Physical activity contributes to cardiorespiratory health and reduced risk for CVD, making physical inactivity one of the leading modifiable risk factors, according to a review published in the Journal of the American College of Cardiology.
“The benefits of being physically active exist regardless of sex, ethnicity or age,” Gerald Fletcher, MD, professor of medicine and cardiovascular disease at Mayo Clinic Florida, said in a press release. “The most active individuals have an approximate 40% lower risk of developing heart disease than those who do not exercise at all.”
To investigate the benefits of physical activity and exercise, along with the effect of physical inactivity, on CV outcomes and overall health, the researchers conducted a systematic review of 25 published studies. Physical activity was defined as bodily movement that takes place in daily activities and exercise was defined as planned, repetitive movement for the purpose of good health and strength, according to the researchers. The definition of physical inactivity included sedentary behaviors like sitting in front of a computer or watching television.
Researchers found that, between 2003 and 2006, the percentage of engagement in sedentary behavior in the United States increased from 55% to 58% and, based on results from the 2008 National Health Survey, 56.5% of respondents did not meet the Physical Activity Guidelines for Americans.
As for the effect of physical inactivity on overall health, a prior study found that physical inactivity contributed to 9% of premature mortality globally, and eliminating physical inactivity could increase the life expectancy of the world population by 0.68 years, the authors wrote in the review. Furthermore, physical inactivity was associated with 6% of CHD, 7% of type 2 diabetes, and of 10% of breast cancer and colon cancer diagnoses, they wrote.
Another prior study demonstrated associations between sedentary behavior and all-cause mortality (HR = 1.24; 95% CI, 1.09-1.41), CVD mortality (HR = 1.179; 95% CI, 1.106-1.257), CVD incidence (HR = 1.143; 95% CI, 1.002-1.729), cancer mortality (HR = 1.173; 95% CI, 1.108-1.242), cancer incidence (HR = 1.13; 95% CI, 1.053-1.213) and type 2 diabetes incidence (HR = 1.91; 95% CI, 1.642-2.222).
A meta-analysis reviewing 13 studies revealed that mortality rates were highest in participants with the least physical activity (sitting > 8 hours a day and performing < 2.5 metabolic equivalent of task hours per week; HR = 1.27; 95% CI, 1.22-1.31) and that physical activity was associated with lower all-cause mortality for exercise (HR = 0.58; 95% CI, 0.54-0.63) and nonexercise physical activity (HR = 0.7; 95% CI, 0.66-0.74).
Among patients with CVD, cardiac prevention and exercise programs were associated with lower mortality (RR = 0.72; 95% CI, 0.54-0.95) and at least 4 hours of recreational physical activity (gardening, regular walking) per weekend was associated with reduced mortality in men. In addition, men who began sedentary but started light physical activity had lower mortality rates at follow-up than those who remained sedentary (RR = 0.58; 95% CI, 0.33-1.03).
When attempting to account for the differences in physical activity patterns between people, researchers discovered that being active or inactive may be related to two phenotypes, which each prompt individuals to engage in distinct behaviors. In addition to genetics, researchers identified personal (for instance, demographics, social and cultural factors, and psychological and emotional factors) and environmental variables (for example, availability of facilities, type of neighborhood and climate) that may play a role in physical activity habits.
“Just like medication, the right form of physical activity has to be specialized for each patient,” Fletcher said in the release. “Physical activity is no different from smoking cessation or eating a heart-healthy diet. It is up to health care professionals to set an example for their patients in all aspects of life.” – by Melissa J. Webb
Disclosures: The authors report no relevant financial disclosures.