Acessibilidade / Reportar erro

Effect of different physical training modalities on peak oxygen consumptions in post-acute myocardial infarction patients: systematic review and meta-analysis

Abstract

Physical training can increase peak oxygen uptake (VO2peak) in people who have suffered acute myocardial infarction (AMI). However, there is still a gap in the literature in relation to the effectiveness of different types of interventions. Therefore, the aim of the present study was to evaluate the effects of different physical training modalities on VO2peak in post-AMI patients. The following databases were used: PubMed (MEDLINE), Cochrane Library, Scopus, and Pedro. Studies that evaluated aerobic exercise, strength exercise, or combined exercise were included. Six studies met eligibility criteria. Aerobic exercise increased VO2peak by 6.07 ml.kg-1.min-1 when compared to the control group (CG) (p = 0.013). The comparison between combined exercise and control group detected a difference of 1.84 ml.kg-1.min-1, but this was not significant (p = 0.312). We therefore conclude that aerobic exercise is the only modality that is effective for increasing VO2peak compared to a control group.

Keywords:
physical exercise; acute myocardial infarction; cardiovascular rehabilitation; coronary artery disease; ischemic cardiopathy

Resumo

O treinamento físico é capaz de aumentar o consumo de oxigênio de pico em indivíduos que sofreram infarto agudo do miocárdio. No entanto, em relação à eficácia de diferentes tipos de intervenções ainda há uma lacuna na literatura. O objetivo do presente estudo foi avaliar os efeitos de diferentes modalidades de treinamento físico no consumo de oxigênio de pico de pacientes pós-infarto agudo do miocárdio. Foram utilizadas as seguintes bases de dados: PubMed (MEDLINE), Cochrane Library, Scopus e PEDro. Foram incluídos estudos que avaliassem exercícios aeróbicos, de força ou combinados. Seis estudos preencheram elegibilidade. O exercício aeróbico aumentou 6,07 mL.kg-1.min-1 quando comparado ao grupo controle (p = 0,013). Na comparação entre exercício combinado e grupo controle, foi observada uma diferença de 1,84 mL.kg-1.min-1, no entanto, sem significância (p = 0,312). Portanto, concluímos que o exercício aeróbico é a única modalidade que apresenta eficácia para aumentar o consumo de oxigênio de pico em comparação a um grupo controle.

Palavras-chave:
exercício físico; infarto agudo do miocárdio; reabilitação cardiovascular; doença da artéria coronariana; cardiopatia isquêmica

INTRODUCTION

Mortality due to cardiovascular diseases (CVDs) accounts for around 70% of deaths globally, at more than 38 million deaths per year.11 Roth GA, Johnson C, Abajobir A, et al. Global, regional, and national burden of cardiovascular diseases for 10 causes, 1990 to 2015. J Am Coll Cardiol. 2017;70(1):1-25. http://dx.doi.org/10.1016/j.jacc.2017.04.052. PMid:28527533.
http://dx.doi.org/10.1016/j.jacc.2017.04...
In Brazil, the CVD mortality rate has attained 30%.22 Martins WA, Rosa MLG, Matos RC, et al. Trends in mortality rates from cardiovascular disease and cancer between 2000 and 2015 in the most populous capital cities of the five regions of Brazil. Arq Bras Cardiol. 2020;114(2):199-206. PMid:32215484. From 2008 to 2016, the Brazilian National Health Service (SUS - Sistema Único de Saúde) performed 2,548,944 procedures involving ischemic heart diseases, ranging from clinical treatment for acute myocardial infarction (AMI) to myocardial revascularization surgery.33 Oliveira GMM, Brant LCC, Polanczyk CA, et al. Estatística cardiovascular Brasil 2020. Arq Bras Cardiol. 2020;115(3):308-439. http://dx.doi.org/10.36660/abc.20200812.
http://dx.doi.org/10.36660/abc.20200812...
In 2018, the SUS spent around R$ 3,700,000.00 on procedures involving myocardial ischemia.33 Oliveira GMM, Brant LCC, Polanczyk CA, et al. Estatística cardiovascular Brasil 2020. Arq Bras Cardiol. 2020;115(3):308-439. http://dx.doi.org/10.36660/abc.20200812.
http://dx.doi.org/10.36660/abc.20200812...
It is estimated that AMI mortality was 56% in 2017.44 Ribeiro AL, Duncan BB, Brant LC, Lotufo PA, Mill JG, Barreto SM. Cardiovascular health in Brazil: trends and perspectives. Circulation. 2016;133(4):422-33. http://dx.doi.org/10.1161/CIRCULATIONAHA.114.008727. PMid:26811272.
http://dx.doi.org/10.1161/CIRCULATIONAHA...

Acute myocardial infarction is clearly related to atherosclerotic disease load,55 Tibaut M, Mekis D, Petrovic D. Pathophysiology of myocardial infarction and acute management strategies. Cardiovasc Hematol Agents Med Chem. 2017;14(3):150-9. http://dx.doi.org/10.2174/1871525714666161216100553. PMid:27993119.
http://dx.doi.org/10.2174/18715257146661...
but is even more directly linked to acute occlusive formation of thrombosis on coronary atheromatous plaques, occluding the vessel lumen and causing myocardial necrosis.66 Marcolino MS, Brant LCC, Araujo JG, et al. Implementation of the myocardial infarction system of care in city of Belo Horizonte, Brazil. Arq Bras Cardiol. 2013;100:307-14. PMid:23545995.,77 Bertuzzi M, Negri E, Tavani A, Vecchia C. Family history of ischemic heart disease and risk of acute myocardial infarction. Prev Med. 2003;37(3):183-7. http://dx.doi.org/10.1016/S0091-7435(03)00094-X. PMid:12914823.
http://dx.doi.org/10.1016/S0091-7435(03)...
The degree of irreversibility of atherosclerosis is directly associated with advanced lesions, such as, for example, fibroatheromas.88 Joshi NV, Toor I, Shah AS, et al. Systemic atherosclerotic inflammation following acute myocardial infarction: myocardial infarction begets myocardial infarction. J Am Heart Assoc. 2015;4(9):e001956. http://dx.doi.org/10.1161/JAHA.115.001956. PMid:26316523.
http://dx.doi.org/10.1161/JAHA.115.00195...
Necrosis formed by a lipid-rich core is caused by degradation of the extracellular matrix, death of smooth muscle cells, and apoptosis of foam cells, provoking build-up of lipids.99 Crea F, Liuzzo G. Pathogenesis of acute coronary syndromes. J Am Coll Cardiol. 2013;61(1):1-11. http://dx.doi.org/10.1016/j.jacc.2012.07.064. PMid:23158526.
http://dx.doi.org/10.1016/j.jacc.2012.07...
Finally, fibroatheromas cause arterial calcification, composing part of the occlusive plaque, which is defined by presence of arterial thrombus.1010 Allahverdian S, Pannu PS, Francis GA. Contribution of monocyte-derived macrophages and smooth muscle cells to arterial foam cell formation. Cardiovasc Res. 2012;95(2):165-72. http://dx.doi.org/10.1093/cvr/cvs094. PMid:22345306.
http://dx.doi.org/10.1093/cvr/cvs094...

Post-infarction myocardial dysfunction is the predominant factor in impairment of patients’ functional capacity. Changes to the cardiac muscle’s capacity for contractility makes it unable to increase heart rate and arterial blood pressure at low levels of physical effort, reducing the double product and generating a low ischemic threshold. Cardiopulmonary exercise testing is considered the gold standard for assessment of functional capacity, in terms of peak oxygen consumption (VO2peak).1111 Madsen EB, Gilpin E, Ahnve S, Henning H, Ross J Jr. Prediction of functional capacity and use of exercise testing for predicting risk after acute myocardial infarction. Am J Cardiol. 1985;56(13):839-45. http://dx.doi.org/10.1016/0002-9149(85)90766-0. PMid:2865888.
http://dx.doi.org/10.1016/0002-9149(85)9...
,1212 Kunz VC, Serra KBS, Borges ÉN, Serra PES, Silva E. Cardiopulmonary exercise testing in the early-phase of myocardial infarction. Rev Bras Fisioter. 2012;16(5):396-405. http://dx.doi.org/10.1590/S1413-35552012005000047. PMid:23032293.
http://dx.doi.org/10.1590/S1413-35552012...
Many different studies have demonstrated that VO2peak is an independent predictor of mortality in people who have had AMI.1313 Chiaranda G, Myers J, Arena R, et al. Improved percent-predicted peak VO(2) is associated with lower risk of hospitalization in patients with coronary heart disease. Analysis from the FRIEND registry. Int J Cardiol. 2020;310:138-44. http://dx.doi.org/10.1016/j.ijcard.2020.02.057. PMid:32139240.
http://dx.doi.org/10.1016/j.ijcard.2020....

