High-intensity interval training (HIIT) workouts differ from traditional cardio primarily in their structure and intensity. HIIT involves short bursts of intense exercise followed by rest or low-intensity periods, leading to improved metabolic rate and greater calorie burn post-workout. In contrast, traditional cardio focuses on steady-state exercise over longer durations. While both methods improve cardiovascular health, HIIT can enhance muscle conditioning and efficiency in a shorter time, making it appealing for those with limited schedules.