I'm afraid to be very active because it's well known that if you exercise too much your body produces coritsol which increases blood sugar and blood pressure. I've read that if you are in the gym for more hour your body will produce cortisol. What, does a timer start when you walk through the gym door? Because of this information I tend to favor being moderately active. But I need to lose weight. How long can I work out in the gym before I quit. If I work out more than once a day is that a problem? Is this worth worrying about??