Let’s be real: The gym is a jungle of grunts, sweat, and way too many people doing weird stuff with dumbbells. Given the million exercises out there, you’d think packing on muscle would be a breeze, but some moves are about as useful as a chocolate teapot when it comes to getting swole.
As a Ph.D. scientist who’s dissected more hypertrophy studies than you’ve had protein shakes, I’m here to call out the exercises that are a straight-up waste of time for anyone looking to build muscle mass who doesn’t have three hours a day to screw around in the gym. Don’t worry, I’ll tell you what to do instead.
1. Wrist Curls: Forearm Flexing for the Instagram Aesthetic
You’ve seen the guy in the corner, grunting through wrist curls like he’s sculpting forearms for a Popeye audition. Sure, they’ll pump up your flexor carpi whatevers, but for hypertrophy? Not worth the effort. Studies show isolated forearm training adds minimal mass compared to compound lifts that hit multiple muscle groups. Basically, your forearms get plenty of love gripping heavy bars; wrist curls are just fluff.
Swap It: Ditch the wrist curls for barbell rows, deadlifts, heavy shrugs, or dead hangs from the pullup bar. They’ll blast your back and traps while giving your forearms a real workout—no wrist-twirling required.
2. Side Bends: Chasing That V-Taper (Spoiler: Nope)
Grabbing a dumbbell and flopping side to side like a metronome might feel like you’re carving a V-taper, but it’s a hypertrophy dud. Side bends mostly target your obliques with low mechanical tension, which isn’t your quickest route to packing on size. Plus, thickening your obliques can make your waist wider, not narrower, anyway, so I don’t recommend focusing on them if you’re after chiseled midsection. Bro, your six-pack dreams just left the chat.
Swap It: Weighted planks or hanging leg raises support core stability and a tighter midsection.
3. Smith Machine Squats: The Safety Net That Screws Your Gains
The Smith machine squat looks legit—until you realize it’s a muscle-building snooze-fest. By locking you into a fixed path, it reduces stabilizer muscle activation and cuts the load on your glutes and hamstrings compared to free-weight squats. Research proves it! And less muscle recruitment means less muscle growth. Plus, the Smith machine is the gym equivalent of training wheels—cute, but not for getting jacked.
Swap It: Full range-of-motion barbell back squats can’t be beat. They offer full muscle activation for full gains. Drop the crutch and you’ll feel the difference quickly.
4. Donkey Kicks: Booty TikTok Hype That Falls Flat
Thanks to social media, every newbie gym-goer seems to be donkey-kicking their way to nowhere. This glute-isolation move sounds sexy, but can only be done with low resistance and therefore has little impact for hypertrophy. Studies show compound lifts outpace isolation moves for building muscle mass, especially in big groups like the glutes. You’re not a donkey, and your gains shouldn’t bray like one.
Swap It: Heavy hip thrusts or Romanian deadlifts are science-backed and guaranteed to make your glutes pop without the barnyard vibes.
5. BOSU Ball Anything: Wobble Your Way to Zero Growth
Some people love hopping on a BOSU ball for “functional” squats or push-ups, thinking they’re unlocking secret gains by wobbling through their reps. Newsflash: Instability kills hypertrophy. Research shows that unstable surfaces tank your force output and muscle activation compared to solid ground. If you’re trying to get big, ditch the circus act; muscle needs tension, not a balance test.
Swap It: Leave the balance training for yoga class and stick to regular squats and bench presses instead of BOSU moves. Make them heavy and you’ll pack on plenty of beef.
The Bottom Line: Your Time Is Too Precious for Trash Exercises
Building muscle isn’t about doing all the things; it’s about doing the right things. Wrist curls, side bends, Smith squats, donkey kicks, and BOSU ball nonsense might burn a few calories or impress your gym crush for five seconds, but they won’t cut it for hypertrophy. Science says stick to compound lifts, max out mechanical tension, and keep the fluff off your program. So next time you’re tempted by a shiny new exercise, ask yourself: “Is this getting me jacked, or just jacking around?” More often than not, your gains benefit best from sticking to the basics. (Need a little more guidance? Make sure your workouts check these boxes if you want to pack on size.)


Known as ‘The Muscle Ph.D.,’ Dr. Jacob Wilson has a knack for transforming challenging, complex concepts into understandable lessons that can support your body composition and health goals. A skeletal muscle physiologist and sports nutrition expert, Wilson is a leader in muscle sports nutrition. As the CEO of The Applied Science & Performance Institute, he researches supplementation, nutrition, and their impact on muscle size, strength, and power.



