"That cycle is what keeps you metabolic rate elevated after you leave, some say up for 24 hours," Ernster said.
Don't count on counting. This is not the slow-moving up and down method of dumbbell work, but rather a swinging motion using your "power house" - hips and glutes in action.
Unlike a regular weight that has symmetrical poundage, a kettle bell is heavy at the base with a big solid handle for grabbing, so there are some rules to form before you let it fly.
"It's essentially a cannon ball with a handle on it. They were basically Russian fishing weights," Ernster said.
You need to have your shoulders back, chest lifted, core contracted and most importantly, stay in control. Make sure you have about four feet all around you for swinging.
Kettle bells can start as low as 4 pounds to about 206 pounds.
A 9-pound iron kettle bell costs about $30. There are plastic-coated bells available that are easier to use, but they are a bit more pricey.
Ernster says this is one fitness toy you won't want to grab and go. Initial instruction is a must, as it is easy to get hurt if you don't know what you're doing.
With large full-body swinging motions, good form is really important.
"The more movement you have with an exercise the more risk there is, the more benefit there is," Ernster said.
A study done by the American Council on Exercise found that 20 minutes of kettle-bell training beat out 30 minutes on the treadmill along with 30 minutes of traditional strength training. Clearly taking a step in the right direction is changing up your routine and putting everything into the swing of things.