14 Siqueira CAS, Souza DLB. Reduction of mortality and predictions for acute myocardial infarction, stroke, and heart failure in Brazil until 2030. Sci Rep. 2020;10(1):17856.
-1515 Swank AM, Horton J, Fleg JL, et al. Modest increase in peak VO2 is related to better clinical outcomes in chronic heart failure patients: results from heart failure and a controlled trial to investigate outcomes of exercise training. Circ Heart Fail. 2012;5(5):579-85. http://dx.doi.org/10.1161/CIRCHEARTFAILURE.111.965186. PMid:22773109.
http://dx.doi.org/10.1161/CIRCHEARTFAILU...
Conversely, a 1 mL.kg-1.min-1 increase in VO2peak is directly associated with a 10% reduction in risk of CVD mortality.1616 Kavanagh T, Mertens DJ, Hamm LF, et al. Prediction of long-term prognosis in 12 169 men referred for cardiac rehabilitation. Circulation. 2002;106(6):666-71. http://dx.doi.org/10.1161/01.CIR.0000024413.15949.ED. PMid:12163425.
http://dx.doi.org/10.1161/01.CIR.0000024...
,1717 Kavanagh T, Mertens DJ, Hamm LF, et al. Peak oxygen intake and cardiac mortality in women referred for cardiac rehabilitation. J Am Coll Cardiol. 2003;42(12):2139-43. http://dx.doi.org/10.1016/j.jacc.2003.07.028. PMid:14680741.
http://dx.doi.org/10.1016/j.jacc.2003.07...

Physical exercise is an extremely important non-pharmaceutical tool for treating AMI, both for preventing risk factors and for increasing VO2peak.1818 Anderson L, Sharp GA, Norton RJ, et al. Home-based versus centre-based cardiac rehabilitation. Cochrane Database Syst Rev. 2017;6(6):CD007130. PMid:28665511. Aerobic exercise is the most recommended modality in current cardiac rehabilitation guidelines,1919 Pelliccia A, Sharma S, Gati S, et al. 2020 ESC Guidelines on sports cardiology and exercise in patients with cardiovascular disease. Eur Heart J. 2021;42(2):17-96. PMid:32860412.

20 Leon AS, Franklin BA, Costa F, et al. Cardiac rehabilitation and secondary prevention of coronary heart disease: an American Heart Association scientific statement from the Council on Clinical Cardiology (Subcommittee on Exercise, Cardiac Rehabilitation, and Prevention) and the Council on Nutrition, Physical Activity, and Metabolism (Subcommittee on Physical Activity), in collaboration with the American association of Cardiovascular and Pulmonary Rehabilitation. Circulation. 2005;111(3):369-76. http://dx.doi.org/10.1161/01.CIR.0000151788.08740.5C. PMid:15668354.
http://dx.doi.org/10.1161/01.CIR.0000151...
-2121 Carvalho T, Milani M, Ferraz AS, et al. Brazilian cardiovascular rehabilitation guideline - 2020. Arq Bras Cardiol. 2020;114(5):943-87. http://dx.doi.org/10.36660/abc.20200407. PMid:32491079.
http://dx.doi.org/10.36660/abc.20200407...
because it is the simplest to perform outside of a hospital environment and does not require equipment.2222 Peixoto TC, Begot I, Bolzan DW, et al. Early exercise-based rehabilitation improves health-related quality of life and functional capacity after acute myocardial infarction: a randomized controlled trial. Can J Cardiol. 2015;31(3):308-13. http://dx.doi.org/10.1016/j.cjca.2014.11.014. PMid:25633911.
http://dx.doi.org/10.1016/j.cjca.2014.11...
With regard to efficacy, aerobic exercise appears to deliver similar results in terms of VO2peak, compared to other methods, such as, for example, combined exercise (aerobic + strength exercises in the same session),2323 Pierson LM, Herbert WG, Norton HJ, et al. Effects of combined aerobic and resistance training versus aerobic training alone in cardiac rehabilitation. J Cardiopulm Rehabil. 2001;21(2):101-10. http://dx.doi.org/10.1097/00008483-200103000-00007. PMid:11314283.
http://dx.doi.org/10.1097/00008483-20010...
and superior results to strength exercises.2424 Meka N, Katragadda S, Cherian B, Arora RR. Endurance exercise and resistance training in cardiovascular disease. Ther Adv Cardiovasc Dis. 2008;2(2):115-21. http://dx.doi.org/10.1177/1753944708089701. PMid:19124415.
http://dx.doi.org/10.1177/17539447080897...
However, there is a gap in the literature in relation to comparisons of the efficacy of different types of physical training for improving VO2peak in people who have had AMI. In view of this, the objective of the present study was to conduct a meta-analysis comparing the effects of different types of physical training on the VO2peak of post-AMI patients.

METHODS

Study characteristics

The study design is a systematic review with meta-analysis. Recommendations proposed by the Cochrane Collaboration2525 Higgins JPT, Deeks JJ, Altman DG. Cochrane handbook for systematic reviews of interventions, version 5.1. Oxford: Cochrane Collaboration; 2011. and the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) statement were followed.2626 Moher D, Liberati A, Tetzlaff J, Altman DG. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA Statement. Open Med. 2009;3(3):e123-30. PMid:21603045. The review was registered in advance with the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42020182666).

Eligibility criteria

The review included randomized clinical trials assessing the effect of physical exercise on VO2peak in patients who had had AMI, with no limits on age or sex. Additionally, studies were also included that subjected patients to myocardial/endovascular revascularization surgery or conservative treatment with antithrombotic medications to treat the ischemic condition.

Physical exercise modalities were restricted to three types: aerobic exercise, strength exercises, and combined exercise, with no restriction in relation to the type of exercise, instruments, intensity, session duration, weekly frequency, volume, or rest interval. The minimum intervention duration was set at 6 weeks, considered the minimum time necessary for a positive effect on VO2peak in post-AMI patients, and exercise should be supervised.

Additionally, studies should report comparisons of results with groups of patients who did not perform exercise (control group) or performed the exercise recommended by guidelines (literature standard control group –moderate intensity aerobic exercise). Only studies that did not report significant differences between the groups before the follow-up period started were included. No publication date limits were imposed and studies published in English and Portuguese were included in the analysis.

Exclusion criteria

Studies comparing surgical techniques with non-surgical techniques were excluded from this systematic review. Observational studies and studies that did not report sufficient data for data extraction were also excluded.

DATA COLLECTION PROCEDURES

Search strategy

Initially, articles were filtered using EndNote software to exclude duplicates. Titles and abstracts were then independently analyzed against the eligibility criteria by two experienced assessors. After article selection, the full texts of studies that met the eligibility criteria were analyzed. No publication date filter was applied, in order to include a larger range of studies.

We used the following electronic databases: PubMed (MEDLINE – US National Library of Medicine), Cochrane Library, Scopus, and Pedro (Physiotherapy Evidence Database). Manual searches of the reference lists of studies included in the review were also conducted. No filter was set to select randomized clinical trials, since the decision had been made to initially include more studies, to widen the scope of the literature on the subject reviewed. Selection on the basis of study design was performed manually. Abstracts and extended abstracts published in conference annals, dissertations, theses, and studies not yet published in journals (pre-print) were not included.

A PICO question was constructed to define the search string and guide the study selection strategy:

Population: patients with acute myocardial infarction;

Intervention: physical exercise (aerobic, strength, or combined);

Comparison: control group, placebo, or aerobic exercise;

Outcomes: peak oxygen consumption.

The search string used for PubMed was as follows:

Population: “Myocardial Infarction”[Mesh] OR “Infarction, Myocardial” OR “Infarcts, Myocardial” OR “Myocardial Infarcts” OR “Cardiovascular Stroke” OR “Cardiovascular Strokes” OR “Stroke, Cardiovascular” OR “Strokes, Cardiovascular” OR “Myocardial Infarct” OR “Infarct, Myocardial” OR “Infarcts, Myocardial” OR “Myocardial Infarcts” OR “Heart Attack” OR “Heart Attacks”

Intervention: “Exercise”[Mesh] OR “Exercises” OR “Physical Activity” OR “Activities, Physical” OR “Activity, Physical” OR “Physical Activities” OR “Exercise, Physical” OR “Exercises, Physical” OR “Physical Exercise” OR “Physical Exercises” OR “Acute Exercise” OR “Acute Exercises” OR “Exercise, Acute” OR “Exercises, Acute” OR “Exercise, Isometric” OR “Exercises, Isometric” OR “Isometric Exercises” OR “Isometric Exercise” OR “Exercise, Aerobic” OR “Aerobic Exercise” OR “Aerobic Exercises” OR “Exercises, Aerobic” OR “Exercise Training” OR “Exercise Trainings” OR “Training, Exercise” OR “Trainings, Exercise” OR “Resistance Training”[Mesh] OR “Training, Resistance” OR “Strength Training” OR “Training, Strength” OR “Weight-Lifting Strengthening Program” OR “Strengthening Program, Weight-Lifting” OR “Strengthening Programs, Weight-Lifting” OR “Weight Lifting Strengthening Program” OR “Weight-Lifting Strengthening Programs” OR “Weight-Lifting Exercise Program” OR “Exercise Program, Weight-Lifting” OR “Exercise Programs, Weight-Lifting” OR “Weight Lifting Exercise Program” OR “Weight-Lifting Exercise Programs” OR “Weight-Bearing Strengthening Program” OR “Weight-Bearing Strengthening Program” OR “Strengthening Program, Weight-Bearing” OR “Strengthening Programs, Weight-Bearing” OR “Weight Bearing Strengthening Program” OR “Weight-Bearing Strengthening Programs” OR “Weight-Bearing Exercise Program” OR “Exercise Program, Weight-Bearing” OR “Exercise Programs, Weight-Bearing” OR “Weight Bearing Exercise Program” OR “Weight-Bearing Exercise Programs”.

