1, poor mental state. For example, if you are too nervous or too excited, you will be afraid when you see others being hurt or bleeding.

2. Gravity impact. Syncope caused by a sudden stop after a sprint.

3. Increased chest and lung pressure. It often happens when weightlifters do heavy clean and jerk.

4. Orthostatic blood pressure is too low. You can rule this out.

5. Cardiogenic syncope. Narrow coronary arteries can't meet the needs of myocardial blood supply, and if they are middle-aged and elderly friends, the chances will be even greater.

6, heatstroke. This is almost impossible. The air conditioner in the gym should be large enough to prevent customers from heatstroke.

If you don't see that other people's injuries are useless for weightlifting, then the most likely reasons are 2 and 5.