Avoiding injury is crucial to any running program, whether you're a beginner or a seasoned pro. Many times runners start their training plan for a race and stop somewhere after halfway because they didn't take care of their bodies. Here are some ways to keep yourself injury free as you train for your next race, or even if you're just starting to get into running.

Run on trails

I can't stress this one enough. Running on asphalt and pavement is absolutely awful on your body. It's OK to run every now and again on these hard surfaces, but ideally you should try to run on trails or gravel roads as often as possible.

Buy good shoes

Good shoes that fit your feet are essential to your training. If your shoes don't fit, a myriad of things can go wrong with the rest of your body while training. You could get:

• blisters
• shin splints
• back problems
• knee problems

... and any number of other symptoms. Having shoes that fit your foot-type properly keep these injuries from happening.

Change the shoes often

Not only should you buy good shoes, you'll also need to change your shoes often. A good pair of running shoes should last you around 450 miles, so change them depending on your weekly mileage. If your feet start to get sore while running and other symptoms on the above list start to kick in, you might be due for a new pair of running shoes.

Stretch before you run

Stretching is another critical aspect of running that many beginners tend to overlook. Stretching keeps you relaxed during your runs and races, and improving flexibility helps your running form. Stretching also builds up muscle groups to help you avoid injury during running. So it's a good idea to find a stretching routine that not only helps build the muscle groups needed for running, but also builds the muscles that keep you injury free. I recommend this stretching routine for any runner. It's best to stretch after your muscles have warmed up a bit, so jog a mile and then do the stretching routine before you get to the "meat" of your workout.

It's a good idea to also stretch after your run as well to help keep your muscles loose. You might try stretching at different intervals in the day as another option.

Add core training

Strengthening your core muscles like abs can also be very effective for staying injury free. The stronger your core is, the more shock absorption you have every time you take a step. The core muscles cushion your back and spine, and also help you keep your form when you're tired.

About.com has a great article outlining what your core muscles are and how to strengthen them.

Don't overdo the training

No matter what your skill level, there is a tendency for people to overtrain. Whether you're a beginner or a pro, overtraining means the same thing: you're trying to run too much too fast. Make sure you only do what's on your schedule, no more. Overtraining is far worse than under-training.

Listen to your body

The best thing a runner can do to avoid injury is to listen to the body. If it's injured, it will tell you. (You can't miss it!) Your body knows when it's injured, and more often than not your body will tell you before it's injured. That's one of the great things about the human body: it can prevent you from becoming injured if you just listen and respond to what it's saying.

That said, there is a difference between "soreness" and "injury". Don't use soreness as an excuse not to do your scheduled training. There's nothing wrong with resting every now and again, but don't try to fool yourself into believing your soreness is an "injury".

Cross-train

Just because you're a runner doesn't mean you can't do other exercises on some days. In fact, most marathon training plans encourage cross-training at least one day a week. This allows you to use and strengthen the muscles that you don't really utilize while running. Here are some great cross-training activities:

• swimming
• cycling
• basketball
• rock climbing
• racquetball

The list could go on and on. Virtually anything that gets your blood pumping and quickens your breathing is going to be good for cross-training. Just try to stay away from activities that keep you from running on hard surfaces.

Injury is common in runners. However, it doesn't have to be. By taking care of your body and being smart about your training, you'll avoid injury.