We decided not to include outcomes in the search string, in order to include a wide range of literature on the central subject, including only population and intervention.

In the other databases we only used the MeSH terms “Myocardial Infarction”, “Exercise”, and “Resistance Training”, since it is unnecessary to include all the other terms for Cochrane Library, Pedro, or SciELO.

SELECTION OF STUDIES AND DATA EXTRACTION

Two independent reviewers (GB and KRJ) assessed the titles and abstracts of all the articles identified by the search strategy. The full texts of all articles selected and any with respect to which there was any doubt were then read by the same two independent assessors, applying the criteria for inclusion and exclusion of the studies. Any discrepancies between these two assessors’ decisions were resolved by consensus. In cases of disagreement or doubt, a third evaluator (LTF) was available to decide on inclusion or exclusion of the study in question.

The same independent assessors performed data extraction. A standardized form was constructed, indicating the information that should be extracted, including, for example, sample characteristics, relevant clinical information, such as time since AMI, medications used, and complete and detailed descriptions of the interventions administered. The following data were extracted: year of study, sample size, sex, number of men, number of women, mean age, standard deviation of age, mean body mass, standard deviation of body mass, mean body mass index (BMI), standard deviation of BMI, characteristics of groups, time since AMI, type of surgery, medications, type of training, weekly frequency, duration of follow-up, progression, series, repetitions, intensity, interval, and volume. Additionally, data were extracted on the primary outcome of the study and VO2peak (mean and standard deviation for pre and post-intervention periods).

ASSESSMENT OF METHODOLOGICAL QUALITY (RISK OF BIAS)

Cochrane Collaboration recommendations were followed with relation to evaluation of methodological quality,2525 Higgins JPT, Deeks JJ, Altman DG. Cochrane handbook for systematic reviews of interventions, version 5.1. Oxford: Cochrane Collaboration; 2011. extracting data on: generation of randomization sequence, allocation concealment, blinding of patient and therapist, blinding of outcome examiners, description of losses and exclusions, and incomplete outcome data. Two independent reviewers participated in this phase of the assessment (ELG and LTF), and for each criterion the studies were classified as high risk (if the criterion was not present), low risk (if the criterion was present), or unclear risk (if the criterion was not reported).

ANALYSIS OF THE DATA

Results are expressed as standardized mean difference in absolute values between interventions with the 95% confidence interval (95%CI). Statistical heterogeneity of the effects of interventions between studies was assessed by the Cochran Q test and the I2 test of inconsistency, for which values exceeding 50% indicate high heterogeneity.2727 Higgins JP, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-analyses. BMJ. 2003;327(7414):557-60. http://dx.doi.org/10.1136/bmj.327.7414.557. PMid:12958120.
http://dx.doi.org/10.1136/bmj.327.7414.5...
The random effects model was employed. The meta-analysis analyzed values for comparisons of VO2peak, expressed in mL.kg-.11 Roth GA, Johnson C, Abajobir A, et al. Global, regional, and national burden of cardiovascular diseases for 10 causes, 1990 to 2015. J Am Coll Cardiol. 2017;70(1):1-25. http://dx.doi.org/10.1016/j.jacc.2017.04.052. PMid:28527533.
http://dx.doi.org/10.1016/j.jacc.2017.04...
min-1, for aerobic exercise vs. control and combined exercise vs. control. Results with α ≤ 0.05 were considered statistically significant. All analyses were conducted using Comprehensive Meta-Analysis version 2.0 (Englewood, New Jersey, USA).

RESULTS

Eight of the 4,586 studies identified met the inclusion criteria (Figure 1). However, the VO2peak data from one study were reported in L.min-1 and another was not randomized.2828 Takagi S, Murase N, Kime R, Niwayama M, Osada T, Katsumura T. Aerobic training enhances muscle deoxygenation in early post-myocardial infarction. Eur J Appl Physiol. 2016;116(4):673-85. http://dx.doi.org/10.1007/s00421-016-3326-x. PMid:26759155.
http://dx.doi.org/10.1007/s00421-016-332...
,2929 Arthur HM, Gunn E, Thorpe KE, et al. Effect of aerobic vs combined aerobic-strength training on 1-year, post-cardiac rehabilitation outcomes in women after a cardiac event. J Rehabil Med. 2007;39(9):730-5. http://dx.doi.org/10.2340/16501977-0122. PMid:17999012.
http://dx.doi.org/10.2340/16501977-0122...
After the authors of the first of these studies were contacted, they stated that they did not have data in mL.kg-1.min-1, which is the standardized measure for expressing this variable. As a result, six studies were included in the quantitative analysis.3030 Benetti M, Araujo CL, Santos RZ. Cardiorespiratory fitness and quality of life at different exercise intensities after myocardial infarction. Arq Bras Cardiol. 2010;95(3):399-404. http://dx.doi.org/10.1590/S0066-782X2010005000089. PMid:20640381.
http://dx.doi.org/10.1590/S0066-782X2010...

31 Khalid Z, Farheen H, Tariq MI, Amjad I. Effectiveness of resistance interval training versus aerobic interval training on peak oxygen uptake in patients with myocardial infarction. J Pak Med Assoc. 2019;69(8):1194-8. PMid:31431779.

32 Santi GLD, Moreira HT, Carvalho EEV, et al. Influence of aerobic training on the mechanics of ventricular contraction after acute myocardial infarction: a pilot study. Arq Bras Cardiol. 2018;110(4):383-7. http://dx.doi.org/10.5935/abc.20180049. PMid:29791580.
http://dx.doi.org/10.5935/abc.20180049...

33 Oliveira NL, Ribeiro F, Teixeira M, et al. Effect of 8-week exercise-based cardiac rehabilitation on cardiac autonomic function: a randomized controlled trial in myocardial infarction patients. Am Heart J. 2014;167(5):753-61. http://dx.doi.org/10.1016/j.ahj.2014.02.001. PMid:24766987.
http://dx.doi.org/10.1016/j.ahj.2014.02....

34 Trachsel LD, David LP, Gayda M, et al. The impact of high-intensity interval training on ventricular remodeling in patients with a recent acute myocardial infarction - a randomized training intervention pilot study. Clin Cardiol. 2019;42(12):1222-31. http://dx.doi.org/10.1002/clc.23277.
http://dx.doi.org/10.1002/clc.23277...
-3535 Moholdt T, Aamot IL, Granøien I, et al. Aerobic interval training increases peak oxygen uptake more than usual care exercise training in myocardial infarction patients: a randomized controlled study. Clin Rehabil. 2012;26(1):33-44. http://dx.doi.org/10.1177/0269215511405229. PMid:21937520.
http://dx.doi.org/10.1177/02692155114052...
Two of these were included twice3030 Benetti M, Araujo CL, Santos RZ. Cardiorespiratory fitness and quality of life at different exercise intensities after myocardial infarction. Arq Bras Cardiol. 2010;95(3):399-404. http://dx.doi.org/10.1590/S0066-782X2010005000089. PMid:20640381.
http://dx.doi.org/10.1590/S0066-782X2010...
,3232 Santi GLD, Moreira HT, Carvalho EEV, et al. Influence of aerobic training on the mechanics of ventricular contraction after acute myocardial infarction: a pilot study. Arq Bras Cardiol. 2018;110(4):383-7. http://dx.doi.org/10.5935/abc.20180049. PMid:29791580.
http://dx.doi.org/10.5935/abc.20180049...
because they met eligibility criteria for two comparisons between groups: aerobic exercise of moderate intensity vs. control and aerobic exercise of high intensity vs. control. Additionally, two studies met the eligibility criteria for comparison of combined exercise vs. control (aerobic training).

Figure 1
Study flow diagram illustrating all steps in the systematic review and meta-analysis.

