The whole field of yoga baised on this philosophy. Physical aspects of yoga are not the main objective. It's just considered necessary to have healthy body for healthy mind. The second stage of having clear understanding of your mind ( mostly emotional aspects) takes decade of practice. Only after that you reach the state where you can begin to have control over your emotions and instead of being slave to your environment you can make choose how you want to feel ( example being burning monk) . Some people claim (no empirical evidence) that fully trained yogi can put themselves into deep sleep ( hibernation) for multiple years.