Vigorous Exercise 3 Times Weekly Reduces Men's Heart Attack Risk By 22%

Men who do vigorous exercise three times a week were found to have a significantly lower risk of having a heart attack, compared to those of the same age who did not, researchers from the Harvard School of Public Health wrote in the American College of Sports Medicine. The authors added that other important markers included hemoglobin A1c, apolipoprotein B and vitamin D.

Lead author, Andrea Chomistek, Sc.D. and team gathered data on activity levels and biomarkers from adult males from the Health Professional Follow-Up Study (HPFS). Included in the data were insulin sensitivity, cholesterol levels and markers of inflammation. The participants were asked to complete a questionnaire twice a year, in which they wrote about how long they spent each week on leisure-time physical activity.
Andrea Chomistek said:

"We studied vigorous exercise because of its stronger association with coronary heart disease. While we discovered that vigorous-intensity exercise decreases a man's risk of heart attack, we also were able to partially determine why. The benefits of exercise on a man's levels of HDL-C, or 'good' cholesterol, account for approximately 38 percent of that decrease. Other important markers included vitamin D, apolipoprotein B and hemoglobin A1c."

Blood samples were collected from 18,225 adult males, of which 454 had suffered a non-fatal heart attack or had died form coronary heart disease between 1994 and 2004, the period of the study. 412 of those with coronary heart disease were compared to 827 controls and matched for smoking status, age and date of blood donation.

Chomistek said:

"As expected, traditional cardiovascular disease risk factors were more common among cases than controls. Men who suffered a nonfatal heart attack or died from coronary heart disease had less 'good' cholesterol, more 'bad' cholesterol and were more likely to have high blood pressure, high cholesterol and diabetes."

Even though they had identified some biomarkers that could explain the link between physical activity and a lower chance of developing coronary heart disease, the authors stressed that further research on other mechanisms by which physical activity impacts on cardiovascular risk are needed.

Heart disease causes more premature adult male deaths in the USA than any other illness or condition, according to the CDC (Centers for Disease Control and Prevention). From 70% to 89% of all sudden cardiac events occur in males. Almost half of all men who suffer a heart attack before they are 65 years old do not live more than eight years.

In an Abstract in the journal, the authors wrote:

"Participating in 3 h•wk^-1 of vigorous-intensity activity is associated with a 22% lower risk of MI among men. This inverse association can be partially explained by the beneficial effects of physical activity on HDL-C, vitamin D, apolipoprotein B, and hemoglobin A1c. Although the inverse association attributable to these biomarkers is substantial, future research should explore benefits of exercise beyond these biomarkers of risk."

Hemoglobin A1C is monitored to assess the long-term control of diabetes mellitus.

Apolipoprotein B, also known as APOB or ApoB is the main apolipoprotein of LDL (low-density lipoproteins or "bad cholesterol").

HDL-C, also known as high-density lipoprotein is what is often termed the good cholesterol. Higher HDL-C levels are generally associated with a lower risk of coronary artery disease.