Fitness walking is a fast-paced exercise that gets your feet moving and your heart pumping as Dr.
"Now for fitness walking, this is absolutely what you don't want. We want to be walking at a quick, brisk, vigorous pace, like this," said David Pasion with the Emory School of Medicine.
Fitness walking is a low impact aerobic exercise that's good for your health and easy on your joins.
Some turn to it because of an old injury, or to prevent new ones.
"I used to be a runner, and I hurt myself," said one fitness walker.
"How about to keep my legs looking nice (laugh)!" exclaimed another.
"You can get your social hour in while you're getting your exercise done," said another walker.
Fifty minutes of fast walking burns about the same number of calories as 20 minutes of running.
And like running, it's good for your heart and may improve your blood pressure and cholesterol numbers, as well as your mental health.
So how do you know if you're working hard enough? Check your heart rate.
"For a 40 year old, the low range would be 126 beats per minute, and your high range should be 144 beats per minute," said Pasion.
And try to keep your stride short, longer strides increase the risk for injury to your ankles, knees and hips.
"Start out at three times a week, walking at least 20 minutes each time. Walking keeps you young," he said.