For stronger shoulders, says Wismer, shoulder shrugs are mostly for professional bodybuilders. Most other people should skip these and focus on arm and back moves.
Shoulder shrugs target only the trapezius muscles that run along the top of the shoulders and the neck, reinforcing postural problems and contributing to shoulder tension. To tone the top of the arms, work the deltoids, such as with straight arm lifts to the sides.
If you want to primarily strengthen your core, this move works wonders. But to strengthen your back and arms, traditional rows are more effective.
“This move works stability,” says Aguilar. “But the position minimizes the force producing capability of the rowing muscles.”
In layman’s terms: The balance challenge that comes from holding a one-armed plank will limit your ability to row a heavy weight with proper fitness form and adequate force.
Inner and outer thigh machine
Not only is this possibly the most unflattering machine at the gym, it’s might not be the most effective.
“When you use this, you’re probably sitting with bad posture and not using your abs,” says Wismer. “You can strengthen the same muscles leg by doing a squat, dead lift, or lunge. Plus you’ll target several more which will be better for overall strength and weight loss.”