How much has technology been used to improve

sports shoes therefore enhancing the performance

of our Olympians? Before we investigate the type of footwear used by

our athletes let's examine a modern football boot. If

we look carefully we can see that it is made from a

variety of materials chosen because of their

individual properties.

Material Why used

Kevlar 10 times the strength of leather

Leather/canvas which is a composite

material This material is thin, stable and low density

Foam-blown polyurethane This gives a shoe extra cushioning

Thermoplastic polyurethane This makes a shoe both strong and pliable

Kangaroo leather Gives a footballer that extra spring in his or her

step. It offers goodelasticity

Question: Which one of the above materials is synthetic and from which natural source is it

derived?

Question: What exactly is a composite material? When two or more materials with very different properties are combined together they form a

composite material.

The different materials work together to produce a new material, which combines all of the properties

of the previously separate materials. Within the composite it is still possible to easily tell the different

materials apart. They do not tend to blend or dissolve into each other.

Composite Materials can be either man-made but they may also exist in

nature. Fibreglass and concrete are both composite materials. Car tyres, mud bricks and drinks

cartons are all made from composite materials.

Question: What does the terms stability, elasticity and density mean? Discuss the meaning of

the terms with your fellow students and then compare your answers to the ones below.

Stability This is a material's resistance to changes in shape and size.

Timber tends to 'warp' and 'twist' due to changes in humidity.

Plastics and metals deform when subjected to certain forces and stresses for long periods of time.

The extension of a material under a load over a period of time is called 'creeping'.

Aeroplane turbine blades are exposed to high temperatures and rotational speeds. It is important that

they are made from creep resistant materials.

Elasticity This is the ability of a material to bend and flex under the influence of a force and regain its normal

shape and size when the loads are removed. A product with good elastic properties is an elastic band.

Most structures like bridges or buildings need to have this quality to a certain extent. Buildings or

bridges without this quality would tend to collapse if exposed to high winds and extreme weather.

Density Density can be explained as the amount of matter in an object (mass) has per unit or space occupied

by the matter (volume). Relative density is the ratio of the density of a substance with that of pure

water at a temperature of 4 degrees centigrade.

Question: What is polyurethane?

Polyurethane is a unique material that offers the elasticity of rubber combined with

the toughness and durability of metal. The flexible type of polyurethane is used to make upholstery,

mattresses, earplugs, chemical-resistant coatings, specialty adhesives and sealants, and packaging. It

also comes to the rigid forms of insulation for buildings, water heaters, refrigerated transport, and

commercial and residential refrigeration.

What do the terms strength and pliability mean?

This term is used to describe a materials ability to resist force without breaking or permanently

bending. Different forces require different types of strengths to resist them. There are various types of

strength such as tensile strength, compression strength, shearing strength, Torsional

strength and bending strength.

Question: What is Kevlar? The Properties of KEVLAR®.

KEVLAR® is one of the most important manmade organic fibres ever developed. Because of its

unique combination of properties it is used today in a wide variety of industrial applications. The fibre

possesses a remarkable combination of properties that has led to its use in a variety of commercial

products since the 1970's

Fibres of KEVLAR® consist of long, interconnecting molecular chains produced from poly-

paraphenylene terephthalamide.

General Features of KEVLAR®: · High Tensile Strength at Low Weight

· Low Elongation to Break High Modulus (Structural Rigidity)

· Low Electrical Conductivity

· High Chemical Resistance

· Low Thermal Shrinkage

· High Toughness (Work-To-Break)

· Excellent Dimensional Stability

· High Cut Resistance

· Flame Resistant, Self-Extinguishing

Applications of KEVLAR

In the almost 40 years since its discovery, Kevlar has many applications: · Ropes that secure the airbags in the crucial landing apparatus of the Mars Pathfinder

· Small-diameter, lightweight ropes that hold 22,000 pounds and help moor the largest U.S. Navy

vessels

· Shrapnel-resistant shielding in jet aircraft engines that will protect passengers in case an explosion

occurs

· Run-flat tires that allow for greater safety because they won't ruin the rim when driving to the

nearest assistance

· Gloves that protect hands and fingers against cuts, slashes and other injuries that often occur in glass

and sheet metal factories

· Kayaks that provide better impact resistance with no extra weight

· Strong, lightweight skis, helmets and racquets that help lessen fatigue and boost exhilaration

A brief history of the sports shoe

Most of the teachers but probably not many of our students remember the rubber-soled plimsolls that

were traditionally worn in PE lessons throughout most schools in Europe. 'You could have any colour

you liked as long as it was black or white'.

These have been replaced by air cushioned, gel filled capsules with superior technical performance.

They come in a variety of colours, shapes and forms and are purchased as much for their appearance

as their performance.

The groundbreaking manufacturing technique that allowed the development of the plimsoll was called

vulcanisation, which is still used today. This process uses heat to meld rubber and cloth together.

Sulphur is used during the process.

Plimsolls were revolutionary at the time as they provided comfort, were lightweight and allowed the

user to move around silently. Plimsolls became known as sneakers and were sold on a mass scale by

the Keds Shoe Company in America as early as 1917.

Spike shoes

You may think that spiked running shoes are a

relatively new invention but they have been around

for at least a 100 years. In 1890's a British company,

which is now called Reebok created running shoes

with spikes in them. The spiked shoe was developed

out of necessity. The founder of the company enjoyed

running and wanted to develop a shoe that would

increase his speed.

In 1925 a company called Adi Dassler now known as

Adidas created a range of shoes with hand-forged

spikes. They offered a range of shoes for different

distances. The company used the strongest and

lightest materials available at the time to make the

running shoes.

