Have you ever looked up the definition of the word "fad?" It's defined as "an intense and widely shared enthusiasm for something, especially one that is short-lived and without basis in the object's qualities; a craze." Pretty much sums up some of the insane things that have become "popular" in the fitness world, doesn't it?

Fitness fads come and (thankfully) go, often leaving little more than a sour taste in our mouths and an eye-roll at "how could we have believed that?" Here are some of the cringiest fitness fads to pop up in the last few years:

Shake Weight – Just one look at the demo videos for this unique weight, and you can understand why it's at the top of this list. It's a highly suggestive movement that never really delivers real resistance training. Just a weird one, all around!

Toning Shoes – These shoes are made with an oddly-shaped heel/forefoot design that is intended to place all the strain of walking on your calves, thus giving you sleek, strong lower leg muscles. They also promote instability, forcing you to recruit stabilizer muscles all over your body. All they really do is look goofy, prevent you from walking properly, and increase your risk of falling/injuring yourself.

Power Balance Bracelets – Do they work? No one knows for sure, but most experts consider these to be little more than gimmicks. While quite a few professional athletes wear them, there's no real science to explain why — or even if — they work.

Toning Clothes – A pair of pants that can tone and tighten your legs, or a shirt that can give you six-pack abs — how realistic does that sound? Toning apparel is a highly popular form of sportswear, but they're basically just pricier, sportier versions of Spanx. They do nothing for your muscles — they just make things look more toned.

Stability Balls/Chairs –Let's get one thing clear: stability balls CAN help to tone your core. However, they're not good for long periods of sitting. If you spend a lot of time sitting down, you need the sort of lower back support offered by a chair. While stability balls are good for watching an episode of TV or playing a game with friends, they're not a replacement for your office chair.

Electric Ab Belts – It seems more and more of these are coming out every year! New "toning ab belts" that send electric shocks into your ab muscles are touted as being revolutionary, but they're hardly effective. In fact, they can even be dangerous (hate to see what happens when one gets wet!). You're better off doing actual crunches or Planks than wearing one of these belts.

People are always looking for ways to make fitness easier and less work. These fitness fads come and go, but what never changes is the effectiveness of resistance training, aerobic exercise, and HIIT training. Spend your time and money on these types of workouts, and you'll see the fitness results you want.

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