Overall, 361 participants were included in the meta-analysis. Of these, 155 were allocated to an aerobic exercise group (AEG), 35 to a combined exercise group (CEG), and 171 to a control group (CG). Fifty per cent of the studies analyzed male patients only,3030 Benetti M, Araujo CL, Santos RZ. Cardiorespiratory fitness and quality of life at different exercise intensities after myocardial infarction. Arq Bras Cardiol. 2010;95(3):399-404. http://dx.doi.org/10.1590/S0066-782X2010005000089. PMid:20640381.
http://dx.doi.org/10.1590/S0066-782X2010...
,3333 Oliveira NL, Ribeiro F, Teixeira M, et al. Effect of 8-week exercise-based cardiac rehabilitation on cardiac autonomic function: a randomized controlled trial in myocardial infarction patients. Am Heart J. 2014;167(5):753-61. http://dx.doi.org/10.1016/j.ahj.2014.02.001. PMid:24766987.
http://dx.doi.org/10.1016/j.ahj.2014.02....
,3434 Trachsel LD, David LP, Gayda M, et al. The impact of high-intensity interval training on ventricular remodeling in patients with a recent acute myocardial infarction - a randomized training intervention pilot study. Clin Cardiol. 2019;42(12):1222-31. http://dx.doi.org/10.1002/clc.23277.
http://dx.doi.org/10.1002/clc.23277...
33% analyzed people of both sexes, and just one study (17%) did not report the sex of its sample. The total number of women was 35 (9.7%).

Two studies (33%) studied samples comprising a sedentary group with a history of obesity.3030 Benetti M, Araujo CL, Santos RZ. Cardiorespiratory fitness and quality of life at different exercise intensities after myocardial infarction. Arq Bras Cardiol. 2010;95(3):399-404. http://dx.doi.org/10.1590/S0066-782X2010005000089. PMid:20640381.
http://dx.doi.org/10.1590/S0066-782X2010...
,3333 Oliveira NL, Ribeiro F, Teixeira M, et al. Effect of 8-week exercise-based cardiac rehabilitation on cardiac autonomic function: a randomized controlled trial in myocardial infarction patients. Am Heart J. 2014;167(5):753-61. http://dx.doi.org/10.1016/j.ahj.2014.02.001. PMid:24766987.
http://dx.doi.org/10.1016/j.ahj.2014.02....
Additionally, 50% exhibited risk factors such as diabetes mellitus, systemic arterial hypertension, dyslipidemia, and history of smoking.3131 Khalid Z, Farheen H, Tariq MI, Amjad I. Effectiveness of resistance interval training versus aerobic interval training on peak oxygen uptake in patients with myocardial infarction. J Pak Med Assoc. 2019;69(8):1194-8. PMid:31431779.,3333 Oliveira NL, Ribeiro F, Teixeira M, et al. Effect of 8-week exercise-based cardiac rehabilitation on cardiac autonomic function: a randomized controlled trial in myocardial infarction patients. Am Heart J. 2014;167(5):753-61. http://dx.doi.org/10.1016/j.ahj.2014.02.001. PMid:24766987.
http://dx.doi.org/10.1016/j.ahj.2014.02....

34 Trachsel LD, David LP, Gayda M, et al. The impact of high-intensity interval training on ventricular remodeling in patients with a recent acute myocardial infarction - a randomized training intervention pilot study. Clin Cardiol. 2019;42(12):1222-31. http://dx.doi.org/10.1002/clc.23277.
http://dx.doi.org/10.1002/clc.23277...
-3535 Moholdt T, Aamot IL, Granøien I, et al. Aerobic interval training increases peak oxygen uptake more than usual care exercise training in myocardial infarction patients: a randomized controlled study. Clin Rehabil. 2012;26(1):33-44. http://dx.doi.org/10.1177/0269215511405229. PMid:21937520.
http://dx.doi.org/10.1177/02692155114052...
Aerobic exercise was the most prevalent modality among the six studies (66%) and two of the four studies of aerobic exercise were included twice, because they investigated different exercise intensities. Moderate intensity was used in three of these four studies (75%),3030 Benetti M, Araujo CL, Santos RZ. Cardiorespiratory fitness and quality of life at different exercise intensities after myocardial infarction. Arq Bras Cardiol. 2010;95(3):399-404. http://dx.doi.org/10.1590/S0066-782X2010005000089. PMid:20640381.
http://dx.doi.org/10.1590/S0066-782X2010...
,3232 Santi GLD, Moreira HT, Carvalho EEV, et al. Influence of aerobic training on the mechanics of ventricular contraction after acute myocardial infarction: a pilot study. Arq Bras Cardiol. 2018;110(4):383-7. http://dx.doi.org/10.5935/abc.20180049. PMid:29791580.
http://dx.doi.org/10.5935/abc.20180049...
,3333 Oliveira NL, Ribeiro F, Teixeira M, et al. Effect of 8-week exercise-based cardiac rehabilitation on cardiac autonomic function: a randomized controlled trial in myocardial infarction patients. Am Heart J. 2014;167(5):753-61. http://dx.doi.org/10.1016/j.ahj.2014.02.001. PMid:24766987.
http://dx.doi.org/10.1016/j.ahj.2014.02....
and high intensity was used in three studies (75%).3030 Benetti M, Araujo CL, Santos RZ. Cardiorespiratory fitness and quality of life at different exercise intensities after myocardial infarction. Arq Bras Cardiol. 2010;95(3):399-404. http://dx.doi.org/10.1590/S0066-782X2010005000089. PMid:20640381.
http://dx.doi.org/10.1590/S0066-782X2010...
,3232 Santi GLD, Moreira HT, Carvalho EEV, et al. Influence of aerobic training on the mechanics of ventricular contraction after acute myocardial infarction: a pilot study. Arq Bras Cardiol. 2018;110(4):383-7. http://dx.doi.org/10.5935/abc.20180049. PMid:29791580.
http://dx.doi.org/10.5935/abc.20180049...
,3535 Moholdt T, Aamot IL, Granøien I, et al. Aerobic interval training increases peak oxygen uptake more than usual care exercise training in myocardial infarction patients: a randomized controlled study. Clin Rehabil. 2012;26(1):33-44. http://dx.doi.org/10.1177/0269215511405229. PMid:21937520.
http://dx.doi.org/10.1177/02692155114052...
Combined exercise was used in two studies (34%), both of which used high intensity aerobic exercise as part of combined exercise.3131 Khalid Z, Farheen H, Tariq MI, Amjad I. Effectiveness of resistance interval training versus aerobic interval training on peak oxygen uptake in patients with myocardial infarction. J Pak Med Assoc. 2019;69(8):1194-8. PMid:31431779.,3434 Trachsel LD, David LP, Gayda M, et al. The impact of high-intensity interval training on ventricular remodeling in patients with a recent acute myocardial infarction - a randomized training intervention pilot study. Clin Cardiol. 2019;42(12):1222-31. http://dx.doi.org/10.1002/clc.23277.
http://dx.doi.org/10.1002/clc.23277...

Mean duration of the intervention programs was 10.33 ± 2.66 weeks, mean weekly frequency was 3.17 ± 0.98, and mean duration of sessions was 45.83 ± 9.52 minutes. Sixty-six percent of the six studies included reported mean time since participants had suffered AMI (22 ± 21 weeks). Table 1 summarizes the main characteristics of the studies included. Table 2 lists aspects related to risk of bias.

Table 1
Characteristics of studies included in data extraction.
Table 2
Extraction of risk of bias.

EFFECTS OF THE INTERVENTIONS

Aerobic exercise vs. Control (with and without intervention)

A total of 290 participants were assessed (Figure 2), 155 in the AEG and 135 in the CG. Aerobic exercise was associated with a mean increase of 6.07 mL.kg-1.min-1 (95%CI 1.27 to 10.86; I2: 88%) when compared to CG (p = 0.013).

Figure 2
Standardized mean differences in peak oxygen consumption (mL.kg-1.min- ) observed between aerobic exercise group and control group.

Combined Exercise vs. Control (without intervention)

Seventy-one participants were assessed (Figure 3), 35 in the CEG and 36 in the CG. Combined exercise did not result in a statistically significant difference when compared with the CG. Combined exercise did, nevertheless, result in a mean increase of 1.84 mL.kg-1.min-1 (95%CI -1.73 to 5.42; I2: 0%) when compared to the CG (p = 0.312).

Figure 3
Standardized mean differences in peak oxygen consumption (mL.kg-1.min- ) observed between combined exercise group and control group.

DISCUSSION

This study conducted a meta-analysis to investigate the effects of different types of physical training on the VO2peak of individuals who had suffered an AMI. The main finding is that aerobic exercise was associated with a mean VO2peak increase of 6 mL.kg-1.min-1 compared with the CG, which was a statistically significant difference (p = 0.013).

