The right shoe for walking and running

Walking and running are the most accessible types of exercise; the only equipment you really need is a good pair of shoes. But not just any footwear will do.

"While walking and running share similar movements, how your foot is supported differs, which is why most walking and running shoes are designed differently," says Dr. Adam Tenforde, director of the Running Medicine Program at Harvard-affiliated Spaulding Rehabilitation Hospital.

Taking steps

Walking involves less stress on the feet than running, absorbing about 1.5 times a person's body weight with each step compared with three times for running. When walking, your heels hit the ground first before your foot rolls forward to begin the next step. Because of this rolling motion, walking shoes are designed to have soft, flexible soles, which help you push off with each step. Also, because the heel strikes the ground first when you walk, walking shoes have an angled heel to absorb most of the shock and reduce pressure on the ankles.

In comparison, runner's feet strike anywhere from the heel to the midfoot or forefoot. Therefore, running shoes are designed to have thicker soles that act as shock absorbers. They are also lighter than walking shoes to help with fatigue over longer distances. "Because of these differences, ideally running shoes can be used for walking, but you should not run in walking shoes," says Dr. Tenforde.

Proper protection

The right shoe for your activity can help you avoid foot and ankle pain. For example, plantar fasciitis, also known as heel pain, is caused by inflammation of the fibrous band of tissue on the bottom of the foot. Achilles tendinitis—inflammation of the tendon connecting the calf muscle to the heel—causes pain above the heel or along the back of the leg.

Proper footwear can also protect against knee pain. "Footwear can contribute to changes in your mechanics and some shoes may cause pain suggesting these shoes place extra stress on your knees," says Dr. Tenforde.

Remember that while the right shoes can protect against pain and injury, they can't fix existing problems. "If you have any type of foot pain or impairment that makes walking or running uncomfortable, consult a physician or physical therapist to properly address the issue," says Dr. Tenforde. "Changing shoes won't help."

Get fitted

Because feet come in so many shapes and sizes, it's impossible to recommend a specific walking or running shoe that suits everyone. (Some people, though, may benefit from minimalist shoes; see "The big impact of minimalist shoes" below.) Still, you should follow some basic guidelines for shoe shopping and wearing. For example:

• Visit a specialty running store, as it will offer a variety of styles and have hands-on fitting experts.
• Have your arch and gait evaluated to find out whether your foot rolls inward (pronation), rolls outward (supination), or stays neutral. Many running stores provide this service.
• Feet tend to expand during the day, so shop in the early evening when your feet are at their largest.
• Bring your own socks. The thickness of your socks will affect how your shoes fit, so wear ones you like when trying on shoes. (When walking or running always wear synthetic or cotton-synthetic blends to wick away moisture.)
• Your athletic shoes will usually need to be a half-size larger than your regular shoes to accommodate any swelling during activity.
• Bring along any orthotics or other shoe inserts you usually use. Many shoe brands do not accommodate them, so you may need to go up an additional half-size.
• Feet naturally widen with age, so make sure your shoes have adequate width: Remove the shoe's insole and step on it. If your foot goes over the edges, the shoe is too narrow.
• There should be some wiggle room in the toe box. You should have about a half-inch (or one finger's width) between your longest toe and the front of the shoe.
• Test a shoe's flexibility. Grab the toe and heel of a shoe and pull them toward each other. The shoe should bend easily at the ball of the foot. Flexibility offers a greater range of motion and an easier push-off.
• Shoes should feel right when you step into them and not need to be "broken in."
• Experts recommend replacing shoes every 300 to 500 miles. Walking or running for 30 minutes daily, five days a week, translates to a new pair every six to 12 months.

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