Study: 30 minutes of exercise a day is not enough

“The findings challenge the notion of a 30-minutes-a-day magic number for exercise.”

If you’re among of the millions of Americans who dutifully carve out 30 minutes a day for the moderate-intensity exercise recommended by experts based on the idea that you’re doing all you can for your heart, you’re in for some disappointing news. A new study finds that that amount of activity may not be good enough.

Researchers reviewed 12 studies involving 370,460 men and women with varying levels of physical activity. They found that those following the 30-minutes-a-day guidelines issued by the American Heart Association had “modest reductions” in heart failure risk compared to those who did not work out at all. But those who exercised twice and four times as much had “a substantial risk reduction” of 20 percent and 35 percent, respectively.

The findings challenge the notion of a 30-minutes-a-day magic number for exercise. Instead, research found that physical activity and heart failure may be what they called “dose dependent,” meaning that higher levels of physical activity appeared to be linked to a lower risk of heart failure. That association appeared to hold across age groups, gender and race.

Heart failure, which occurs when the heart cannot supply enough blood to the body, affects more than 5.1 million adults in the country, and results in health-care costs exceeding $30 billion per year. The American Heart Association reports that it accounts for “a significant proportion” of hospitalizations and deaths of older Americans. Officials suggest that this “growing epidemic” is expected to increase by 25 percent from 2010 to 2030.
American Heart Association guidelines recommend that middle-aged adults engage in at least two hours and 30 minutes per week of exercise such as brisk walking. Walking 30 minutes a day, for instance, may not be enough for a middle-aged person with hypertension, which presents an increased risk of developing heart failure. Those with diabetes or a history of heart failure also would benefit from talking with their doctors about increased physical activity.

If there’s no way you can cram in 300 to 600 minutes of exercise a week, don’t despair. Plenty of research shows that lower amounts, even microbursts of intense 10 to 15 minutes of activity, can be beneficial.

In fact, the Centers for Disease Control and Prevention notes that one minute of vigorous activity is about the same as two minutes of moderate activity, so you can do a mix of the two each week.

Vigorous aerobic activity is defined as a something that makes you breathe hard and fast and that pushes up your heart rate pretty high. Here are some examples:

• Jogging or running
• Swimming laps
• Riding a bike fast or on hills
• Playing singles tennis
• Playing basketball
• Build up over time

As for moderate-intensity exercise, there are plenty of activities you may not have thought of that can help your heart and “count” toward your exercise total. Examples include:

• Walking fast
• Doing water aerobics
• Riding a bike on level ground or with few hills
• Playing doubles tennis
• Pushing a lawn mower

To learn more about this study, click here.