Although many athletes train the entire body with equal intensity and use heavy weights for their legs, heavy strength training for the legs is not necessarily vital or helpful for the long-distance runner. Elite athletes and advanced competitive runners engage in strength training that emphasizes the upper body during their training. Following their example, go easy on the legs, using strength training cautiously (using low weights with a high number of repetitions) while emphasizing upper body work.

As some runners age, they find that more lower extremity exercises are helpful. Some of them have then generalized that if these are good for the aging athlete, they are good for the younger one, too. That is not necessarily so.

Younger athletes aren't losing muscle by 5 to 20 percent; they are still in their prime. Young runners are probably better off performing only a light lower extremity workout in combination with different running techniques to enhance their running speed, form, and strength. Such techniques include fartlek workouts, hill repeats, striders, tempo runs, and repeat intervals.

Of course, there is value to gentle leg extensions, leg presses, leg curls, straight leg lifts, and (sometimes) gentle calf raises, as well as crunches. Just don't go overboard on the muscles that runners exercise the most.

Since you're going to be working muscles you might not have known you even had, the following is a brief anatomy lesson to help you both identify and appreciate your muscles. Knowing where the muscles are located and what they do enables you to understand what you're working out and why.

Shoulders, Back, and Chest

A variety of muscles work together in your shoulders, back, and chest. The muscles that traverse your chest below your breasts are called pectorals but are commonly referred to as pecs. Stretching along the tops of your arms near your shoulders are your deltoids. Nearby are your rotator cuffs, a group of four muscles under your shoulder that are used for carrying, catching, and throwing. The trapezius is a diamond-shaped muscle that runs across the shoulders, toward the neck, and into the lower back.

In your back, you'll find the erector spinae, the muscles that run the length of the spine and that flex to straighten, bend, sit, stand, and lie down. Also running down your back is the latissimus dorsi, a large muscle that goes from below your shoulder to your lower back. In the center of your back are triangular-shaped muscles known as rhomboids, which keep the shoulder blades together and assist in proper posture.

Arms and Abs

The muscles of your arms and midsection are also important. In your arms, the biceps are the muscles on the front of your arm, the ones you flex when someone asks to see how strong you are. The companion muscles to the biceps are the triceps. These are located on the back of your upper arm.

On the midsection, you will find your obliques and rectus abdominis. There are internal and external obliques that line both sides of your midsection and support the rectus abdominis. Meanwhile, rectus abdominis muscles extend from below the chest to just below the navel. They are more commonly referred to as abs.

Hips, Butt, and Legs

Essential to runners, the major lower body muscles are the gluteus maximus, gluteus medius, and gluteus minimus, all of which are commonly called gluts. Other lower body muscles include the hamstrings (a group of three muscles at the back of the thigh) and the quadriceps (a group of four muscles on the front of the thigh).

You should also be aware of the tibialis anterior, a group of muscles that extends along your tibia (the bone that goes from your knee to your ankle, along the shin).

Our muscles: front view

Our muscles: back view