There's some debate in the fitness world about the effectiveness of what is known as “intense cardio,” a high-energy, fat-burning exercise regimen.
Its advocates praise it as a way to quickly burn hundreds of calories. At least one health researcher, however, is not convinced.
Writing in the Canadian Journal of Cardiology, he warns that high levels of intense exercise may be “cardiotoxic.” That, he says, can lead to permanent structural changes in the heart, which can, in some individuals, predispose them to experience arrhythmias.
But Dr. André La Gerche, Head of Sports Cardiology at the Baker IDI Heart and Diabetes Institute in Melbourne, Australia, wants to make it clear that he is talking about a matter of degree.
Possible adverse health effects
"Much of the discussion regarding the relative risks and benefits of long-term endurance sports training is hijacked by definitive media-grabbing statements, which has fueled an environment in which one may be criticized for even questioning the benefits of exercise," La Gerche said in a statement. "This paper discusses the often questionable, incomplete, and controversial science behind the emerging concern that high levels of intense exercise may be associated with some adverse health effects."
There has been plenty of research that points to walking as an effective health and weight-maintenance strategy. But because it isn't as strenuous as a lot of other exercises, walking needs to be done on a regular basis, and for a lot longer than an intense workout to achieve the same results.
Fortunately, most of us walk as part of our normal daily lives. If we can work in about 30 minutes of brisk walking a day, the American Heart Association says, we can produce a number of healthy benefits.
For example, the Heart Association cites research showing a half-hour of walking each day can reduce the risk of coronary heart disease, improve both blood pressure and blood sugar levels, maintain body weight, reduce obesity risks, and even improve your mental state.
There may actually be some middle ground in the debate. As New York Times health columnist Jane Body pointed out last year, there is plenty of compelling research showing the health benefits of what's called high intensity interval training (HIIT).
It's what it sounds like -- a person engaged in moderate activity, such as brisk walking, that steps up the pace for a short interval, repeating the process throughout the workout.
“Researchers have found that repeatedly pushing the body close to its exercise limits for very brief periods, interspersed with periods of rest, is more effective than continuous moderate activity at improving cardiovascular, respiratory, metabolic and mechanical functions,” Brody wrote.
As with any new exercise routine, it is wise to discuss it with your healthcare provider before starting.