CrossFit Journal - Issue 60.pdf - CrossFit Journal - Gozluk

ISSUE SIXTY

August 2007

Where Barbells Come From

Marty Mitchell,

with Mark Rippetoe

page 1

The First CrossFit Games

Dale Saran

page 7

Reading Between the Lines

Dave Castro

page 9

Combatives Fitness, Part 1

The Warm-Up (Video Article)

Tony Blauer

page 12

On Being a Trainer

(Video Article)

Greg Glassman

page 13

The Turkish Get-Up, Part 3

Overhead Squat Variation

Jeff Martone

page 14

Teaching the Jerk, Part 4

Skill Transfer Exercises

Mike Burgener,

with Tony Budding

page 16

Wrestling with

Dan Henderson

Simple Takedown

Becca Borawski

page 18

Where Barbells Come From

Genetic Potential

Lon Kilgore

page 20

Marty Mitchell, with Mark Rippetoe

The Stretch-Shortening

Cycle and Plyometric

Training

Tony Leyland

The bar is the heart and soul of barbell training. A good bar is the most important

piece of gym equipment you will use in a correctly designed strength training

program. If you are buying it for your home gym, it is the purchase that will have

the greatest bearing on the quality of your training experience. A cheap bar is not

a pleasure to train with, and it may make some of your more critical exercises

more dificult to do. You can’t clean or snatch any real weight with a bar that

doesn’t spin dependably. And you can’t train heavy with a bent bar, or a bar that

might actually fail under a load. Anyone who has trained for any length of time

in a commercial gym has grown fond of a certain bar in the rack, and might even

be inclined to wait for it if it’s being used by someone else. Bars have different

page 22

An Explosive Combination

Michael Rutherford

page 26

The Grinder

CrossFit FRAGO #13,

“SHORTY”

page 28

continued page ... 2

CrossFit Journal • Issue Sixty • August 2007

Where Barbells Come From

...continued

characteristics, and lifters develop a taste for certain types. Buying

one for your home gym should be a careful process since you’ll be

using it every time you train.

Barbell varieties and variables

The type of bar you buy should be determined by what you

want to do with it. Many factors play into the quality of a bar,

and understanding them is important to the informed consumer.

Olympic weightlifting bars are produced in training and competition

grades and are designed to comply with International Weightlifting

Federation speciications regarding markings and dimensions. They

are made to be springier and more lively—“whippy” is the term

usually used—than other types of bars, because of the dynamic

nature of the snatch and the clean and jerk. Powerlifting bars, again

in either training or competition grade, are stiffer than weightlifting

bars, since bar oscillation is not desirable in the squat, bench,

or deadlift. Specialized thicker bars for squats and longer bars

for deadlifts are available and used in some federations. “Multi-

purpose” bars are produced for generalized strength training, gym

use, and the institutional and scholastic markets. The surface of

the bar can be inished in a variety of ways: chrome, zinc, black

oxide, or uninished, or stainless steel can be used. Thicknesses

vary from 25mm for women’s weightlifting bars to 1 3/8 inches for

squat bars, on up to 3 inches for specialized fat bars designed for

grip training. The most common length for general-purpose bars

is 84 inches (7 feet) but they are available in lengths of 72, 60, and

48 inches for speciic needs. They come in a variety of weights,

from 5kg to 60 pounds, with varied knurling depth and marking

options; with bolt, snap ring, or roller pin retainers; with bushing

or needle-bearing sleeves; of domestic or foreign manufacture;

and with expensive, mid-range, or economy pricing. To further

complicate the selection process, bar strength is measured in at

least three ways: tensile strength, yield strength, and test ratings of

2000, 1800, 1500, 1200, 1000, 700, and 500 pounds. Prices range

from less than $100 to around $1000, and the differences among

the offerings across that range can be mind-boggling for someone

just trying to outit a home gym or small training facility.

The byproducts of turning down the steel.

A bar shaft is turned down to size.

The powerlifting market has expanded rapidly over the past

decade, with many sanctioning bodies and an accompanying range

of rules and regulations that permit a variety of equipment to be

used in competition. This creates a market for both competition

and training equipment. Eight-foot squat bars with larger diameter

shafts are now available that deform very little under the heavy

loads modern powerlifting equipment permits lifters to handle.

Longer-than-standard deadlift bars permit the wide stance used in

Sumo-style deadlifting, are thinner for gripping purposes, and offer

more lexibility in the bar to assist the pull from the loor. Stiffer,

thicker power bars are available for bench pressing.These specialty

bars are designed for competition, although sales are increasing

steadily to serious trainees as well. Most companies offer a power

bar suitable for all three lifts, an economic necessity for the school

market and its increasing participation in the sport.

