Moderate exercise is not strenuous enough to curb heart disease, according to a recent study.

The study, based out of Queen’s University in Belfast, Northern Ireland, indicated that middle-aged men must exercise vigorously to delay death by cardiovascular disease. Of the 2,000 men in the study, those who exercised vigorously were less likely to die an untimely death from heart disease.

Some University of Wisconsin professors question the study’s validity, however.

Exercise and physiology professor Ann Ward said that there are significant health benefits to moderate exercise, especially for women.

“Many more studies show that moderate exercise does decrease the risk,” Ward said. “This is only one out of 40 to 50 studies.”

Current U.S. and UK guidelines for heart disease prevention recommend 30 minutes of moderate exercise five days per week.

Kinesiology professor Bill Morgan, director of UW-Madison’s Exercise Psychology Laboratory, said there is a big debate over how intense a workout has to be in order to reap health benefits.

He said the most important aspect of exercise is how long someone sticks with it, rather than how strenuous it is. Benefits like deeper sleep, weight loss and improved mood take time to develop, he said.

Morgan’s study of 30 years of data indicated that half of the people who pick up exercise quit after several months, and only 25 percent of people still exercised one year after they started.

“Most people quit by the time they would get the benefits,” Morgan said.

He said the best way to stick with a new workout is to pick one that is enjoyable and purposeful, no matter the intensity of the workout.

Kinesiology professor Ron Carda also said workouts must be tailored to an individual’s preferences.

“Good research shows that a preferred exertion is what they will stick with,” Carda said. “The bottom line is that a lot of individuality goes into any program, based on whether you challenge yourself and how skilled you are with an activity.”

He said current exercise regimens are starting to get away from machines because people lose motivation to come back to a machine for exercise every day.

Morgan said it is difficult to prescribe workout regimens based on flat presumptions for the average person because exercise is a relatively new science.

“Back into the mid 30s, farmers would start work at five or six a.m. and were physically active all the time,” Morgan said. “It’s only been the last few centuries that we have become so sedentary.”

The Queen’s University study followed 1,975 healthy men aged 45 to 59 for 11 years. During the study, 252 men died, 75 percent of them from heart disease. The researchers found that the likelihood of death increased the most in men who were less active. Those with the highest levels of intense exercise, burning 52 calories per day, were 47 percent less likely to die early and 62 percent less likely to die of heart disease.

Burning 54 calories is equivalent to approximately nine minutes of jogging.