Short bursts of exercise may help reduce the potentially dangerous spikes in blood fats that occur after fatty meals.

The findings of a new study highlight a way for people who are too pressed for time for a full workout to squeeze in heart-healthy exercise, researchers say.

“Multiple sessions of 10-minute exercise bouts, if repeated throughout a day, accumulate uniquely to lower fats in the blood compared to no exercise or a single long bout of equal duration, intensity and caloric expenditure,” Dr. Thomas S. Altena of Southwest Missouri State University in Springfield told AMN Health.

“Because many people claim lack of time as a reason that prevents participation in a regular exercise program, our results indicate that cardiovascular disease can be prevented through accumulated short bouts that burn approximately 250 calories,” Altena said.

Altena noted that short bouts of exercise are easy for most people to do. But it is important to get a total of at least 30 minutes of exercise each day, he said.

However, taking a slow stroll is not enough to reap cardiovascular benefits. The Missouri researcher noted that exercise must be of at least moderate intensity, meaning a brisk walk or a light jog.

It’s perfectly normal for triglycerides and other blood fats to rise after a high-fat meal, but an abnormally large increase in fats - a condition called postprandial lipemia - has been shown to increase the risk of heart disease. Research has shown that exercise can lower triglycerides and other blood fats after a meal.

Altena’s team studied the effect of short bouts of exercise in 18 men and women who did not exercise on a regular basis.

Over the course of several weeks, participants drank a high-fat meal - a milk shake with heavy whipping cream mixed in - on three occasions.

Twelve hours before one meal, participants exercised continuously for 30 minutes. Another time they exercised for a total of 30 minutes, but the activity was broken up into three 10-minute sessions. Before another meal, they did not exercise at all.

Triglycerides and other blood fats were measured before each meal and several times afterward.

Total cholesterol levels were not affected, but the rise in triglycerides after a meal was less pronounced after intermittent exercise than after no exercise at all, the researchers report in the August issue of the journal Medicine and Science in Sports and Exercise. Continuous exercise did not seem to have an effect on the post-meal rise in triglycerides, according to the report.

According to study co-author Dr. Tom R. Thomas at the University of Missouri at Columbia, the study suggests that some people may benefit from breaking up their daily exercise into several sessions.

But for people who are regular exercisers, those who work out 50 minutes to 60 minutes a day, “it may not be beneficial to split it up,” according to Thomas. “This is the area we are pursuing in future research.”

SOURCE: Medicine and Science in Sports and Exercise, August 2004.