Although this systematic review investigated the effects of different types of physical training, it is important to stress that very few studies have investigated the effects of combined exercise on the VO2peak of individuals who have suffered AMI3131 Khalid Z, Farheen H, Tariq MI, Amjad I. Effectiveness of resistance interval training versus aerobic interval training on peak oxygen uptake in patients with myocardial infarction. J Pak Med Assoc. 2019;69(8):1194-8. PMid:31431779.,3434 Trachsel LD, David LP, Gayda M, et al. The impact of high-intensity interval training on ventricular remodeling in patients with a recent acute myocardial infarction - a randomized training intervention pilot study. Clin Cardiol. 2019;42(12):1222-31. http://dx.doi.org/10.1002/clc.23277.
http://dx.doi.org/10.1002/clc.23277...
and that no studies have investigated the effects of strength exercises on VO2peak. In contrast, the modality most investigated in these studies was aerobic exercise (66%).3030 Benetti M, Araujo CL, Santos RZ. Cardiorespiratory fitness and quality of life at different exercise intensities after myocardial infarction. Arq Bras Cardiol. 2010;95(3):399-404. http://dx.doi.org/10.1590/S0066-782X2010005000089. PMid:20640381.
http://dx.doi.org/10.1590/S0066-782X2010...
,3232 Santi GLD, Moreira HT, Carvalho EEV, et al. Influence of aerobic training on the mechanics of ventricular contraction after acute myocardial infarction: a pilot study. Arq Bras Cardiol. 2018;110(4):383-7. http://dx.doi.org/10.5935/abc.20180049. PMid:29791580.
http://dx.doi.org/10.5935/abc.20180049...
,3333 Oliveira NL, Ribeiro F, Teixeira M, et al. Effect of 8-week exercise-based cardiac rehabilitation on cardiac autonomic function: a randomized controlled trial in myocardial infarction patients. Am Heart J. 2014;167(5):753-61. http://dx.doi.org/10.1016/j.ahj.2014.02.001. PMid:24766987.
http://dx.doi.org/10.1016/j.ahj.2014.02....
,3535 Moholdt T, Aamot IL, Granøien I, et al. Aerobic interval training increases peak oxygen uptake more than usual care exercise training in myocardial infarction patients: a randomized controlled study. Clin Rehabil. 2012;26(1):33-44. http://dx.doi.org/10.1177/0269215511405229. PMid:21937520.
http://dx.doi.org/10.1177/02692155114052...
Moreover, high intensity aerobic exercise was used as the CG in the two studies that investigated combined exercise. Our findings therefore corroborate the literature that indicates aerobic exercise as the most used modality for rehabilitation of patients who have suffered an AMI.1919 Pelliccia A, Sharma S, Gati S, et al. 2020 ESC Guidelines on sports cardiology and exercise in patients with cardiovascular disease. Eur Heart J. 2021;42(2):17-96. PMid:32860412.,2020 Leon AS, Franklin BA, Costa F, et al. Cardiac rehabilitation and secondary prevention of coronary heart disease: an American Heart Association scientific statement from the Council on Clinical Cardiology (Subcommittee on Exercise, Cardiac Rehabilitation, and Prevention) and the Council on Nutrition, Physical Activity, and Metabolism (Subcommittee on Physical Activity), in collaboration with the American association of Cardiovascular and Pulmonary Rehabilitation. Circulation. 2005;111(3):369-76. http://dx.doi.org/10.1161/01.CIR.0000151788.08740.5C. PMid:15668354.
http://dx.doi.org/10.1161/01.CIR.0000151...

A total of 361 participants were included in this meta-analysis, 296 of whom were men, which underscores the prevalence of AMI among men.44 Ribeiro AL, Duncan BB, Brant LC, Lotufo PA, Mill JG, Barreto SM. Cardiovascular health in Brazil: trends and perspectives. Circulation. 2016;133(4):422-33. http://dx.doi.org/10.1161/CIRCULATIONAHA.114.008727. PMid:26811272.
http://dx.doi.org/10.1161/CIRCULATIONAHA...
It is therefore important to emphasize that one of the risk factors for development of this disease is sex, in addition to age group.55 Tibaut M, Mekis D, Petrovic D. Pathophysiology of myocardial infarction and acute management strategies. Cardiovasc Hematol Agents Med Chem. 2017;14(3):150-9. http://dx.doi.org/10.2174/1871525714666161216100553. PMid:27993119.
http://dx.doi.org/10.2174/18715257146661...
The main physiological protective factor in women is estrogen, a hormone directly related to cardiovascular protection.3636 Iorga A, Cunningham CM, Moazeni S, Ruffenach G, Umar S, Eghbali M. The protective role of estrogen and estrogen receptors in cardiovascular disease and the controversial use of estrogen therapy. Biol Sex Differ. 2017;8(1):33. http://dx.doi.org/10.1186/s13293-017-0152-8. PMid:29065927.
http://dx.doi.org/10.1186/s13293-017-015...
In addition to sex, AMI affects people from 40-45 years of age onwards. At this age, women’s estrogen production is maintained. The highest incidence of AMI among women is after menopause, when there is a considerable drop in estrogen production.3636 Iorga A, Cunningham CM, Moazeni S, Ruffenach G, Umar S, Eghbali M. The protective role of estrogen and estrogen receptors in cardiovascular disease and the controversial use of estrogen therapy. Biol Sex Differ. 2017;8(1):33. http://dx.doi.org/10.1186/s13293-017-0152-8. PMid:29065927.
http://dx.doi.org/10.1186/s13293-017-015...

It has been shown that aerobic exercise is effective for reducing risk factors and for increasing functional capacity in middle-aged or elderly people with a range of CVDs.2222 Peixoto TC, Begot I, Bolzan DW, et al. Early exercise-based rehabilitation improves health-related quality of life and functional capacity after acute myocardial infarction: a randomized controlled trial. Can J Cardiol. 2015;31(3):308-13. http://dx.doi.org/10.1016/j.cjca.2014.11.014. PMid:25633911.
http://dx.doi.org/10.1016/j.cjca.2014.11...
,3737 Franzoni L, Stein R. Moderate exercise improves depressive symptoms and pain in elderly people. Int J Cardiovasc Sci. 2019;32(6):563-4. Physical training programs including aerobic exercise are important to provoke positive adaptations in the VO2peak of people who have suffered an AMI. However, it is essential to manage the intensity of exercise to achieve the desired results during an intervention.3838 Stein R, Franzoni LT. Digital tools and cardiovascular rehabilitation. Int J Cardiovasc Sci. 2018;31(6):558-9. High intensity aerobic exercise appears to deliver the greatest increase in VO2peak (14.7 mL.kg-1.min-1).3030 Benetti M, Araujo CL, Santos RZ. Cardiorespiratory fitness and quality of life at different exercise intensities after myocardial infarction. Arq Bras Cardiol. 2010;95(3):399-404. http://dx.doi.org/10.1590/S0066-782X2010005000089. PMid:20640381.
http://dx.doi.org/10.1590/S0066-782X2010...
High intensity (at 85-95% of VO2peak) is associated with good adherence to intervention programs using physical exercises and is also linked with increased oxidative capacity of the muscles and glucose transport capacity, improving insulin sensitivity and glycemic control as a consequence.3939 Liu JX, Zhu L, Li PJ, Li N, Xu YB. Effectiveness of high-intensity interval training on glycemic control and cardiorespiratory fitness in patients with type 2 diabetes: a systematic review and meta-analysis. Aging Clin Exp Res. 2019;31(5):575-93. http://dx.doi.org/10.1007/s40520-018-1012-z. PMid:30097811.
http://dx.doi.org/10.1007/s40520-018-101...
The principal mechanism of adaptation in response to high intensity exercise is related to peroxisome proliferator-activated receptor gamma coactivator 1-alpha, the most important regulator of mitochondrial biogenesis in muscle.4040 Li J, Li Y, Atakan MM. The molecular adaptive responses of skeletal muscle to high-intensity exercise/training and hypoxia. Antioxidants. 2020;9(8):656.

