Sports: Understanding The Differences In Running Shoes

Understand the differences in the many kinds of running shoes available today. Learn why companies have so many different shoe designs.

Running shoe manufacturers design many different kinds of shoes to meet the requirements of variety of running methods and the needs of different kinds of runners. They also make shoes different for fashion and marketing reasons, but appearance ranks far behind comfort and performance for most runners.

Running 100 meters on a soft track is different than running a 26.2 kilometer marathon on hard asphalt roads. Running on a trail in the woods is different than running on a treadmill. Running during training can be different than running during races. So companies make shoes specifically designed for different surfaces, different distances, and different performance goals.

Each runner's body differs in its biomechanics. The forces of gravity and muscles act on bones and joints, affecting movement of the body. Height, weight, genetic skeletal structure, habitual posture, and injury history are among the factors contributing to a runner's biomechanics. Most differences in shoes address this wide variation in how human bodies work.

Shoes made for different kinds of running included trail shoes, racing flats, and road running shoes.

Trail shoes tend to weigh more than other running shoes since they have more heavily lugged soles, much like a hiking boot, for better traction. They usually have reinforced toes to protect the foot from rocks and roots and stumps. Some have specially designed heels to keep the foot stable on uneven terrain and prevent ankle injuries. Some have waterproofing. For trail shoes the need for protection outweighs the need for speed.

Racing flat design has the opposite goal. The need for speed is paramount. Thus the shoes are very lightweight, weighing about half of what a pair of trail running shoes weighs, or less. Their fit, if not quite like a glove, is much smoother than the fit of other running shoes. They offer less protection from impact forces since the light weight and smooth fit are achieved by removing some of the supportive sole cushioning and padding in the uppers.

Road running shoes greatly outnumber the other types. Compromise is the name of the game here, too, with comfort and protection from the repeated jarring of landing on a hard surface being the primary goals. Each shoe has multiple features, which, in combination, attempt to meet the needs and desires of a particular runner. Design factors that make shoes different include flexibility, durability, breathability, weight, cushioning quantity and location, foot positioning support, and lacing pattern.

Manufacturers, retail stores, and catalogs generally classify road running shoes in three groups: stability, motion control, and cushioned. These three groups correspond to three basic ways a runner's foot hits a surface and pushes off again on each foot strike: neutral (or normal pronation), overpronation, or underpronation.

In normal pronation the runner lands on the center of the heel and rolls through the foot with only a slight inward motion, toeing off with the weight distributed through the forefoot using all the toes, but with most of the force concentrated in the ball of the foot and big toe area. These runners usually have normal foot arches. Stability shoes are designed for these runners. They offer moderate pronation control to take some of the pressure off the ball of the foot.

With overpronation, a runner lands on the inside of the heel or quickly rolls to the inside. This runner typically toes off on the inside of the foot with almost all the weight concentrated on the ball of the foot and the big toe. People with flat feet often overpronate. Motion control shoes are built up on the inside edges to compensate for the overpronation. They hold the foot in a more neutral position to allow the force of impact to be distributed through more of the foot.

With underpronation (also known as supination), a runner lands on the outside of the heel and toes off with the outside of the foot. These runners often have high arches. Manufacturers recommend cushioned shoes for these runners. The cushioning offers protection from overall impact while allowing the feet to perform with their natural motion.

Within these three basic groups, there are many differences. Different manufacturers use different lasts, the forms on which shoes are built. Last shape determines shoe shape. Some shoes have wider toe boxes than others. Some have more rounded toe boxes. Some have wider or narrower heel cups. The shape and location of the indentations where your ankle bones and Achilles tendons fit varies across shoes.

Another way of classifying runner biomechanics that affects shoe design, besides pronation pattern, is by foot strike. While many runners do land on their heels and roll through their toes, other runners land with most of the force on their midfoot or their forefoot. Shoes for rearfoot strikers have built-up heels with a very thick sole in the rear of the shoe. Other shoe designs put more support and cushioning in the midfoot or forefoot for those who land there.

Shoes vary in flexibility, meaning how much a shoe bends on the heel-to-toe transition. They also vary in the stiffness or softness of the foot bed cushioning. Stiffer cushioning is made to support the weight of heavier runners. Shoes differ in their breathability, meaning how well the shoe upper lets air (and water) in and lets heat out. As with any outdoor activity, running outdoors comfortably requires being prepared for the elements. Highly breathable shoes serve well in hot weather, but lose their appeal in cold and wet conditions.

Confronted with so many choices, it's easy to be overwhelmed. But if you understand the significant differences in running activities and individual runners, you'll understand the differences in running shoes.

© High Speed Ventures 2011