A study from Iowa State University, which is published in Medicine and Science in Sports and Exercise, finds that lifting weights for less than an hour a week may reduce your risk for a heart attack or stroke by 40 to 70 percent. Spending more than an hour in the weight room did not yield any additional benefit, the researchers found. The results show benefits of strength training are independent of running, walking or other aerobic activity. In other words, you do not have to meet the recommended guidelines for aerobic physical activity to lower your risk; weight training alone is enough.

Lee, associate professor of kinesiology, and his colleagues analyzed data of nearly 13,000 adults in the Aerobics Center Longitudinal Study. They measured three health outcomes: cardiovascular events such as heart attack and stroke that did not result in death, all cardiovascular events including death and any type of death. Lee says resistance exercise reduced the risk for all three. "The results are encouraging, but will people make weightlifting part of their lifestyle? Will they do it and stick with it? That's the million-dollar question," Lee said.

Since incorporating weight training to our normal life pattern is difficult, Lee says a gym membership may be beneficial. Not only does it offer more options for resistance exercise, but in a previous study, Lee found people with a gym membership exercised more. While this latest study looked specifically at the use of free weights and weight machines, Lee says people will still benefit from other resistance exercises or any muscle-strengthening activities. Using the same dataset, Lee and his colleagues looked at the relationship between resistance exercise and diabetes as well as hypercholesterolemia, or high cholesterol. The two studies, published in Mayo Clinic Proceedings, found resistance exercise lowered the risk for both.

Less than an hour of weekly resistance exercise (compared with no resistance exercise) was associated with a 29 percent lower risk of developing metabolic syndrome, which increases the risk of heart disease, stroke and diabetes. The risk of hypercholesterolemia was 32 percent lower. The results for both studies also were independent of aerobic exercise. "Muscle is the power plant to burn calories. Building muscle helps move your joints and bones, but also there are metabolic benefits. I don't think this is well appreciated," Lee said. "If you build muscle, even if you're not aerobically active, you burn more energy because you have more muscle. This also helps prevent obesity and provide long-term benefits on various health outcomes."

Read More