Good question. I just did a search and found something interesting:
If you have breathing problems or problems with high blood pressure, you should consult a doctor before lifting. You have to hold your breath in order to get tighter and lift more weight. By holding your breath, you will increase your blood pressure, which is why you need to be careful.
Last edited by Chefboiali; 12-10-2006 at 06:31 PM.