Brisk Walking as Beneficial for Heart as Running

  I've always admired people who can run for miles without the slightest ache or pain.  Although I enjoy running immensely I've had to surrender to the fact that my body doesn't feel the same way.  Like many other Americans, I now turn to more knee-preserving activities like cycling, swimming and brisk walking for cardiovascular exercise. 
  If you're a former runner who's had to reluctantly switch to walking, be encouraged!  New research indicates that brisk walking can be as good for your ticker as running. 
From Science World Report
  In order to maintain good physical and mental health, many people consider running. It is considered good for the heart as it strengthens the heart, and also lowers the actual resting heart rate. But a latest finding asserts that brisk walking is as good for your heart as running.
The study, published in the American Heart Association journal Arteriosclerosis, Thrombosis and Vascular Biology, states that brisk walking can reduce the risk of high blood pressure, high cholesterol and diabetes as much as running does.
For the current study, researchers focused on two groups, runners and walkers. They analyzed 33,060 runners who were part of the National Runners' Health Study and 15,045 walkers who were part of the National Walkers' Health Study. The participants belonged to the age group of 18-80 years. Of them, 21 percent men were walkers and 51 percent were runners.
Previous studies have based their evaluations on time but this study assessed walking and running expenditure by distance. Apart from this, the participants were asked to fill in a questionnaire that collected their activity data.
"Walking and running provide an ideal test of the health benefits of moderate-intensity walking and vigorous-intensity running because they involve the same muscle groups and the same activities performed at different intensities," Paul T. Williams, Ph.D., the study's principal author and staff scientist at Lawrence Berkeley National Laboratory, Life Science Division in Berkeley, Calif., said in a press statement.
The researchers noticed that an equal amount of energy used in moderate intensity walking and vigorous intensity running resulted in a similar reduction in the risk for high cholesterol, diabetes and high blood pressure.
Williams continued to say that, greater the distance the runners ran and walkers walked, the more they gained health benefits. The health benefits were comparable only if both the groups burned the same amount of energy.
The risk for first-time hypertension was reduced by 4.2 percent in runners and 7.3 percent in walkers. Apart from this, running lowered first-time cholesterol by 4.3 percent and walking by 7 percent. The first-time diabetes in runners dropped to 12.1 percent, and in walkers it dropped to 12.3 percent. Coronary heart disease dropped 4.5 percent by running and 9.3 percent by walking.
"Walking may be a more sustainable activity for some people when compared to running, however, those who choose running end up exercising twice as much as those that choose walking. This is probably because they can do twice as much in an hour," Williams said.