The so-called law of the world is to change one's destiny by the law of causality, the law that good is rewarded with good and evil with evil, as the Buddha said, so that the world can get good results. If the purpose of learning Buddhism is secular law, then there is no contradiction between fitness and learning Buddhism. Of course, in Buddhism, there are actually good ways to achieve the purpose of fitness, such as worshipping Buddha, especially worshipping Buddha. Many people who study Buddhism, especially women, actively use Buddha worship to keep fit, so they can quit their studies. Why not?
If you are studying Buddhism and worldly law, it is important to persevere and give up who I am. It is better not to exercise, but to cultivate your mind with kung fu.