There are four main clinical manifestations of poor physical fitness, including the manifestations of the digestive system, the manifestations of the nervous system, the manifestations of the respiratory system and the manifestations of the circulatory system. First, the digestive manifestations of poor health are digestive system absorption and digestive disorders, indigestion, nausea, vomiting, abdominal distension, loss of appetite, aversion to grease, bloating, diarrhea, alternating diarrhea and constipation are the digestive manifestations of poor health. Second, the circulatory system manifestations of poor health are chest tightness, shortness of breath, palpitations, precordial discomfort after exertion and spontaneous precordial pain after mild exercise, all of which are clinical manifestations of poor health, diminished cardiopulmonary function and reduced lung capacity. Third, respiratory system manifestations include susceptibility to respiratory diseases, such as susceptibility to infectious colds, upper respiratory tract infections, and tonsillitis are all manifestations of poor physical fitness. Fourth, the performance of the nervous system, such as insomnia, forgetfulness, dreaminess, etc. are all signs of poor health.