All it takes is six minutes a day to build a bigger upper body — that’s what the ads say, anyway.

You stand up, gripping the dumbbell-like object with both hands and keeping your arms locked in place at roughly a 90-degree angle. Then you shake it up and down, feeling the spring loaded weights on either end send mini pulsations through your arms.

The Shake Weight became an instant sensation immediately after the company that created it, FitnessIQ, decided to launch a few late-night commercials advertising its newest product. Over two million Shake Weights have been sold to date, and the device has been featured on “The Ellen DeGeneres show,” made fun of on “Saturday Night Live” and even popped up in an episode of HBO’s “Hard Knocks: Training Camp With the New York Jets” series.

But does it really work? Or is it just a $30 scam that’s provided our population with some laughs because of its sexually suggestive nature?

“It’s definitely better than doing nothing,” said Ryan Greene, a second year master’s student in the University of Illinois’ kinesiology program. “But if you’re going to invest money in a workout program, you’re better off doing it elsewhere.”

Greene added there are three types of muscular exercise — isometric training, concentric training and eccentric training. Isometric training, which is what the Shake Weight is based on, occurs when your muscles are generating a significant amount of force but are not moving.

“It’s like pressing against a wall,” Greene said. “You’re using a lot of force to hold your muscles in that formation, but that static exercise isn’t going to do anything for your cardiovascular fitness.”

He said another downside of the Shake Weight is that it will only train your muscles at the angle which the user holds it at. So the Shake Weight will hit your biceps and triceps (the smallest muscle groups in your upper body, respectively) as well as a bit of your chest, but it will only do so at one angle. This is much less advantageous than putting your muscles through a full range of motion.

On the other hand, concentric exercise occurs when your muscles move into a contracted position (think of the way you tense-up while doing a basic bicep curl), and eccentric exercise is defined by a stretching, or elongating, of the muscles (case in point: the way your chest stretches out as you lower the bar on a common bench-press repetition).

Greene said human muscle fibers interact with each other almost like the teeth on a zipper — so as they contract, they can work together while generating less force individually. This is why eccentric exercise works your muscles the hardest — think of it as if the zipper’s teeth are being slowly stretched apart but still required to produce the same total force against whatever object they are moving.

Still, what about the Shake Weight’s claim that it’s driven by “a completely new workout technology called dynamic inertia” that promises to work out your entire upper body in six minutes?

“In the scientific community, if you presented a paper with the principle of dynamic inertia in it, they would just laugh at you,” Greene said. “It doesn’t exist.”

So if you do have only six minutes a day to work out that upper body, try something else instead — like three minutes of pull-ups and three minutes of pushups.

“You’d get much more out of that,” Greene said. “You can minimize your workout time by just doing high-intensity, short-duration exercise and eliminating periods of resting.”

So my verdict? Skip the Shake Weight and stick with the conventional exercises instead. I’m sure you can find something else to spend that $20 to $30 on, and you won’t have to put up with the snickers and giggles from the roommates.

Peter is a senior in Media.