Knee muscle throbbing may be caused by localized overexertion, cold knees or calcium deficiency. 1. Overexertion: If the muscles are overworked by prolonged exercise, the muscles around the knee may continue to spasm, resulting in a throbbing condition. Once the muscle fatigue is relieved, the throbbing will usually resolve. 2. Cold knee: If the knee is cold, it may cause the muscles around it to spasm, which will lead to the symptoms of muscle throbbing. 3. Calcium deficiency: If the knee muscles are deficient in calcium, it will lead to higher excitability, which will result in muscle throbbing. If the knee muscle throbbing occurs occasionally, you can rest, local hot compresses and other ways to relieve the symptoms. If the knee muscle is often jumping, we should promptly go to the hospital for examination and targeted treatment.