First of all, the essence of "not letting go of the old" may be everyone's ideological spirit, but it refers more to our spirit. The older people get, the worse their spirits get. This is also the so-called "residual essence", which means that what you want to do can't be done. In fact, for many people, this is understandable. When I was a child, even today, I was too tired to move. Get up the next morning and get active immediately. This is the resilience of young people. Old people are completely different. If you are overworked, you may not recover for a few days.
Of course, it is reasonable to explain this sentence from the perspective of husband and wife's sexual life. The older you get, the greater the interval between husband and wife's sexual life. Therefore, it is difficult for the elderly to recover their physical fitness. Don't eat less fierce fire. Fire refers to the "Yang Qi" of the human body, usually called kidney yang.
When you are young, you shouldn't eat too much healthy things. It is not only useless, but also harmful to our health. As the old saying goes, we often experience this kind of thing in our life, such as some tonic things, such as old dog meat, poisonous snakes and so on. Many young people eat too much, and when they are dry and hot, they often have nosebleeds and feel uncomfortable. This is the origin of "eat less and don't eat strong fire"