The regulator mechanism of moderate intensity aerobic exercise appears to be similar. The central aspect is mitochondrial biogenesis, an important cellular organelle responsible for the oxidative activity of muscles.4141 Menshikova EV, Ritov VB, Fairfull L, Ferrell RE, Kelley DE, Goodpaster BH. Effects of exercise on mitochondrial content and function in aging human skeletal muscle. J Gerontol A Biol Sci Med Sci. 2006;61(6):534-40. http://dx.doi.org/10.1093/gerona/61.6.534. PMid:16799133.
http://dx.doi.org/10.1093/gerona/61.6.53...
,4242 Distefano G, Goodpaster BH. Effects of exercise and aging on skeletal muscle. Cold Spring Harb Perspect Med. 2018;8(3):a029785. http://dx.doi.org/10.1101/cshperspect.a029785. PMid:28432116.
http://dx.doi.org/10.1101/cshperspect.a0...
Apparently, 6 weeks of moderate intensity aerobic exercise are needed to provoke increases in both the size and the number of mitochondria, increasing the capacity for resynthesis of adenosine triphosphate. This corroborates one of the inclusion criteria for the present study, since a minimum of 6 weeks of intervention was established.4343 Clark JE. The impact of duration on effectiveness of exercise, the implication for periodization of training and goal setting for individuals who are overfat, a meta-analysis. Biol Sport. 2016;33(4):309-33. http://dx.doi.org/10.5604/20831862.1212974. PMid:28090136.
http://dx.doi.org/10.5604/20831862.12129...
Moreover, aerobic exercise in general increases arteriovenous oxygen difference, which is directly related to increased VO2peak, via greater peripheral oxygen supply, as a result of production of catecholamines and greater bioavailability of nitric oxide.4444 Detry JM, Rousseau M, Vandenbroucke G, Kusumi F, Brasseur LA, Bruce RA. Increased arteriovenous oxygen difference after physical training in coronary heart disease. Circulation. 1971;44(1):109-18. http://dx.doi.org/10.1161/01.CIR.44.1.109. PMid:5561413.
http://dx.doi.org/10.1161/01.CIR.44.1.10...
,4545 Di Francesco Marino S, Sciartilli A, Di Valerio V, Di Baldassarre A, Gallina S. The effect of physical exercise on endothelial function. Sports Med. 2009;39(10):797-812. http://dx.doi.org/10.2165/11317750-000000000-00000. PMid:19757859.
http://dx.doi.org/10.2165/11317750-00000...
Cardiac function also exhibits improved performance after an intervention with aerobic exercise, with increased diastolic filling and a concomitant combination of increased preload and optimized myocardium relaxation.4646 Garcia EL, Menezes MG, Stefani CM, Danzmann LC, Torres MA. Ergospirometry and echocardiography in early stage of heart failure with preserved ejection fraction and in healthy individuals. Arq Bras Cardiol. 2015;105(3):248-55. PMid:26247247. The improved cardiac function will provoke important benefits for reduction of diastole duration and more efficient diastolic filling.4646 Garcia EL, Menezes MG, Stefani CM, Danzmann LC, Torres MA. Ergospirometry and echocardiography in early stage of heart failure with preserved ejection fraction and in healthy individuals. Arq Bras Cardiol. 2015;105(3):248-55. PMid:26247247.

From a clinical point of view, the main finding of this study corroborates the literature on the role of rehabilitation with aerobic exercises of patients who have suffered AMI, utilizing moderate intensity as a preference,4747 Arena R, Sietsema KE. Cardiopulmonary exercise testing in the clinical evaluation of patients with heart and lung disease. Circulation. 2011;123(6):668-80. http://dx.doi.org/10.1161/CIRCULATIONAHA.109.914788. PMid:21321183.
http://dx.doi.org/10.1161/CIRCULATIONAHA...
since the several guidelines have recommendation strength I with evidence level A; i.e., this modality is highly recommended for several different CVDs.1919 Pelliccia A, Sharma S, Gati S, et al. 2020 ESC Guidelines on sports cardiology and exercise in patients with cardiovascular disease. Eur Heart J. 2021;42(2):17-96. PMid:32860412.

20 Leon AS, Franklin BA, Costa F, et al. Cardiac rehabilitation and secondary prevention of coronary heart disease: an American Heart Association scientific statement from the Council on Clinical Cardiology (Subcommittee on Exercise, Cardiac Rehabilitation, and Prevention) and the Council on Nutrition, Physical Activity, and Metabolism (Subcommittee on Physical Activity), in collaboration with the American association of Cardiovascular and Pulmonary Rehabilitation. Circulation. 2005;111(3):369-76. http://dx.doi.org/10.1161/01.CIR.0000151788.08740.5C. PMid:15668354.
http://dx.doi.org/10.1161/01.CIR.0000151...
-2121 Carvalho T, Milani M, Ferraz AS, et al. Brazilian cardiovascular rehabilitation guideline - 2020. Arq Bras Cardiol. 2020;114(5):943-87. http://dx.doi.org/10.36660/abc.20200407. PMid:32491079.
http://dx.doi.org/10.36660/abc.20200407...
The mean increase of 6 mL.kg-1.min-1 in VO2peak – the main finding of this study – demonstrates that physical exercise plays a fundamental role in reducing the risk of mortality from CVDs, since an increase of one unit of VO2peak represents a 10% reduction in the risk of CVD mortality.1616 Kavanagh T, Mertens DJ, Hamm LF, et al. Prediction of long-term prognosis in 12 169 men referred for cardiac rehabilitation. Circulation. 2002;106(6):666-71. http://dx.doi.org/10.1161/01.CIR.0000024413.15949.ED. PMid:12163425.
http://dx.doi.org/10.1161/01.CIR.0000024...
,1717 Kavanagh T, Mertens DJ, Hamm LF, et al. Peak oxygen intake and cardiac mortality in women referred for cardiac rehabilitation. J Am Coll Cardiol. 2003;42(12):2139-43. http://dx.doi.org/10.1016/j.jacc.2003.07.028. PMid:14680741.
http://dx.doi.org/10.1016/j.jacc.2003.07...
Furthermore, the 6 mL.kg-1.min-1 difference could increase patients’ autonomy to perform their daily activities, since this difference can constitute a change in functional class, whether New York Heart Association (NYHA) or the Weber class, whereby, for example, a patient at NYHA class III and Weber class C could attain NYHA class I and Weber class A.4747 Arena R, Sietsema KE. Cardiopulmonary exercise testing in the clinical evaluation of patients with heart and lung disease. Circulation. 2011;123(6):668-80. http://dx.doi.org/10.1161/CIRCULATIONAHA.109.914788. PMid:21321183.
http://dx.doi.org/10.1161/CIRCULATIONAHA...
,4848 Belli KC, Silva PFD, Franzoni LT, Myers J, Stein R, Ribeiro JP. Speed and grade increment during cardiopulmonary treadmill testing: impact on exercise prescription. Int J Cardiovasc Sci. 2019;32:374-83. http://dx.doi.org/10.5935/2359-4802.20190058.
http://dx.doi.org/10.5935/2359-4802.2019...
The finding of the present study is therefore extremely relevant to cardiovascular rehabilitation.

Although combined exercise did not exhibit significant differences compared to the CG (p = 0.312), it must be emphasized that only two studies using this type of intervention were included, which could be extremely relevant to not detecting significance. The mean difference in increase in VO2peak for combined exercise compared with the CG was 1.84 mL.kg-1.min-1. The combination of aerobic exercise and strength exercises in the same session appears to be a promising strategy – since in addition to promoting improved VO2peak, several studies point to the importance of combined exercise for improving neuromuscular aspects related to balance and muscle strength, primarily as a result of strength exercises.2323 Pierson LM, Herbert WG, Norton HJ, et al. Effects of combined aerobic and resistance training versus aerobic training alone in cardiac rehabilitation. J Cardiopulm Rehabil. 2001;21(2):101-10. http://dx.doi.org/10.1097/00008483-200103000-00007. PMid:11314283.
http://dx.doi.org/10.1097/00008483-20010...
,2929 Arthur HM, Gunn E, Thorpe KE, et al. Effect of aerobic vs combined aerobic-strength training on 1-year, post-cardiac rehabilitation outcomes in women after a cardiac event. J Rehabil Med. 2007;39(9):730-5. http://dx.doi.org/10.2340/16501977-0122. PMid:17999012.
http://dx.doi.org/10.2340/16501977-0122...
Indeed, strength exercises provoke increases in the size of muscle fibers, with a consequent increase in the number of mitochondria, facilitating oxidative muscle activity.4949 Balakrishnan VS, Rao M, Menon V, et al. Resistance training increases muscle mitochondrial biogenesis in patients with chronic kidney disease. Clin J Am Soc Nephrol. 2010;5(6):996-1002. http://dx.doi.org/10.2215/CJN.09141209. PMid:20498251.
http://dx.doi.org/10.2215/CJN.09141209...
This is why it is important that future studies should investigate different physical training programs in relation to different outcomes among people who have suffered AMI.

We cannot fail to highlight the extensive search of the literature for scientific articles with high methodological quality and the best available evidence level. More than 4,000 studies were selected for systematic review and their titles and abstracts were read. To our knowledge this is the first meta-analysis to investigate the effects of different physical training modalities on the VO2peak of post-AMI patients.

CONCLUSIONS

Our data demonstrated that those participants who trained with the aerobic exercise modality obtained a significant increase in VO2peak. Additionally, this was the modality most used in the studies included in the meta-analysis. Combined exercise was not associated with a significant increase in VO2peak, but its use in cardiovascular rehabilitation programs is extremely important, since patients who suffer AMI do not only have reduced functional capacity, but also lose muscle strength and balance. It is therefore essential to encourage physical training programs for the post-AMI population, with appropriate control of exercise intensity and volume.

