"Running water is never stale and a door-hinge never gets worm-eaten." Physical labor and moderate physical training promote the circulation of qi and blood, improve appetite, enhance physique and are the essential conditions of human existence and preserving good health. However, overlong physical labor or physical training, overburden and ignorance of proper rest may exceed the endurance of the organism. As time passes, these factors may make healthy people break down from constant overwork and the patients' diseases worsened. For instance, though the patients with various maims and chronic diseases are badly in need of participation in the physical labor and physical training in their power, they are susceptible to the exacerbation or deterioration of the diseases due to physical overstrain of physique, for these patients generally have poorer endurance of physical labor and training than healthy people. For example, the patients with coronary heart disease and myocarditis themselves have different degrees of muscular ischemia and muscular hypoxia. If they do not limit the amount and duration of their physical labor or physical training to cause overfatigue, this may induce angina pectoris, heart failure, even give rise to sudden death due to overburden of the heart. Take diabetics for another example. The physical overstrain during the treatment is extremely susceptible to hypoglycemic reaction.
The following points should be paid attention to in order that the patients can not only persevere in physical labor or physical training but also avoid physical overstrain. Firstly, the amount of physical labor or physical training should be strictly followed under the guidance of the doctor. Physical labor or physical training should proceed in an orderly way and step by step, from small amount to large amount. Secondly, the types, time, intensity, etc. of physical labor or training should be scientifically selected under the guidance of the medical and nursing staff. It is the best to combine the scientific nature with interesting nature in selecting the types of physical labor or physical training; it is the best to arrange the time in the early morning or one to two hours after the breakfast; the intensity of physical training is always determined by warmth, mild sweating as well as relaxation, comfort, good appetite and sound sleep after the training. Thirdly, the abnormal sensations during the physical labor or training should be instantly reported to the medical and nursing staff such as headache, dizziness, palpitation, declined appetite and poor sleep so as to be noticed. Regular physical examination is conducted to revise the training plan whenever necessary in accordance with the patient's conditions.