The knurl is applied to a bar shaft.

CrossFit Journal • Issue Sixty • August 2007

Where Barbells Come From

...continued

Olympic weightlifting, however, has one international governing

body and one set of equipment speciications. Several manufacturers

produce bars for competition and training, with separate dimensions

for men’s and women’s equipment. In most cases the grade and

style of a given manufacturer’s men’s and women’s bars are very

similar, if not the same. The major differences are the weight (20kg

for men and 15kg for women) and diameter (28 mm for men

and 25 mm for women). The International Weightlifting Federation

inspects and approves bars and equipment certiied as oficially

acceptable for international competition; at any given time there

may be up to three manufacturers of IWF-certiied barbells. China

alone has over one million registered weightlifters, and the market

for quality equipment there is potentially huge. Competition bars

are typically very expensive, made with very high-quality steel

and roller bearings, and can cost nearly a thousand dollars each.

More affordable but still high-quality bars are available for training

purposes, often made with bushings instead of bearings and with

less expensive steel. For training novice lifters and children, lighter

bars are available in 10kg and 5kg sizes.

The outside flange of a sleeve is turned to size

Weightlifting bars are smaller in diameter than powerlifting bars. A

smaller grip surface is necessary to allow the fast rotation of the

bar, since the smaller diameter rotates at a higher angular velocity,

and the smaller diameter makes it easier to assume the hook grip

favored by weightlifters. A smaller diameter allows for greater bar

lexibility, which facilitates the “whip” desirable in cleans, jerks, and

snatches, but it also requires a more expensive higher grade of

steel. Powerlifting bars need some, but not much, rotation. An all-

purpose powerlifting bar will be thicker than a weightlifting bar.

Whip is not an issue as the bar is carried in the palm, with closed

ingers, or on the back during a lift. In fact, a squat and bench

press bar must be “deader” than a weightlifting bar, because 800

pounds on a whippy bar causes bar oscillation during the lift that

interferes with stability.

There are also a variety of general-purpose bars made for

strength training for athletes, recreational lifters, and team

sports conditioning. Health clubs, high schools, and home itness

enthusiasts may prefer a general-purpose bar to accommodate

budget constraints and the wide range of uses the equipment will

see. For these users, four good bars may be perceived as a better

investment than one great bar. A major bar manufacturer may

offer over forty different styles of bars for sale to wholesalers.

And customization is now a growing trend, with specialty requests

for knurling patterns and marks, sleeve lengths, and special bar

sizes for individuals and organizations. The list of domestic and

international high-quality bar manufacturers includes Power Place

Products, Ivanko, York, Chapman, Eleiko, Leoko, Uesaka, Werksan,

Zhangkong, Texas Power Bar, and Solid Bar.

A sleeve receives finishing on a lathe.

Bar strength measurements

The raw materials and components of a quality bar do not come

from the local hardware store. Shaft steel is a specialty item,

produced by a few manufacturers with the ability to control all

A DOM sleeve is fitted with a flange.

CrossFit Journal • Issue Sixty • August 2007

Where Barbells Come From

...continued

the variables that affect the way a loaded bar behaves, and most of

it is imported from China and Canada. Sources are not as readily

available as manufacturers would like. A materials purchaser who

spends too much time bargain-hunting may be exercising poor

judgment, since bar steel is the most important aspect of the

inished product. When choosing bar stock, a manufacturer will

search for a speciic blend of properties, among them the ability

to accommodate the machining processes that the shaft must

undergo to become a bar.

Perhaps the most important properties of bar stock will be

tensile strength and yield strength. Both of these characteristics

are measured in psi, or pounds of force per square inch, and

information about these two parameters is usually associated

with weightlifting bars. One psi is deined as a force of one pound

applied to an area of one square inch. Tensile strength is deined as

the amount of stress (in psi) a material can take before breaking.

The quick and easy way to select a bar is to buy the highest tensile

strength you can ind.

But equally important is yield strength, which refers to the amount

of stress (again in psi) that a material can take without undergoing

permanent distortion. This distortion is known in engineering

as “plastic deformation,” as opposed to “elastic deformation,”

which is a material’s ability to deform and return to its original

coniguration. Steel with very high yield strength has a very high

threshold of plastic deformation, below which it will exhibit elastic

deformation, always returning to straight when unloaded. In the

simplest terms, you can think of tensile strength as essentially

resistance to breaking, and yield strength as resistance to bending.

The higher these two measures of bar strength are—and the

closer they are together—the better the bar.

