I don’t know if the traditional round shape of barbell weight plates and their dumbbell cousins is intentional or a historical accident. What I do know is that the introduction of hexagon-shaped dumbbells and 12-sided weight plates has been an absolute fiasco. (If you haven’t come across such equipment in your gym, consider this post a cautionary tale.)
When equipment manufacturers began selling polygonal weight plates about a decade ago, fitness magazines hailed their arrival as the greatest invention since, well, the wheel. These newfangled plates also included handles cut directly into the metal, an actual improvement over the standard ponderous plate.
Nevertheless, the problem caused by a weight plate with corners becomes immediately obvious to anyone performing deadlifts. When the plate hits the floor at a pointed edge, gravity rocks the barbell (and everything attached to it) forward until the plate comes to rest on the next flat side. Literally stumbling through a set of deadlifts is, let’s say, suboptimal.
Some dumbbell manufacturers have also eschewed the circle, again with disastrous results. First, the lifter needing to transport heavy dumbbells from the rack to the open bench 20 ft. away would much rather roll the weights there than train for the Carry & Drag. Second, I find that the edges of hexagonal dumbbells cut into the shoulder during all kinds of presses. Finally, geometric shapes just don’t slide cleanly into the dumbbell rack next to one another.
So I’ll ask again: Does anyone designing equipment for the gym have any actual experience in the gym?