Bumper plates are used for olympic lifts – the “snatch” and the “clean and jerk”. The way they are constructed means they are tailor made for these two lifts.
There are several ideal features that make bumper plates perfect for these llifts:
- Bounce – Bumper plates are solid rubber weight plates. Unlike other plates, they not iron with a rubber coating but solid rubber all the way through. The exception is the steel collar in the middle, described below. The rubber used is typically a high-density rubber that really does not bounce that great but still dampens the shock force when it hits the ground, enough to protect the plates and bar, as well as the floor (assuming the right flooring is used).
- Uniform Size – Bumpers need to all hit the floor and share the force of the drop, so it would not do if they were different sizes like iron plates, as the smaller ones would never touch the ground and would add additional load to what the larger plates have to absorb. Bumpers are typically all about 450mm (17.72″) diameter, regardless of weight. Some brands are made a little smaller, such as 17.5″. IWF regulation size is 450mm. So it is usually possible to mix and match bumpers with no problems once you determine the size you’re using. A tape measure will do the trick. They are usually one of the above two sizes, and you should not encounter any weird sizes like 17.6″.
- Strong Hub – The center hub or collar has to be strong enough to not deform or detach from the extreme shock of being dropped. In the past, brass collars were used, but before long people found that the lower cost of brass was not worth it, as the brass was too soft a metal and would deform. Steel is good. Competition bumper plates have a much larger hub that is machined to size and clearly is not going to deform under any circumstances.
Iron plates or rubber coated plates will not meet any of the above requirements. Even people who do deadlifts, and not olympic lifts, often use bumper plates for a couple of the same reasons. They want to be able to drop the bar on those heavy max attemps if needed without damaging anything, and they want the plates to be the same size.
There are additional features of various bumper plates, depending on how much you want to spend or your preference.
- Competition Bumpers – These are mentioned above. They are made with a larger steel hub, which weighs more than rubber, so the entire plate is thinner than any “economy” bumper plates. This means you can fit more plates on the bar, which is important for competitions where the athletes can go up to several hundred pounds.
- High-Bounce Bumpers – Hi-Temp is the only popular brand of these. Everything else out there is considered “low bounce” or “dead bounce”, meaning they barely bounce at all when dropped. Hi Temps will bounce a LOT. The advantage is the extra protection to flooring. They can even be used in your driveway without damaging the concrete, unlike dead bounce bumpers that would start pulverizing the concrete over time.
- Color Coding – Competition plates are almost always color coded. The reason for it is so athletes can identify the weight at a glance and don’t make any mistakes loading the bar. Lifting an unbalanced barbell is annoying and dangerous. It’s also obvious to spectators when the weight is wrong, so color coding is just an awesome thing to have. Economy bumpers are often just black, because of the extra cost of the color.
For those of you working on your deadlifts, see Kevin Cann’s article on the mobility advantages of doing deficit deadlifts.