At its core, HIIT involves alternating between high-intensity intervals—typically reaching at least 80% of one's maximum heart rate—and lower-intensity movements. This cycle creates a metabolic demand that forces the body to adapt rapidly. Scientific studies have shown that just 30 minutes of HIIT per week can lead to improved glucose control and mitochondrial activity. Furthermore, the "afterburn" effect, or excess post-exercise oxygen consumption (EPOC), ensures that the body continues to burn calories long after the session has ended. Flexibility and Accessibility
One of the primary advantages of HIIT is its extreme versatility. Workouts can be adapted for any fitness level and performed almost anywhere. Common structures include: Adaptations to Endurance and Strength Training - PMC SM - HIIT Workouts.zip
Granata and colleagues (Granata et al. 2016b) showed that mitochondrial respiration and citrate synthase (CS) activity increased ( National Institutes of Health (.gov) the "afterburn" effect