The most effective way to burn calories at rest involves increasing your resting metabolic rate (RMR) through building muscle mass. Muscles consume more energy than fat, even at rest. Engaging in regular strength training and maintaining a physically active lifestyle can elevate your RMR. Additionally, ensuring a balanced diet rich in protein can further support muscle synthesis. Incorporating high-intensity interval training (HIIT) may also contribute to a higher post-exercise oxygen consumption, which aids in burning extra calories afterwards.