When Julie Stoltman began working out, she lost weight and felt better about herself.

But this made her push further – exercising twice per day, every day, to the point of exhaustion.

“I felt like I had to. It’s just messed up,” Stoltman said. “You can’t maintain it. Your body just can’t keep up.”

Stoltman is addicted to exercising. Although she now works out about half as often as she did, she said, she still feels pain in her hips and knees.

While she works on managing her addiction, a recent study suggests it could be more difficult than expected. In fact, exercise could be as addictive as drugs, according to research at the University of Wisconsin-Madison.

The study used two groups of 24 mice. The mice ran on wheels for six days straight, stopping only for food, water and sleep. On the seventh day, researchers kept the mice from exercising and then tested their brains.

The tests showed neuronal surges in the brain when the mice were not exercising, similar to those of cocaine cravings in human drug addicts.

One of the study’s researchers, Stephen Gammie, professor in Madison’s zoology department, said the study shows further complexities in addictive behavior.

J. Clark Laundergan, director of the Center for Addiction Studies at the University’s Duluth campus, said addictions are complex. He said an addiction is usually a combination of how a person behaves and the way he or she responds to it.

Laundergan said people can easily become hooked on something that satisfies them.

However, he said, this does not typically become a problem until it interferes with their health or social relationships.

Arthur Leon, a University kinesiology professor, said he does not think exercise addictions would be bad.

“I would hope more people would be addicted to exercise,” Leon said.

Leon said more exercise is good because it reduces chances of stroke, obesity and hypertension.

While exercise is healthy, some experts say, it is important to keep a balanced lifestyle.

“Everything in moderation is good, and anything in excess is trouble,” said Don Dengel, a University kinesiology professor.

Dengel said the brain responds to endorphins released by pleasurable activities such as exercise, but these endorphins can be addictive.

He also said exercising continuously is bad because a body needs downtime. If a body is not given downtime from exercise, its muscles, bones and immune system could be damaged. Also, injuries are more likely to occur.

According to American College of Sports Medicine exercise guidelines, people should work out three to five times per week for 30-45 minutes each session.

Dengel said higher intensity or frequency than that does not improve a person’s health.

If a student becomes addicted to exercise, Dave Golden, public health director of Boynton Health Service, said he or she should go to Boynton’s mental health clinic.

At the clinic an addicted student will see a counselor. From there, the counselor directs him or her where to go next.

Golden said they see people addicted to many things, and these addictions are not easily treated. Most students who have an addiction get therapy, he said.