How do I start a running regimen?

Erica Loder is a physical therapist with Providence Sports Care Center in Portland, Ore. A certified athletic trainer and certified strength and conditioning specialist, she has been with Providence since 2004. Loder, who was a distance runner for three years and is currently a competitive cyclist, speaks about running safely from both a personal and professional perspective.

How should you get started?

If you've been sedentary or have a pre-existing medical condition, it's important to see your health care provider before starting a new exercise program. Start first with walking to condition your heart and lungs. If you have a significant amount of weight to lose, begin with low-impact exercise and strength training to condition your body for the specific stresses of running and to prevent injury.

Once your body is ready to run, start slowly: add a few minutes of running into your walk, gradually increasing the minutes you run each week. Consider these three variables when increasing your activity level: how often you run; how hard you run; and how long you run.

How do you select shoes?

Most athletic shoe stores can perform a basic gait analysis to help you select the proper running shoe. The right shoe will provide enough support without being too stiff. Not enough support, known as under-correction, and too much structure, known as overcorrection, both can lead to injury by preventing the correct mechanics from occurring during running.

What are the most common running injuries?

"Overuse" injuries can occur around your kneecap, on the outside of your knee, on the bottom of your heel and in the tendon of your calf. Shin splints, which cause pain along your shin, and stress fractures, which usually occur in your foot or lower leg, also are common. You can decrease your risk of injury with proper training, good shoes and taking a day off in between runs.

If you have pain, should you take a break?

If you begin to experience pain, seek advice from a sports medicine professional as soon as you can, rather than trying to train through it on your own. A professional can help you manage the situation safely, prevent it from getting worse and return you to your training as quickly as possible.

Should you stretch before or after a run?

Rather than doing a pre-run stretch, engaging in a dynamic warm-up can help improve performance. A dynamic warm-up involves continuous movement, which helps to warm up the muscles and increase blood flow. It also enhances coordination and motor ability while revving up the nervous system. Some examples of dynamic warm-up exercises include a slow jog, straight-leg kicks, a high-knee walk, swinging your arms back and forth or in circles, and walking backwards. Stretching after a run, rather than before, also can help prevent injuries.

Who can run barefoot?

Barefoot running is a hot, and also somewhat sensitive, topic within the running and medical communities. Running without shoes forces you to run on your mid- to forefoot, which decreases the impact by lessening the braking force from your heel striking the ground. The ability to run barefoot without injury is largely based on foot structure, body weight and running mechanics. The small muscles in the feet and lower legs must have enough strength and endurance to support the repetitive impact of running. The more a person weighs, the greater the impact. If your body weight is more than your feet are able to handle without the support of shoes, you are likely to injure yourself.