THE BLOG
09/25/2014 08:29 am ET Updated Nov 25, 2014

5 Exercises I Just Won't Do

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I'm generally of the mindset that anything that gets someone moving more is an exercise worth doing. Considering that about one-third of adults and 80 percent of teens don't meet the bare minimum when it comes to general exercise recommendations, according to Pacific Standard, I think it's important to do more encouraging than discouraging.

But that doesn't mean every boutique studio or strengthening move or cardio machine was created equal. Some exercises may not deliver the results you'd expect, and others could actually hurt you. Here are five workouts I stay away from.

Sit-Ups and Crunches
First thing's first: No matter how many hundreds of crunches or sit-ups you commit to daily, you can't melt away body fat in specific areas. Your washboard abs won't be revealed until any excess fat is gone from your entire body. Many exercisers are devoted to sit-ups and crunches because they are expecting these (impossible) results.

Second, they're too easy to do incorrectly. The perfect crunch or sit-up engages the ab muscles to lift the shoulder blades toward the ceiling, but it's much more common to see someone pulling from the neck, which could lead to pain (not to mention it cheats your abs out of the hard work).

Last but not least, they may simply be bad for your back. Fitness expert and HuffPost blogger Ben Greenfield likens the spine to a credit card. "In the same way that repeatedly flexing and extending a credit card will eventually lead to wearing out of the card, repeatedly performing the crunching motion can put a lifetime of damaging strain on your back," he previously told HuffPost. Three of the many reasons I'll stick to planks.

The Hip Adductor/Abductor Machine
Without strong hip adductors and abductors -- the muscles that make up your inner and outer thighs, respectively -- you're more likely to suffer from a whole host of exercise-related injuries. But in your everyday comings and goings, you use these muscles in conjunction with all the other muscles in your legs, not to move them in or out like you do on this particularly useless (and let's face it, sort of embarrassing to use in public) machine. Instead, I like to focus on what's typically called functional movements, or those motions you'll also repeat outside of the gym. If you're looking to strengthen your inner and outer thighs, doing some perfect lunges is a safe and smart alternative.

The Leg Extension Machine
I've been lucky enough to make it through a couple of decades of physical activity without any major injuries. Despite being relatively healthy, the leg extension machine has always felt horrible, and I started avoiding it long before I learned exactly what's so wrong with it. The leg extension machine is not only not a functional movement, but it also places a whole bunch of extra stress on the knee -- not to mention gym machines don't necessarily fit every body perfectly, which can add to the strain. "There are so many more dynamic ways to work the quads (the only muscle the leg extension machine works) that activate other muscles in the legs and core," fellow HuffPoster and certified personal trainer Alena Hall previously told HuffPost, like lunges, squats and maybe even your favorite Spinning class.

Anything That "Requires" Heels
I love a good pair of confidence-boosting heels, and I have been known to dance in mine long after my feet have begun to hurt. But a workout class that recommends or even requires high heels not only feels a little demeaning to me, it can also be dangerous. Wearing heels at all places extra strain on the knees, tightens the Achilles tendons, shrinks the calf muscles, can cause bunions and hammertoes, and lead to a host of other not-so-pleasant-sounding physical changes and potential injuries. No matter how easy you think heels are to walk in, there's no denying they throw off balance, which, when combined with a new workout class, is recipe for disaster.

Barre-Based Classes
As a lifelong soccer player, I was skeptical of ballet-inspired workouts from the get-go, but I certainly didn't expect it to feel like torture. The minuscule, precise movements typical of a barre-style class will certainly fatigue muscles, but to me they feel awkward, restrictive and too far from functional. These classes can certainly offer benefits to flexibility, balance, and core strength, but life is too short to do workouts you hate.

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