Tai chi is effective. There are few high-quality trials on which to make definitive judgements. |