Proper running form is just as important for long-distance runners as it is for those doing the 100-meter dash. While poor form can cost sprinters the fractions of seconds needed to win, sloppy long distance form will quickly fatigue runners and cause them to expend unnecessary energy. Hunched shoulders and improper strides can even lead to injuries in the long-term for distance runners. Read below for suggestions on how to hold and move your body for multiple miles.1. Lessen the Impact
One of the distinct differences between short and long distance running is the way in which your legs propel you from one step to the next. Sprinters pound the pavement in quick short steps, with their calves absorbing a great deal of the impact. They can afford to do so, though, because their races are short enough that the short, intense steps won't cause injury. Long-distance runners have a much different challenge. The volume of steps they'll be taking on a given run doesn't allow them to hit the ground with such speed and force. Rather than letting calves take much of the impact, long distance runners should open up their stride. The step should feel like much more of a full glide, rather than an abrupt burst, with your calves and quads working together to push the body forward.2. Strengthen and Stretch
On the days you're not running, do exercises that will build up the various leg muscles supporting your stride. Squats will build your quads and good, solid lunges will shape your calves and promote flexibility, as the exercise requires you to stretch one leg in front of you as far as possible, while keeping the other stretched behind you and dropping your knee down low. Doing legwork at a fast, aerobic pace or to music will also enhance your agility as it strengthens the muscles.3. Practice Posture
Building up your back, shoulder and chest muscles will help you keep proper posture and support your upper body during the long runs. It can be easy to slouch when the rest of your body is fatigued, but slumping your shoulders during a distance run will tire you at a much faster rate than a strong and upright back will. Alongside your running routine, be sure to do push-ups and other exercises to strengthen your upper body. The tightly aligned form required in a push-up will translate well to running. Practice your posture throughout the day by keeping a super straight back while sitting at your desk for work.4. Carve Your Core and Arms
Strong abs will support your back and keep your body balanced as you're gliding forward. Do a few sets of crunches a week after your runs, but be conscious not to strain your neck and shoulders. Be sure to keep strong, deliberate arms while running. Do what feels most comfortable, but keeping your forearms at about a 90-degree angle to your upper arms, with elbows slightly bent, is a good template. Swinging arms straight in front of you will add speed, while swinging arms across the core will help maintain balance for your running form.