The running shoe for you

What's the best running shoe for you? Marty Richardson outlines a myriad factors that should be taken into consideration.

During the past decade running shoes have become increasingly complex and specialised. Hundreds of different models are available, all with compelling advertising campaigns to entice you to buy them.

However, different foot types and running styles must be taken into consideration when choosing the right shoe to provide comfort and prevent injury.

See how you run

Everybody has a unique running 'action'. Approximately 50 per cent of the population have flat feet that tend to roll inwards (pronating), which causes strain on ankles, knees and hips. Twenty per cent of people have high arches and outward rolling feet (supinating) that can send a shock through the legs when running.

Take a look at your old running shoes and you will see a telltale pattern: If your sole is worn toward the inside and the upper is overhanging the sole, you're rolling inwards more than normal. This means your foot is flatter than average.

If all the wear is on the outside of the sole, and the upper bulges out that way, you have a supinating foot and don't roll in enough.

John-Paul Pelosi, from the Athlete's Foot store in Chatswood, Sydney, says most of the running shoes they sell are made for pronating feet, such as Asics or Brooks. Nike is also a popular brand, but is designed for the less common supinating foot.

"Generally Nike's have a high arch design. They are more flexible than Asics and provide a lot of cushioning," says Pelosi.

Shoe shape

A 'last', or mould, refers to the shape and construction of the shoe. Generally the upper is sewn together and glued directly to the sole (referred to as slip lasted). This promotes shoe flexibility, thus reducing stability.

In 'combination lasting', the rear of the upper is glued to a fibre board in order to promote stability, while the front of the shoe is slip lasted, maintaining forefoot flexibility. Flat feet generally need a shoe with a straight last. This will provide medial support to help decrease foot pronation. A curved shoe will not provide enough stability or control.

High arched runners can compensate their foot and leg motion with more curved and cushioned shoes. A supinated foot in a straight shoe will create lateral override on the shoe upper. In this instance the runner often complains that the shoe is too heavy, with excess weight medially (on the inside of the shoe).

Choosing an appropriate shoe model can help make your running 'action' more comfortable and efficient.

Cushioning

The body can experience shock through the legs that is equivalent to 2 to 4 times your body weight when you run. Therefore, shoes with good cushioning are vitally important for comfort and to protect against injury.

Better shoes have shock absorbing materials in the midsoles and heel and some have innovative technologies that are very effective. If you have high arches you will have the greatest need for cushioning.

External support features

External support features include a firm resistant heel counter, foot frame and variable lacing.

A firm heel counter will help increase rear foot stability and should be made of rigid, firm plastic.

For additional stability many shoes now feature a foot frame. This unit supports the upper and cradles the foot.

There are a number of lacing techniques available, which will help customise the fit of the shoe. Brands of shoes, which have recognised this, provide additional eyelets on the upper for variable lacing.

For runners that over pronate, most brands provide shoes with two-density midsoles. The firmer density is positioned on the medial side of the shoe to help reduce excessive rolling in of the foot.

Midsole

Probably the most important part of the shoe, the midsole is usually made from either EVA or polyurethane. EVA is soft, light and a good shock absorber but has poor durability. Polyurethane is harder and heavier, is also a good shock absorber and has good durability.

The midsole should not be too hard or too soft. Midsoles that are too soft contribute to excessive mobility. Runners requiring control of excessive motion should use a midsole of dual density that is harder on the medial (inside) aspect of the foot. Runners requiring extra shock absorption should choose a shoe with a soft midsole.

Flexibility

Before buying your running shoes, it is important to know whether you have a flexible foot or a rigid one. A way of doing this is to sit down, put your foot on a ruler and measure where your toes fall. Stand up on the ruler and if your feet have spread forward more than two centimetres you have a flexible foot. If there is no forward movement then you have a rigid foot. In general, flexible feet need more stable shoes and rigid feet need shoes with more cushioning.

For a comfortable fit

When you run, your feet elongate and spread upon impact. Long runs in warm weather can even make your feet expand up to a half size. Therefore, don't buy shoes that are too tight fitting (to allow for this expansion).For length, there should be a space the width of your thumb nail between the end of the shoe and the tip of your longest toe on your longer foot. Make sure you can wriggle your toes freely. The heel should feel snug, but comfortable.

Above all else, get your feet re-measured every time you buy new shoes since aging and injuries can change your foot size.

Summary of shoe features for different foot types