The 5-20-30 method includes five rounds of intervals of 30 seconds low-intensity, 20 seconds moderate, and 5 seconds high-intensity exercise. Gastrointestinal surgeon Dr KK Kursiwal said this high-intensity interval training strategy is designed to "maximise fat burning". "The problem with belly fat is that it's not limited to the skin but also surrounds internal organs," Dr Kursiwal added.