Exercise is risky, so exercise should be cautious. On the surface, sudden death by sports seems to be silent and hard to prevent, but it can actually be found. Body voice is the most honest. You should feel your own voice. If the body protests, you should give up when it is time to give up. Although sudden death by sports occurs suddenly and quietly, it does not mean that there is no sign of sudden death. Finding these dangerous signs in time and stopping exercise are the most effective ways to prevent sudden death. When the following symptoms appear during exercise: dizziness, palpitation, chest pain, chest tightness, shortness of breath, nausea, dysphagia and general weakness, it means that the body can no longer eat and has begun to protest. At this time, you should stop exercising and have a rest. Don't bite the bullet and stick to it.