Efectos del HIIT frente a MICT sobre la función cardiorrespiratoria y metabólica en poblaciones clínicas: revisión sistemática y metaanálisis

Introduction: Structured physical training is a key tool in the prevention of cardiometabolic diseases. Two commonly used methods HIIT (high-intensity interval training) and MICT (moderate-intensity continuous training) have shown benefits, but their comparative effectiveness remains under investigation. Objective: To compare the effects of HIIT versus MICT on VO₂max, blood pressure, and lipid profile in individuals at cardiovascular and metabolic risk, considering their applicability in various clinical populations. Methods: A systematic search was conducted in five databases. Eight randomized controlled trials were included (n = 242). Risk of bias (RoB 2) and certainty of evidence (GRADE) were assessed. Fixed-effects models were applied. Results: HIIT showed greater effectiveness than MICT across all variables. VO₂max improved by +1.57 ml/kg/min (95% CI: 1.02–2.12; p<0.001). Systolic blood pressure decreased by −4.30 mmHg and diastolic by −2.60 mmHg. Lipid profile improved: total cholesterol −6.70 mg/dL, LDL −6.60 mg/dL, triglycerides −8.70 mg/dL, and HDL +2.90 mg/dL. Heterogeneity was low (I² < 35%), and the certainty of evidence was high. Conclusions: HIIT is more effective than MICT in improving cardiovascular and metabolic health, with consistent effects across different ages and clinical conditions.