Adi-Dassler who founded the company

Adidas, his brother Rudolph founded Puma.

The involvement of science and technology

In the 1970's sports shoe manufacturers employed experts to conduct research into how humans run.

They also investigated the shock effect to the body caused by the collision between the feet and the

ground. Their finding helped to develop new, improved sports shoes.

Their research found three types of running styles:

Neutral: This is where the heel of the runner makes contact with the ground

and the foot travels in a straight line as it moves forward.

Pronation: This where the heel hits the ground but this time the foot moves to

the side as it travels forward. It refers to the inward roll of the foot.

Supenation: This is where the heel hits the ground and the foot rolls outward.

Question: Have you ever examined the way in which you run? Ask a friend to watch you run

and ask them to decide which one of the above you are. It is worth finding out before buying

your next pair of trainers as most are tailored to suit either Neutral, Pronation or Supenation.

Question: What have become the most important aspects of modern running shoes? Discuss

these aspects in class or you may consider conducting research homework into this subject. Modern technological developments

In your answer to the previous question you may have discussed materials such as foam, silicon, air or

gel. These have been used to create cushioning systems in modern running shoes.

In the 1970's a plastic called 'ethylene vinyl acetate (EVA)' was developed. This material

revolutionised the construction of sports shoes. It was made up of tiny air bubbles that provide

cushioning and absorbs shock. This material is injection moulded into shapes, which serve as heel

supports.

To see a table of thermoplastics visit: http://www.design-technology.org/lesson4.htm

If you wish to find out more about injection moulding check out the following web page:

http://www.design-technology.org/injectionmoulding3.htm

A better grip

Following the introduction of Nike shoes, a technical breakthrough occurred in 1972 when Bill

Bowerman, while studying the pattern on a waffle iron, came up with a great idea -- waffle soles.

Bowerman then cooked some rubber in his waffle iron and glued it to the bottom of a pair of shoes,

which he later gave to athletes to test. The athletes came back with great reviews and the sneakers

were well received in the market. The patented outsole revolutionized running by offering better

traction in a lighter-weight, more durable shoe.

Nike Air: The air bubble

Nike's Air technology, which used a gas-filled bag of air inserted in the sole of the shoe to cushion the

impact of running, first appeared in 1979. The pair of sneakers was named; Tailwind and these

technologically advanced air-soles had provided a good foundation for which further Nike

advancements are based on. Since then, athletic shoes have become increasingly specialized and

prices for various sneakers have grown in accordance to the advances in technology and its value-

added features.

The basketball shoes below were sold in the 1980's and even included a pump valve. Customers were

encouraged to pump up their trainers as if they were bicycle tyres. Purchase of the trainers included a

pump.

Nike Air Pump (Pump details) Nike Air Pump (sole details)

Facts…

Did you know?

In 2003 American spent on average 50 dollars (£28) on a pair of sports shoes.

Companies sponsor most top athletes. This means that they are paid a fortune to wear the company's

products during a sporting competition.

The Olympics is the biggest sporting event in the world attracting worldwide television viewers. This

offers an ideal opportunity for sports companies to get their products seen.

Questions:

Different types of sporting events require differently designed sports shoes. Can you list a

number of track or field events and then attempt to describe the differences in the types of shoes

used for these events. You should be able to create specifications for each type of shoe.

You may consider borrowing a variety of sports shoes from the physical education department

in your school and conducting a full product analysis.

How about conducting this simple test. Ask two equally matched runners to race against one

another on a sports track. One of the runners uses spikes and the other uses ordinary trainers.

Interview the two runners after the race and write down their comments.

The runner with the spikes should feel that he had more grip on the track.

Sports shoe guide

The following table provides details about specific sports shoes. When viewing the table consider how

much trainer technology has advanced in the last 100 years.

High Jump

This type of shoe has a much

thicker sole. This gives

maximum support and

comfort.The shoe is light and

flexible which helps the

athlete achieve speed over a

short distance before

jumping.This shoe has to

have spikes. The spikes at the

front help the athlete to gain

speed in the run-up. The four

spikes t the heel provide grip

when the athlete takes off.

Javelin

This type of shoe has to be

robust and durable. Athletes

drag their feet along the

ground during the throw. As a

result the shoe has to be made

from a tough, hardwearing

material. Support is crucial.

Javelin shoes look more like

boots with protection around

the ankle. Most of them

feature strapping. This

prevents the foot from

moving in the shoe.

Jumps and pole vault

These events require speed

both on the ground and in the

air. In most cases straps have

replaced the laces. The sole

tends to be both firm and

flexible allowing extra

bounce in the jump. The

spikes are once again very

important. They provide the

grip before the jump.Notice

the spikes tend to be just at

the front of the shoe.

The Throws The shoe has to allow the

athlete to throw and spin. A

hooked strap over the toe

helps to prevent the feet from

moving sideways during the

build up to the throw.These

types of shoes do not have

spikes but have a hard sole.

This lengthens the lifespan of

the shoe.

The sole tends to have

circular grooves on the balls

of the feet. These help the

athlete to spin

Sprinting

This type of shoe has to be

lightweight and offer

flexibility at the front. They

all tend to have spikes, which

are located at the front. They

are able to cope with lots of

different types of surfaces.

Most Olympic Athletes have

their shoes specially made.

Long Distance

These shoes have to be both

durable and flexible. Comfort

is a real priority, also this

about the sweat factor.A mesh

is sometimes added in the

upper part of the shoe to

allow the foot to breathe. The

cushioning is also very

important.Spikes are

sometimes added but are not

essential.