Running is a great way to exercise if done properly.

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When initiating a running program, some of us simply aspire to improve our health and fitness level, while others strive to complete a marathon. Whatever the goal, running is a cheap form of exercise that embodies all the general benefits of exercise as well as cardiovascular support. It can be done nearly anywhere at any time. 

There are a few dangers to jumping in and hitting the pavement. The body needs to have time to adapt to the demands of running. The impact to the lower leg with each step is 2-3 times your body weight. This means if you are a 150 pound runner who goes out for a 3 mile run, you will be subjecting your legs to about 400 pounds of force for approximately 2,500 repetitions. This is a big jump in demand if you have not been running.

Thankfully, your body adapts quite quickly with regular training. Over time, the bones and muscles of the legs become stronger and able to withstand the forces placed upon them. Starting out too fast, too often or too far are the most common errors. What follows is a guide to avoiding these missteps while still getting out on the road to becoming a runner.

One of the most important factors in starting a program is running form. Your posture should be upright with the arms relaxed. The body should be held still with the arms and legs moving freely. The feet should stay pointed straight ahead with the knees bending so that the heels reach the height of the knees when observed from the side or back. Hands can stay relaxed as though holding on to a potato chip without breaking it. The legs should generally feel relaxed and freely moving as though you were riding downhill on a bicycle while keeping up with the pedals.

Excessive strain or pounding can suggest that you are pushing the intensity and speed too much, which leads us to our first of the common errors. Starting out too fast means running at a pace for which your body is not ready. If you're not sure about whether you are prepared, start with walking. As walking speed and distance become more comfortable, add a little running; about 1 minute, separated by 5 minutes of walking. Initially, only run (or walk/run) every other day for the first couple of months to help your legs get adapted to your new activity.

Running too often limits the amount of time available for your body to adapt and recover. Your body actually gets stronger and more resistant to injury when it's resting. During your rest days and at night during sleep your body builds the areas you worked to a stronger level. Think of it like this: While you work out, you are providing your body the plans and instructions it needs. Then, while quiet and at rest, it does the actual work. If your body is not finished working by the time you go out for your next run, you will limit how well it can adapt. This can actually cause injury and, if extreme, will result in the symptoms of overtraining.

Running too far too early in your running program also causes the body to be under too much demand and stress. To prevent this, start out with a mileage that you can do in 20-30 minutes (when you can sustain a run for that amount of time without stopping to walk). Once a week, run no more than 1 mile farther than your longest run. Add 1 mile each week. Every 4-5 weeks cut your longest run mileage in half, then start back where you were the previous week adding 1 mile once a week. If your desire is to run farther multiple times a week, again add miles 1 at a time, and do it slowly. In general, increase your mileage by no more than 10 percent per week to allow your body to adapt sufficiently.

Starting a running program is really pretty simple. Sustaining one safely and patiently is the tough part. Follow our simple suggestions and try out our sample program for training for a marathon. Who knows, you might just become a runner yet!