The lack of energy and muscle trembling may be due to low blood sugar, cold, electrolyte disorders, hypothyroidism, anxiety disorders, Parkinson’s disease and other reasons. 1. Hypoglycemia: low glucose level in the blood leads to insufficient energy supply to the tissue cells, so the body will be weak and reflexively stimulate the sympathetic nerves leading to muscle shaking. 2. Cold: Virus invasion of the body induces a systemic tissue inflammatory response, muscle mass anaerobic respiration and the emergence of this symptom. 3. Electrolyte disorders: Hypokalemia, hypercalcemia, etc. lead to a decrease in nerve excitability, so this symptom appears. 4. Hypothyroidism: the thyroid gland synthesizes and secretes less thyroid hormone, leading to low basal metabolic rate of the whole body, so this symptom appears. 5. Anxiety disorders: not only mental disorders such as nervousness, anxiety and depression, but also physical symptoms such as panic, fatigue, drowsiness and muscle trembling. 6. Parkinson’s disease: apoptosis of dopaminergic neurons in the substantia nigra striata and other parts of the brain leads to the emergence of static tremor, dyskinesia and other symptoms. The lack of energy and muscle shaking may be related to a variety of factors, it is recommended to consult a doctor for a clear diagnosis.