The Effectiveness of Exercise in Reducing Cardiovascular Risk Factors Among Adults: A Systematic Review and Meta-Analysis

Cardiovascular disease (CVD) remains one of the major causes of sickness and death in the world. However, lifestyle modifications, such as exercise, can significantly reduce the risk of this disease. This study aimed to assess the effectiveness of various forms of physical activity in reducing CVD risk factors among adults. A comprehensive search of the databases PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Central Register of Controlled Trials (CENTRAL), and Excerpta Medica Database (EMBASE) databases was conducted between January 1, 2014, and May 31, 2024, as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Randomized controlled trials (RCTs), cohort studies, and observational studies on the impact of aerobic, resistance, or combined training on cardiovascular risk factors in adults (≥18 years) were considered for inclusion. Data relating to primary outcomes, including stroke and myocardial infarction rates, BP, cholesterol levels, and BMI were collected. The Cochrane risk-of-bias tool and the Methodological Index for Non-Randomized Studies (MINORS) checklist were used for quality and bias assessment. Meta-analyses were performed using the RevMan software, with heterogeneity evaluated by I² statistics; 17 studies, including 11 RCTs and six cohort studies, met the inclusion criteria. There was a significant reduction in the mean systolic BP (SBP) by 3.32 mmHg [95% confidence interval (CI): 0.85-5.78 mmHg; p<0.0001] and mean diastolic BP (DBP) by 2.99 mmHg (95% CI: 2.34-3.64 mmHg; p < 0.00001) after exercise interventions. Moreover, cholesterol levels and BMI values improved with exercise. Those who exercised had a lower risk of stroke or heart attack compared with the controls [odds ratio (OR): 0.57; 95% CI: 0.28-1.14; p >0.0001], although there was substantial heterogeneity in effect size across the studies (I² = 98%). Different types of physical activity (i.e., aerobic, resistance, or combined exercise) can effectively reduce key cardiovascular risk factors, including BP, cholesterol levels, and BMI values. Regular physical activity is still regarded as the most effective preventive measure against CVD, despite inconsistencies in research findings. Future studies should aim to identify optimal exercise programs and their long-term effects on diverse populations.