  • How to cite: Bourscheid G, Just KR, Costa RR, et al. Effect of different physical training modalities on peak oxygen consumptions in post-acute myocardial infarction patients: systematic review and meta-analysis. J Vasc Bras. 2021;20: e20210056. https://doi.org/10.1590/1677-5449.210056
  • Financial support: None.
  • The study was carried out at Faculdade Cenecista Santo Ângelo, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.

REFERÊNCIAS

  • 1
    Roth GA, Johnson C, Abajobir A, et al. Global, regional, and national burden of cardiovascular diseases for 10 causes, 1990 to 2015. J Am Coll Cardiol. 2017;70(1):1-25. http://dx.doi.org/10.1016/j.jacc.2017.04.052 PMid:28527533.
    » http://dx.doi.org/10.1016/j.jacc.2017.04.052
  • 2
    Martins WA, Rosa MLG, Matos RC, et al. Trends in mortality rates from cardiovascular disease and cancer between 2000 and 2015 in the most populous capital cities of the five regions of Brazil. Arq Bras Cardiol. 2020;114(2):199-206. PMid:32215484.
  • 3
    Oliveira GMM, Brant LCC, Polanczyk CA, et al. Estatística cardiovascular Brasil 2020. Arq Bras Cardiol. 2020;115(3):308-439. http://dx.doi.org/10.36660/abc.20200812
    » http://dx.doi.org/10.36660/abc.20200812
  • 4
    Ribeiro AL, Duncan BB, Brant LC, Lotufo PA, Mill JG, Barreto SM. Cardiovascular health in Brazil: trends and perspectives. Circulation. 2016;133(4):422-33. http://dx.doi.org/10.1161/CIRCULATIONAHA.114.008727 PMid:26811272.
    » http://dx.doi.org/10.1161/CIRCULATIONAHA.114.008727
  • 5
    Tibaut M, Mekis D, Petrovic D. Pathophysiology of myocardial infarction and acute management strategies. Cardiovasc Hematol Agents Med Chem. 2017;14(3):150-9. http://dx.doi.org/10.2174/1871525714666161216100553 PMid:27993119.
    » http://dx.doi.org/10.2174/1871525714666161216100553
  • 6
    Marcolino MS, Brant LCC, Araujo JG, et al. Implementation of the myocardial infarction system of care in city of Belo Horizonte, Brazil. Arq Bras Cardiol. 2013;100:307-14. PMid:23545995.
  • 7
    Bertuzzi M, Negri E, Tavani A, Vecchia C. Family history of ischemic heart disease and risk of acute myocardial infarction. Prev Med. 2003;37(3):183-7. http://dx.doi.org/10.1016/S0091-7435(03)00094-X PMid:12914823.
    » http://dx.doi.org/10.1016/S0091-7435(03)00094-X
  • 8
    Joshi NV, Toor I, Shah AS, et al. Systemic atherosclerotic inflammation following acute myocardial infarction: myocardial infarction begets myocardial infarction. J Am Heart Assoc. 2015;4(9):e001956. http://dx.doi.org/10.1161/JAHA.115.001956 PMid:26316523.
    » http://dx.doi.org/10.1161/JAHA.115.001956
  • 9
    Crea F, Liuzzo G. Pathogenesis of acute coronary syndromes. J Am Coll Cardiol. 2013;61(1):1-11. http://dx.doi.org/10.1016/j.jacc.2012.07.064 PMid:23158526.
    » http://dx.doi.org/10.1016/j.jacc.2012.07.064
  • 10
    Allahverdian S, Pannu PS, Francis GA. Contribution of monocyte-derived macrophages and smooth muscle cells to arterial foam cell formation. Cardiovasc Res. 2012;95(2):165-72. http://dx.doi.org/10.1093/cvr/cvs094 PMid:22345306.
    » http://dx.doi.org/10.1093/cvr/cvs094
  • 11
    Madsen EB, Gilpin E, Ahnve S, Henning H, Ross J Jr. Prediction of functional capacity and use of exercise testing for predicting risk after acute myocardial infarction. Am J Cardiol. 1985;56(13):839-45. http://dx.doi.org/10.1016/0002-9149(85)90766-0 PMid:2865888.
    » http://dx.doi.org/10.1016/0002-9149(85)90766-0
  • 12
    Kunz VC, Serra KBS, Borges ÉN, Serra PES, Silva E. Cardiopulmonary exercise testing in the early-phase of myocardial infarction. Rev Bras Fisioter. 2012;16(5):396-405. http://dx.doi.org/10.1590/S1413-35552012005000047 PMid:23032293.
    » http://dx.doi.org/10.1590/S1413-35552012005000047
  • 13
    Chiaranda G, Myers J, Arena R, et al. Improved percent-predicted peak VO(2) is associated with lower risk of hospitalization in patients with coronary heart disease. Analysis from the FRIEND registry. Int J Cardiol. 2020;310:138-44. http://dx.doi.org/10.1016/j.ijcard.2020.02.057 PMid:32139240.
    » http://dx.doi.org/10.1016/j.ijcard.2020.02.057
  • 14
    Siqueira CAS, Souza DLB. Reduction of mortality and predictions for acute myocardial infarction, stroke, and heart failure in Brazil until 2030. Sci Rep. 2020;10(1):17856.
  • 15
    Swank AM, Horton J, Fleg JL, et al. Modest increase in peak VO2 is related to better clinical outcomes in chronic heart failure patients: results from heart failure and a controlled trial to investigate outcomes of exercise training. Circ Heart Fail. 2012;5(5):579-85. http://dx.doi.org/10.1161/CIRCHEARTFAILURE.111.965186 PMid:22773109.
    » http://dx.doi.org/10.1161/CIRCHEARTFAILURE.111.965186
  • 16
    Kavanagh T, Mertens DJ, Hamm LF, et al. Prediction of long-term prognosis in 12 169 men referred for cardiac rehabilitation. Circulation. 2002;106(6):666-71. http://dx.doi.org/10.1161/01.CIR.0000024413.15949.ED PMid:12163425.
    » http://dx.doi.org/10.1161/01.CIR.0000024413.15949.ED
  • 17
    Kavanagh T, Mertens DJ, Hamm LF, et al. Peak oxygen intake and cardiac mortality in women referred for cardiac rehabilitation. J Am Coll Cardiol. 2003;42(12):2139-43. http://dx.doi.org/10.1016/j.jacc.2003.07.028 PMid:14680741.
    » http://dx.doi.org/10.1016/j.jacc.2003.07.028
  • 18
    Anderson L, Sharp GA, Norton RJ, et al. Home-based versus centre-based cardiac rehabilitation. Cochrane Database Syst Rev. 2017;6(6):CD007130. PMid:28665511.
  • 19
    Pelliccia A, Sharma S, Gati S, et al. 2020 ESC Guidelines on sports cardiology and exercise in patients with cardiovascular disease. Eur Heart J. 2021;42(2):17-96. PMid:32860412.
  • 20
    Leon AS, Franklin BA, Costa F, et al. Cardiac rehabilitation and secondary prevention of coronary heart disease: an American Heart Association scientific statement from the Council on Clinical Cardiology (Subcommittee on Exercise, Cardiac Rehabilitation, and Prevention) and the Council on Nutrition, Physical Activity, and Metabolism (Subcommittee on Physical Activity), in collaboration with the American association of Cardiovascular and Pulmonary Rehabilitation. Circulation. 2005;111(3):369-76. http://dx.doi.org/10.1161/01.CIR.0000151788.08740.5C PMid:15668354.
    » http://dx.doi.org/10.1161/01.CIR.0000151788.08740.5C
  • 21
    Carvalho T, Milani M, Ferraz AS, et al. Brazilian cardiovascular rehabilitation guideline - 2020. Arq Bras Cardiol. 2020;114(5):943-87. http://dx.doi.org/10.36660/abc.20200407 PMid:32491079.
    » http://dx.doi.org/10.36660/abc.20200407
  • 22
    Peixoto TC, Begot I, Bolzan DW, et al. Early exercise-based rehabilitation improves health-related quality of life and functional capacity after acute myocardial infarction: a randomized controlled trial. Can J Cardiol. 2015;31(3):308-13. http://dx.doi.org/10.1016/j.cjca.2014.11.014 PMid:25633911.
    » http://dx.doi.org/10.1016/j.cjca.2014.11.014
  • 23
    Pierson LM, Herbert WG, Norton HJ, et al. Effects of combined aerobic and resistance training versus aerobic training alone in cardiac rehabilitation. J Cardiopulm Rehabil. 2001;21(2):101-10. http://dx.doi.org/10.1097/00008483-200103000-00007 PMid:11314283.
    » http://dx.doi.org/10.1097/00008483-200103000-00007
  • 24
    Meka N, Katragadda S, Cherian B, Arora RR. Endurance exercise and resistance training in cardiovascular disease. Ther Adv Cardiovasc Dis. 2008;2(2):115-21. http://dx.doi.org/10.1177/1753944708089701 PMid:19124415.
