An effective form of cardio for burning calories includes high-intensity interval training (HIIT). This method alternates between short bursts of intense activity and brief recovery periods, maximizing calorie burn in a shorter time frame compared to steady-state workouts. HIIT can be performed using various exercises, such as sprinting, cycling, or bodyweight movements. The intensity not only boosts calorie expenditure during the workout but also elevates the resting metabolic rate, promoting further calorie burning post-exercise. Overall, incorporating HIIT into fitness routines can provide efficient cardiovascular workouts while enhancing endurance and strength.