All About Olympic Bars
There's a wide range of views about lifting bars, Olympic bars particularly. For some folk, they're a ho-hum matter of just getting something that does what they think is a basic job. With others, there's a broad scope of refinement and a clutch of big benefits to be understood and gained. So much so, it can be a major topic in itself to many trainers. We thought we'd ask a well-qualified customer to give us a broad basic training view of the major aspects of Olympic bars. A kind of start-up primer for people getting into it.
Dave Jordan is an important customer and turns out to be ideal. He starts by saying that important principle aspects of bars are strength, bar diameter, assembly, knurl and finish. When you talk strength you really want to talk tensile strength, not yield strength. Tensile strength is measured in pounds per square inch (psi). Yield strength is the weight the manufacture claims the bar can handle without bending. Yield strength is irrelevant, it could mean anything, and is almost always based on a static load. In real world usage you want the bar to handle the dynamic force of being dropped. Tensile strength is how the strength of steel bar is measured in the real world. It's not a standardised measurement but it does indicate that the manufacturer has actually made some effort to source good steel. Good bars are made from steel with a tensile strength of around 180 psi and up, the best are 200+psi.
A lot of barbell enthusiasts talk about "whip", or the springiness of a bar. They are talking about how easily a bar will bend before returning to absolutely straight. Advanced Olympic lifters use this "whip" to assist them by effectively bouncing the weight up their bodies. This has nothing to do with the strength of the bar, or any magic metallurgical property of the steel used. This is simply a function of the bar diameter, and possibly the assembly (sleeve length, tolerances etc). The thinner the bar, the more flexible it will be. This is why men's Olympic lifting bars are typically right on 28mm. Powerlifters and regular weight trainers generally perform more static lifts, so prefer a more rigid barbell. This is why powerlifting and general training bars are 29 mm+.
There are a number of variables when it comes to the assembly of bars. The one which gets the most attention is whether the manufacturer opts for bushings or bearings. Bushings are good, they are cheaper, and more robust. Bushing bars are sufficient for most intents and purposes. They require little maintenance and care, save for a few drops of oil now and then.
If you are doing a lot of Olympic lifting, you might consider a bar with needle bearings. These have better spin. This means there is less resistance acting on the lifter's wrists when he or she pulls under the bar during a clean or snatch. It's marginal, and many people feel the spin of a well oiled bushing bar is more than sufficient for the quarter rotation of the bar during an Olympic lift. Needle bearing bars also require maintenance, and need to be looked after as the bearings can be damaged. Nonetheless, the best bars designed for these lifts have needle bearings (e.g. Eleiko).
What you need to be wary of is cheap bearing bars. Dressing a cheap bar up with cheap bearings does little to improve the quality of the bar. A good bushing bar will outperform (and definitely outlast) a cheap bearing bar.
The other key factor for assembly is how the sleeves are attached to the bar. Cheap bars will have a thread in the end of the bar, the sleeve slides over the bar and is held in place by a hex bolt. If you look at the end of the bar and see a hex bolt, this is usually a telltale sign of a budget bar. This is not just an aesthetic thing, there can be a lot of stress on these bolts, they've been known to work themselves loose, and even break!
The sleeves of high end bars are often held in place by snap rings. These may be visible from the end of the bar, or covered by dust caps. Another sleeve assembly design uses a pin through the sleeve which sits in a groove in the shaft itself (the well-known Texas Power Par is one example).
A good bar will have minimal "play" in the sleeves, and when spun will complete at least a few smooth rotations before coming to a stop. It doesn't need to spin like a roulette wheel, this is not important in real world use, but it should rotate smoothly with no noticeable sticking points.
Knurl is a personal preference thing. Some like it rough! Knurl can be described in many ways, but the nuances can only really be appreciated in person, with the bar in hand. Generally speaking though, Olympic and general training bars tend to have a softer knurl so as not to unnecessarily damage the lifter's hands. Power lifting bars typically have a deeper, more aggressive knurl.
Olympic and powerlifting bars have two very distinct knurling patterns. These largely pertain to the gaps or rings in the knurl which guide hand placement. The International Weightlifting Federation have one set of specifications, the International Powerlifting Fed have theirs. Many manufacturers produce bars with both markings (hybrid) and some with unique markings which do not pertain to either specification.
Interestingly, both IWF and IPF specs call for a centre knurl. This knurl is to provide grip on the lifter's back for squatting movements. Some Crossfit and so called "Olympic lifting" barbells omit the centre knurl as it is considered unnecessary for these lifts, and even a hazard to the neck of the lifter in the clean position.
Regardless of the knurl pattern, the mark of a quality bar is the same with regard to knurling. If you look at the knurling start and stop points along the bar, you should see a nice, uniform, even knurl. Inferior bars will have knurl which feathers out, and is inconsistent along the shaft. It's evidence of poor craftsmanship and lacklustre quality control.
Bars can be left as bare steel (especially if manufactured from stainless steel), or given a surface treatment such as black oxide, chrome or zinc. Some manufacturers produce bars with one finish on the shaft and a different finish on the sleeves.
There are a variety of factors to consider with regard to finish. The finish will determine the amount of maintenance the bar will require, with options like chrome plating and stainless steel being very low maintenance. Bare steel, zinc and oxide treatments will provide a great feeling finish on the bar, while chrome can be slippery.
Finally, the finish may impact on the price of the bar, although this is difficult to make a blanket statement. Budget bars are usually finished with a budget chrome finish, which is cheap and somewhat effective at preventing rust. Gym users are used to seeing shiny, chrome bars so this is the most common finish used. The downside is that the chrome finish is typically applied after the knurl is cut, which can have the effect of partially filling in the knurl, and softening it.
That is not to say that all chrome bars are cheap. On the contrary, Eleiko produces all its bars with a chrome finish.
Bare stainless steel is generally the most expensive "finish", but it is obviously not a finish at all, it is an entirely different grade of steel. Bare stainless can be unsuitable for barbell sleeves however, and a coating may be applied to these to protect the underlying steel. Many manufacturers opt for hard chrome sleeves as this finish provides good protection from the harsh scratching of plates being loaded and unloaded from the bar.
Due to the maintenance required, ordinary bare steel bars are uncommon, save for some hardcore powerlifting bars. Bare steel provides great feel, and over time will develop a nice final finish which will protect the bar from rust. It is uncommon for budget bars to be produced in bare steel.
Black oxide and zinc provide a happy medium for mid-range bars. These coatings provide some rust prevention, although still require the occasional oiling to preserve the finish. They also have a similar feel in the hand to bare steel. They also look great. When combined with hard chrome sleeves, this finish provides excellent bang for buck for lifter's looking for a mid-range barbell.