    » http://dx.doi.org/10.1177/1753944708089701
  • 25
    Higgins JPT, Deeks JJ, Altman DG. Cochrane handbook for systematic reviews of interventions, version 5.1. Oxford: Cochrane Collaboration; 2011.
  • 26
    Moher D, Liberati A, Tetzlaff J, Altman DG. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA Statement. Open Med. 2009;3(3):e123-30. PMid:21603045.
  • 27
    Higgins JP, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-analyses. BMJ. 2003;327(7414):557-60. http://dx.doi.org/10.1136/bmj.327.7414.557 PMid:12958120.
    » http://dx.doi.org/10.1136/bmj.327.7414.557
  • 28
    Takagi S, Murase N, Kime R, Niwayama M, Osada T, Katsumura T. Aerobic training enhances muscle deoxygenation in early post-myocardial infarction. Eur J Appl Physiol. 2016;116(4):673-85. http://dx.doi.org/10.1007/s00421-016-3326-x PMid:26759155.
    » http://dx.doi.org/10.1007/s00421-016-3326-x
  • 29
    Arthur HM, Gunn E, Thorpe KE, et al. Effect of aerobic vs combined aerobic-strength training on 1-year, post-cardiac rehabilitation outcomes in women after a cardiac event. J Rehabil Med. 2007;39(9):730-5. http://dx.doi.org/10.2340/16501977-0122 PMid:17999012.
    » http://dx.doi.org/10.2340/16501977-0122
  • 30
    Benetti M, Araujo CL, Santos RZ. Cardiorespiratory fitness and quality of life at different exercise intensities after myocardial infarction. Arq Bras Cardiol. 2010;95(3):399-404. http://dx.doi.org/10.1590/S0066-782X2010005000089 PMid:20640381.
    » http://dx.doi.org/10.1590/S0066-782X2010005000089
  • 31
    Khalid Z, Farheen H, Tariq MI, Amjad I. Effectiveness of resistance interval training versus aerobic interval training on peak oxygen uptake in patients with myocardial infarction. J Pak Med Assoc. 2019;69(8):1194-8. PMid:31431779.
  • 32
    Santi GLD, Moreira HT, Carvalho EEV, et al. Influence of aerobic training on the mechanics of ventricular contraction after acute myocardial infarction: a pilot study. Arq Bras Cardiol. 2018;110(4):383-7. http://dx.doi.org/10.5935/abc.20180049 PMid:29791580.
    » http://dx.doi.org/10.5935/abc.20180049
  • 33
    Oliveira NL, Ribeiro F, Teixeira M, et al. Effect of 8-week exercise-based cardiac rehabilitation on cardiac autonomic function: a randomized controlled trial in myocardial infarction patients. Am Heart J. 2014;167(5):753-61. http://dx.doi.org/10.1016/j.ahj.2014.02.001 PMid:24766987.
    » http://dx.doi.org/10.1016/j.ahj.2014.02.001
  • 34
    Trachsel LD, David LP, Gayda M, et al. The impact of high-intensity interval training on ventricular remodeling in patients with a recent acute myocardial infarction - a randomized training intervention pilot study. Clin Cardiol. 2019;42(12):1222-31. http://dx.doi.org/10.1002/clc.23277
    » http://dx.doi.org/10.1002/clc.23277
  • 35
    Moholdt T, Aamot IL, Granøien I, et al. Aerobic interval training increases peak oxygen uptake more than usual care exercise training in myocardial infarction patients: a randomized controlled study. Clin Rehabil. 2012;26(1):33-44. http://dx.doi.org/10.1177/0269215511405229 PMid:21937520.
    » http://dx.doi.org/10.1177/0269215511405229
  • 36
    Iorga A, Cunningham CM, Moazeni S, Ruffenach G, Umar S, Eghbali M. The protective role of estrogen and estrogen receptors in cardiovascular disease and the controversial use of estrogen therapy. Biol Sex Differ. 2017;8(1):33. http://dx.doi.org/10.1186/s13293-017-0152-8 PMid:29065927.
    » http://dx.doi.org/10.1186/s13293-017-0152-8
  • 37
    Franzoni L, Stein R. Moderate exercise improves depressive symptoms and pain in elderly people. Int J Cardiovasc Sci. 2019;32(6):563-4.
  • 38
    Stein R, Franzoni LT. Digital tools and cardiovascular rehabilitation. Int J Cardiovasc Sci. 2018;31(6):558-9.
  • 39
    Liu JX, Zhu L, Li PJ, Li N, Xu YB. Effectiveness of high-intensity interval training on glycemic control and cardiorespiratory fitness in patients with type 2 diabetes: a systematic review and meta-analysis. Aging Clin Exp Res. 2019;31(5):575-93. http://dx.doi.org/10.1007/s40520-018-1012-z PMid:30097811.
    » http://dx.doi.org/10.1007/s40520-018-1012-z
  • 40
    Li J, Li Y, Atakan MM. The molecular adaptive responses of skeletal muscle to high-intensity exercise/training and hypoxia. Antioxidants. 2020;9(8):656.
  • 41
    Menshikova EV, Ritov VB, Fairfull L, Ferrell RE, Kelley DE, Goodpaster BH. Effects of exercise on mitochondrial content and function in aging human skeletal muscle. J Gerontol A Biol Sci Med Sci. 2006;61(6):534-40. http://dx.doi.org/10.1093/gerona/61.6.534 PMid:16799133.
    » http://dx.doi.org/10.1093/gerona/61.6.534
  • 42
    Distefano G, Goodpaster BH. Effects of exercise and aging on skeletal muscle. Cold Spring Harb Perspect Med. 2018;8(3):a029785. http://dx.doi.org/10.1101/cshperspect.a029785 PMid:28432116.
    » http://dx.doi.org/10.1101/cshperspect.a029785
  • 43
    Clark JE. The impact of duration on effectiveness of exercise, the implication for periodization of training and goal setting for individuals who are overfat, a meta-analysis. Biol Sport. 2016;33(4):309-33. http://dx.doi.org/10.5604/20831862.1212974 PMid:28090136.
    » http://dx.doi.org/10.5604/20831862.1212974
  • 44
    Detry JM, Rousseau M, Vandenbroucke G, Kusumi F, Brasseur LA, Bruce RA. Increased arteriovenous oxygen difference after physical training in coronary heart disease. Circulation. 1971;44(1):109-18. http://dx.doi.org/10.1161/01.CIR.44.1.109 PMid:5561413.
    » http://dx.doi.org/10.1161/01.CIR.44.1.109
  • 45
    Di Francesco Marino S, Sciartilli A, Di Valerio V, Di Baldassarre A, Gallina S. The effect of physical exercise on endothelial function. Sports Med. 2009;39(10):797-812. http://dx.doi.org/10.2165/11317750-000000000-00000 PMid:19757859.
    » http://dx.doi.org/10.2165/11317750-000000000-00000
  • 46
    Garcia EL, Menezes MG, Stefani CM, Danzmann LC, Torres MA. Ergospirometry and echocardiography in early stage of heart failure with preserved ejection fraction and in healthy individuals. Arq Bras Cardiol. 2015;105(3):248-55. PMid:26247247.
  • 47
    Arena R, Sietsema KE. Cardiopulmonary exercise testing in the clinical evaluation of patients with heart and lung disease. Circulation. 2011;123(6):668-80. http://dx.doi.org/10.1161/CIRCULATIONAHA.109.914788 PMid:21321183.
    » http://dx.doi.org/10.1161/CIRCULATIONAHA.109.914788
  • 48
    Belli KC, Silva PFD, Franzoni LT, Myers J, Stein R, Ribeiro JP. Speed and grade increment during cardiopulmonary treadmill testing: impact on exercise prescription. Int J Cardiovasc Sci. 2019;32:374-83. http://dx.doi.org/10.5935/2359-4802.20190058
    » http://dx.doi.org/10.5935/2359-4802.20190058
  • 49
    Balakrishnan VS, Rao M, Menon V, et al. Resistance training increases muscle mitochondrial biogenesis in patients with chronic kidney disease. Clin J Am Soc Nephrol. 2010;5(6):996-1002. http://dx.doi.org/10.2215/CJN.09141209 PMid:20498251.
    » http://dx.doi.org/10.2215/CJN.09141209

Publication Dates

  • Publication in this collection
    06 Aug 2021
  • Date of issue
    2021

History

  • Received
    08 Apr 2021
  • Accepted
    08 May 2021
Sociedade Brasileira de Angiologia e de Cirurgia Vascular (SBACV) Rua Estela, 515, bloco E, conj. 21, Vila Mariana, CEP04011-002 - São Paulo, SP, Tel.: (11) 5084.3482 / 5084.2853 - Porto Alegre - RS - Brazil
E-mail: secretaria@sbacv.org.br