Physical Activity After a Heart Attack, Is It Possible? Should It Be Done?

A study published in November 2019 indicates that: initiating or maintaining a high level of moderate-to-high intensity physical activity after experiencing a myocardial infarction (MI) can help reduce the risk of all-cause mortality in men, according to research presented at the American Heart Association 2019 Scientific Sessions, held from November 16–18.

"Many studies have shown that physical activity is good for health, as it decreases the risk of chronic diseases, including heart disease, and improves survival and quality of life," said Laila Al-Shaar, PhD, MPH, of Harvard University, in Boston, as reported by Elsevier's PracticeUpdate. “However, our knowledge is very limited regarding the benefit of discretionary physical activity after people experience an infarction. Therefore, we wanted to understand the relationship between discretionary physical activity, its intensity, and changes in relation to survival among those who suffered a heart attack.”

The investigators used data from the Health Professionals Follow-Up Study cohort to track male MI survivors who responded to questionnaires about their physical activity levels before and after experiencing an MI. Among these men, the short-term change in physical activity was calculated as the absolute difference between what was reported before and immediately after the MI.

During a mean follow-up period of 14 years, there were 1651 incident cases of MI, including 678 documented deaths. Of these, 307 were due to cardiovascular disease (CVD). Self-reports of physical activity before and after MI diagnosis were inversely associated with all-cause and CVD mortality. Before MI, when comparing men who engaged in at least 21 metabolic equivalent hours of task (METs) per week, which is equivalent to about 7 hours per week of moderate to vigorous physical activity, with men who engaged in 1.5 or fewer METs per week, the hazard ratio for all-cause mortality was 0.73 (95% confidence interval 0.59-0.89; P-trend = 0.03). The equivalent comparison among men after an MI yielded a very similar hazard ratio (0.74, 95% confidence interval 0.60-0.92, P-trend = 0.02).

After MI, men without gait impairment were classified into one of four categories based on the reported change in pre-MI physical activity levels: 1) maintained low (n = 322), 2) decreased (n = 201), 3) increased (n = 303) or 4) maintained high (n = 825). Men's long-term physical activity change was calculated as the difference between the accumulated average of repeated physical activity measurements in the pre- and post-MI periods.

Men who maintained a high level of physical activity before and after MI (category 4) had a 39% lower risk of all-cause mortality compared to those who maintained low physical activity (category 1). Similarly, those who had a long-term increase in physical activity from before to after MI (category 3) had a 27% lower risk of all-cause mortality compared to those in category 1. “This [latter] survival advantage was not seen among those who had only a short-term improvement in their physical activity from before to after the [MI],” noted Dr. Al-Shaar.

The results were consistent after adjusting for MI severity. Furthermore, even walking, a relatively low-intensity activity, was associated with benefits. Half an hour or more of walking per day after MI was associated with a 29% reduction in mortality (hazard ratio of 0.71, 95% confidence interval of 0.58 to 0.84), regardless of walking pace. "Those who walked for at least 2.5 hours per week after [an MI] had better survival than those who walked less than 30 minutes per week," said Dr. Al-Shaar. "This survival advantage was observed regardless of walking intensity or other types of physical activity."

Still, more vigorous walking provided even greater benefits. Walking pace after MI was inversely associated with mortality (hazard ratio 0.67, 95% confidence interval 0.49-0.92).

Dr. Al-Shaar concluded that “the findings support the latest 2018 Physical Activity Guidelines for Americans and current guidelines established by the American College of Cardiology/AHA for the management of patients with [an MI], which endorse a post-hospitalization plan that includes the promotion of regular physical activity and other lifestyle factors.”

She noted that "the results on changes in physical activity are comparable to a similar study previously done in 856 postmenopausal women in the Women’s Health Initiative (mean follow-up time of 7.2 years)."

Obviously, an exercise program should be conducted by a qualified physician and other cardiovascular rehabilitation professionals. NEVER DO ANYTHING WITHOUT PROPER SUPERVISION!

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