Exercise is known to have stress-busting benefits. Physical activity boosts the production of the brain's feel-good neurotransmitters known as endorphins.

In one study, researchers found that exercise can also help improve memory problems related to stress in breast cancer survivors.

Findings of a new research, however, revealed that while exercise can help relieve stress and is generally beneficial to physical health, doing heavy exercise may not be a good idea when you are emotionally upset.

Researchers found that doing hard workouts when you are angry can increase the risk for potentially deadly heart attack.

In a large international study published in the journal Circulation on Oct. 11, researchers found that feeling intense anger while working out was associated with more than threefold increased risk for heart attack within the hour.

Study researcher Andrew Smyth, from McMaster University in Canada, and colleagues also looked at emotional stress and exercise individually to see if each of these factors would influence heart attack risk on their own. They discovered that emotional stress alone or exercise alone can more than double a person's likelihood of having a heart attack within the hour.

"We explored the triggering association of acute physical activity and anger or emotional upset with acute myocardial infarction to quantify the importance of these potential triggers in a large, international population," Smyth and colleagues wrote in their study.

"Physical exertion and anger or emotional upset are triggers associated with first AMI in all regions of the world, in men and women, and in all age groups, with no significant effect modifiers."

Smyth explained that extreme physical and emotional triggers are believed to have similar effects on the body.

Both, for instance, increase heart rate and blood pressure, which can alter the flow of blood in blood vessels and reduce blood supply to the heart. The risk is particularly more concerning in those whose blood vessels are already narrowed by plaque that can block blood flow and lead to a heart attack.

Based on their findings, the researchers recommended that those who are upset or angry who want to blow off steam by exercising to not go beyond their normal routine of physical activity.

Barry Jacobs, from the American Heart Association who was not involved in the study, said that other than going for heavy exercise, there are several ways people can deal with their emotions such as through breathing and relaxation exercises as well as anger management programs and meditation.