Exercise is good for you — there's no debate over that. But there are questions about whether there's a point at which excessive exercise could become bad for you. Some advice:

Go: People who exercise regularly live an average of seven years longer than people who are inactive.

Stop: Exercise addiction is as real as drug addiction, Psychology Today says, and when an addict misses a workout session, the withdrawal symptoms are similar, including shaking.

Go: The American Heart Association and the American College of Sports Medicine call for a minimum of 150 minutes a week of moderate exercise or 75 minutes of strenuous exercise.

Stop: The gains from exercising taper off the longer a person exercises. The first half-hour provides the greatest benefits. In a study by the National Institutes of Health, the benefits flattened out after one hour of strenuous exercise a day.

Go: Exercise has been proven to have several effects that lower the risk of heart trouble, including lowering blood pressure, increasing "good" cholesterol and decreasing "bad" cholesterol.

Stop: It's not just your heart that's at risk. Joints and muscles are subject to overuse and repetitive stress injuries.

Jeff Strickler