Understanding this is critical. For example, a bar with a tensile

strength rating of 195,000 psi and a yield strength rating of 120,000

psi will be next to impossible to break, but, in time, after some

heavy squats, deadlifts and shrugs, you will notice a permanent

bend or bow. On the other hand, a bar with a 195,000 psi tensile

strength rating and a 175,000 psi yield strength rating will turn you

into a lifetime customer for that wise, careful barbell manufacturer.

As it turns out, information on yield strength is not as readily

available as tensile strength info. The knowledgeable buyer will ask

for both.

A DOM sleeve is checked for size.

To muddy the waters, powerlifting bar manufacturers commonly

use pound-test ratings such as 1500-pound test, 1200-pound test,

etc., with the higher pound-test rating being better. Higher-end

manufacturers use the more informative index of tensile and yield

strength, the best reference a buyer can look for when determining

bar strength and performance. Pound-test ratings for bars are

established in a static manner, with the bar supported under

the speciied load with no bouncing or dropping. An example of

this test might be a forklift with the forks set under the bar in a

grip width position, holding the bar loaded to 1500 pounds off A snap-ring sleeve assembly.

CrossFit Journal • Issue Sixty • August 2007

Where Barbells Come From

...continued

the ground for a speciied time. Upon unloading, if there is no

permanent distortion or bend, the bar is rated as a 1500 pound

test bar. A good 1500 pound test bar should be in the vicinity of

150,000 psi tensile and 130,000 psi yield strength. Again, though,

this is a static test, and is not appropriate for a bar that will be

used under dynamic loading conditions. If a manufacturer relies on

a pound-test rating and you want more information, ask about the

tensile and yield strength for the bar.

The manufacturing process

The irst step in the process of barbell manufacture is to cut

the bar stock to length. Once this is done, machining processes

are involved in nearly every production step. Machining involves

very expensive, technologically-advanced factory equipment that

removes metal from the raw piece. These processes are generally

time-consuming and skilled-labor-intensive. During the primary

machining process that a bar undergoes, raw bar stock is “turned”

or machined down to size. When it reaches the desired thickness,

it is checked for straightness to very low tolerances, and some

bars may need to be mechanically straightened in a press to meet

tolerance levels. The bar is also checked for other defects such as

cracks, pits, pots, and corrosion. Some manufacturers use X-ray

technology to check for internal abnormalities.

A sleeve is fitted to the bar shaft.

Creating the knurl—that rough, checkered surface that marries

the bar to your palms, ingers, shoulders, or back—is a slow,

complex, tedious process. Knurling is a pressing process; the knurl

is pressed, rather than cut, into the steel. There is no such thing as

a standard knurl. There are different markings for power bars than

for weightlifting bars, and different knurl depths to accommodate

gripping preferences, with knurls usually separated by smooth

unknurled spaces in the skin-contact areas of the bar. There are

many types of knurling patterns that vary with the intended

purpose of the bar, the most common variant being the presence

or absence of a center knurl, as well as the width of the smooth

unknurled center and the lateral extent of the knurl toward

the sleeve. Knurling coarseness is determined by the size of the

pattern—i.e. the size of each individual little square—and by the

depth of the pattern—shallow, medium, or deep. There are diverse

types of manufacturing equipment used for this process: scissor-

type knurlers, plunge systems, and traveling knurlers. Some knurls

are rolled after pressing to reduce the sharpness of the points,

and some are left sharp for greater friction against the hand. It is

a critical process and one that signiicantly affects the “feel” of the

bar in the hands of the lifter.

Bar shaft stock and finished bar shafts in the rack.

free. This type of steel is the best, but it is also the most expensive.

Stainless steel bars are rated for tensile and yield strength in the

same way as other steel bar stock, but the cost is two to four

times higher than that of regular steel. And since the harder steel

is more dificult and time-consuming to machine, stainless bars are

often prohibitively expensive.

The importance of the inish for the typical itness market is

mainly aesthetic. Fitness clubs generally prefer the brightness of

chrome or zinc. Others might prefer the longevity (but not the

cost) of stainless steel. The performance markets—athletics and

competition—hold a different view on the inish of a bar. Black

oxide is accepted as a good “tacky” grip for powerlifters. Zinc

or stainless may be preferred by weightlifters wanting a slightly

smoother grip. Chrome doesn’t hold chalk as well, but it cleans

more easily after use or when bloodied during a pull.

The inish—the coating or lack thereof—applied as a inal step

is the main factor controlling the appearance of the bar. Finishing

choices of chrome, zinc, or black oxide are available from most

manufacturers. Finish is usually applied in-house, though in some

cases it may be farmed out to a company that specializes in inishing.

Some manufacturers also offer stainless steel bars, which require

no inishing process and remain permanently rust- and corrosion-

CrossFit Journal - Issue 60.pdf

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