Soreness of the waist and knees (a feeling of soreness and weakness of the waist and knees) and fatigue can be attributed to a weak kidney qi syndrome, which can be regulated by orally taking Chinese herbal soup with the addition or subtraction of Dazhongyuan Decoction. Soreness and weakness of the waist and knees, and fatigue of the body are considered by Chinese medicine practitioners to be a sign of weakness of kidney qi. Kidney is the main bone, waist is the capital of kidney, if kidney qi is weak, then waist and knee are sore and painful; if kidney qi is weak, it cannot drum up the spirit, resulting in spiritual fatigue and weakness (mental exhaustion and physical weakness). In addition, weak kidney qi, the inability to run qi and blood, blood is not full, can also be manifested as a thin white face; weak kidney qi, fixed (consolidation) failure, manifested as nocturnal urination, frequent urination, long and so on. Treatment should benefit the qi and tonify the kidneys, and may be given as Dajianyuan Decoction with additional subtractions. In the formula, ginseng, Chinese yam, roasted licorice benefit the qi and strengthen the kidney; eucommia, cornelian cherry warms and nourishes the kidney qi; ripened dihuang, wolfberry, angelica replenishes the essence and blood; if the fatigue is very serious, add astragalus to replenish the middle and benefit the qi (treating the qi deficiency by replenishing the spleen), and so on. If you have any symptoms such as aching waist and knees, fatigue, etc., it is recommended that you consult a professional physician for standardized treatment under the physician’s diagnosis and treatment, and do not take medication on your own in order to avoid delaying your condition.