Posted by Brigham and Women's Hospital November 13, 2012
We all know that exercise is good for you, but how good? While previous studies have shown the link between physical activity and a lower risk of premature death, the actual number of years of life expectancy gained from different physical activity levels has been unclear — until now.
In a new study from Brigham and Women’s Hospital (BWH), in collaboration with the National Cancer Institute, researchers examined the relationship between physical activity and mortality or life expectancy among more than 650,000 participants over a ten-year period. The findings showed that physical activity was associated with longer life expectancies across a range of activity levels and body mass index (BMI) levels.
“We found that adding low amounts of physical activity to one’s daily routine, such as 75 minutes of brisk walking per week, was associated with increased longevity: a gain of 1.8 years of life expectancy after age 40, compared with doing no such activity,” explained Dr. I-Min Lee, an associate epidemiologist in the Department of Preventive Medicine at BWH and senior author on this study. “Physical activity above this minimal level was associated with additional gains in longevity. For example, walking briskly for at least 450 minutes a week was associated with a gain of 4.5 years. Further, physical activity was associated with greater longevity among persons in all BMI groups: those normal weight, overweight, and obese.”
Participation in a low level of physical activity, comparable to up to 75 minutes of brisk walking per week, was associated with a 19 percent reduced risk of death compared to no such activity. This translated to a 1.8 year gain in life expectancy after age 40, compared with no activity. For those people who did the equivalent of 150–299 minutes of brisk walking per week — the basic amount of physical activity currently recommended by the federal government — the gain in life expectancy was 3.4 years.
The benefits of physical activity were seen in both men and women, and among white and black participants. Just as importantly, the increase in life expectancy was observed among people who were either normal weight, overweight, or obese. Researchers found that patients who were both normal weight and active saw the largest gains in life expectancy, gaining an average of 7.2 years, compared to those with a BMI of 35 or more who did no leisure time physical activity. However, even among persons who were obese, even a small amount of exercise was associated with greater longevity.
Working exercise into your life is easier than you think. The Centers for Disease Control and Prevention (CDC) recommends 150 minutes a week for adults aged 18-64 years old. To meet this goal, the CDC suggests breaking up your daily exercise into smaller chunks of time, even as little as ten-minute segments; walking is an easy and inexpensive way to meet your exercise goals. Using a pedometer, track your current steps for one week, then set a goal to increase this each week by 10 percent until you reach 10,000 steps. For more tips, visit the BWH Health e-Weight website.
How many steps are you walking each day? We’d love to hear how you’re working exercise into your daily life.
– Jamie R