PLYMOUTH, Minn. -- The key to losing weight might be sitting right there in your house or apartment building.

A new study claims walking upstairs can burn 20 times more calories than walking on flat ground. That's a significant spike compared to previous research.

What are the benefits of using stairs for exercise? And how does it compare to running? Good Question.

If you want to step up your exercise routine, then simply step up to the stairs.

"I feel like it's the best cardio workout," said Mike Leonard as he stood next to a stair machine at the Life Time in Plymouth.

"I can target every muscle in my leg group," added Life Time member Brandon Kramer.

What are the benefits of climbing stairs?

"Stairs are a part of your life... they actually train you to do life really well," Keri Anderson, a fitness professional at Life Time, said.

Exercising on stairs not only prepares you for several flights of them, but the unique terrain our world presents, whether you're an avid hiker or hunter like Kramer.

"I typically only start doing the stairs, starting like July, August, September just to prep myself for the upcoming (hunting) season," he said.

Why should someone choose stairs for exercise versus running? One reason involves longevity.

"This is an awesome way to get the heart rate up without the impact on the joints. The knees, the ankles, the back can take a big impact when you are running," said Anderson.

Leonard compared the stair machine to an escalator, saying it's much easier on his knees. It's also a lot faster at burning calories.

According to a recent study reported on by the Associated Press, moving one kilogram of body mass over one horizontal meter burns half a calorie. But move that same kilogram vertically on stairs and it burns 10 calories, or 20 times more than walking.

Previous research shows it was only three times higher than walking.

Rather than comparing workout styles, Anderson wants people to focus on how fast their heart is pumping as it relates to burning calories.

"It's totally dependent on your heart rate and how hard you're working," she said.

The higher your heart rate, the more calories you burn regardless of the workout choice. The key, she said, is how long someone can sustain that higher heart rate.

Walking down stairs has its benefits as well. It burns as many calories as walking on flat ground, with some researchers saying it can burn up to five times more.

"Going down actually is a little bit more productive in muscle building. It's hard on the body. It's more stress on the joints and so it is actually a good thing to train," said Anderson.

Even how you step on stairs can alter the workout. Pressing on your heels or crossing your feet activates new muscle groups in your legs.

"If you could throw (stair stepping) into your mix, amongst the treadmill and amongst the bikes, do it," she said.

Maintaining good posture on a stair machine is important. Anderson said people need to stand up straight and engage their core, not be hunched over.