Whether or not holding your breath is harmful to your body depends mainly on the length of time you hold your breath. Short-term breath holding or appropriate breath holding, will not cause harm to the body, if a long time to hold the breath, then it will lead to the brain, heart muscle and other lack of oxygen. Proper breath holding has certain benefits for the human body, can increase personal lung capacity, but also can enhance lung function, exercise the human heart. But if you hold your breath for too long, more than the body’s ability to withstand, will cause the brain, myocardial hypoxia or other organs ischemia and hypoxia, easily lead to dizziness, chest pain, coma and other symptoms, and even serious cases will cause breathlessness fainting. When exercising lung capacity, pay attention to the time of breath holding, should not be excessive. Ordinary people hold their breath for about 3 to 4 minutes, and for patients with poor lung function, they can practice holding their breath appropriately. Before holding your breath, take a deep breath and relax, if you feel any discomfort during the process of holding your breath, stop immediately and do not have to force yourself.