Exercising is good for one's health, but in excess it can be harmful. A recent research report from Australia claims that exercising for more than four hours a day can force intestinal bacteria to leak into the stream of blood, resulting in poisoning.

The researchers from the Monash University in Australia said the study, which was published in the International Journal of Sports Medicine, was based on their observation of the people participating in a range of strenuous events.

The team monitored the blood samples of the subject population just before and after they had participated in the events.

“Blood samples taken before and after the events, compared with a control group, proved that exercise over a prolonged period of time causes the gut wall to change, allowing the naturally present bacteria, known as endotoxins, in the gut to leak into the bloodstream," confirmed lead researcher Ricardo Costa, in a statement.

According to the study team, the leakage of the endotoxins into the bloodstream elicits an immune response. The resultant systemic inflammatory response is then treated as a serious case of infection.

The Times of India reports that sometimes the intensified immune response may even lead to the systemic inflammatory response syndrome, induces by the sepsis. If not diagnosed or treated on time, it may even prove fatal to the concerned individual.

"Nearly all of the participants in our study had blood markers identical to patients admitted to hospital with sepsis," Costa explained. "That's because the bacterial endotoxins that leach into the blood as a result of extreme exercise, triggers the body's immune cells into action."

Costa further suggests people get a health check before participating in an activity that requires “peak endurance.” In addition, the researcher has recommended people to start up with a training program that is slow paced before actually participating in strenuous activity.