The 5-K is the most popular race distance in America, the logical first race distance for most recreational runners, and a distance considered critically important even by Olympic marathoners. What more could you ask for from a race?

You can barely turn around without bumping into a 5-K these days. You can find 5-Ks all year long in almost every town and city. There are Mother's Day 5-Ks and Father's Day 5-Ks, Firecracker 5-Ks (on July 4th) and Thanksgiving 5-Ks, Jingle Bell 5-Ks and Super Bowl 5-Ks, Breakfast 5-Ks and Midnight 5-Ks.

The race's appeal is easy to understand: It's short enough--3 miles, plus 188 yards--for beginners and recreational runners, and challenging enough for the world's best. Anyone running a few days a week can finish a 5-K right now, without any additional training.

The vast majority of 5-K runners are looking for a personal challenge and improved health and fitness. As your 5-K fitness improves, so will your times in longer races. That's why Olympic marathoners stay sharp with 5-K training and racing.

Here are the 10 essential training principles that you need to follow for your first (or your fastest) 5-K.

1. Run 3 Or More Days A Week
New Jersey coach Bob Gordon believes that beginning runners can get by on 3 training days per week. The higher your goals, the more training days you should log. If you race a 5-K and find yourself fading during the last mile, there are two likely explanations: You went out too fast; or you lacked endurance because you hadn't done enough days of consistent training. To cure the first, you have to start slower and race smarter the next time. To eliminate the second, simply get with the program. (See Sidebar: "A Plan for Every Pace" for a 5-K training program for runners who want to run anywhere from 5 to 12 minutes per mile.)

2. Include A Weekly Long Run
Champion masters runner Janice Ettle recommends one long run every week. Intermediate and advanced runners should build up to 8 miles or more. Beginners will obviously do less. A realistic long-run goal for a first-time 5-K runner: 4 miles. Do your long runs at a slow and comfortable pace. If necessary, take a 1-minute walking break every mile.

3. Increase Your Mileage
Even though the 5-K is the shortest of the popular road-race distances, you still need adequate mileage to run it well. We suggest a bare minimum of 8 miles a week. "Some runners make the mistake of concentrating only on speed, and neglecting their endurance," says Gordon. "But you need to keep your mileage up." If you neglect mileage, you begin to lose your aerobic base, and the 5-K is a mostly aerobic distance.

4. Build Up Gradually
Coach Bob Williams of Portland, Oreg., tells his runners that they need to be patient and increase their training on a slow-but-sure schedule. Rome wasn't built in a day. Same goes for distance runners. "No matter what your age or ability level, training for the 5-K requires gradual adaptation," says Williams. "You'll be most successful when you avoid burning yourself out." One time-honored rule: Increase your weekly mileage by no more than 10 percent per week.

5. Do Tempo Runs
On tempo runs, you run faster than your everyday pace for 15 to 30 minutes. Most coaches describe the effort level as "comfortably hard." Tempo runs increase your speed and endurance, and accustom you to pushing yourself more than normal in your training. Williams suggests that you start with 15-minute tempo runs, and work up to 25 or 30 minutes. For beginning runners, he advises a pace that's 30 to 35 seconds per mile slower than 5-K race pace. As you gain strength, the pace can get faster: to 20 to 30 seconds per mile slower than 5-K pace. If you don't know your 5-K pace, follow the "comfortably hard" guideline. You'll quickly hone in on the effort that works for you.

6. Or Try "Mini-Tempo Runs"
Some runners find it simpler to do 1-mile repeats--what we might call "mini-tempo runs" because they're shorter than traditional tempo runs, and you get recovery breaks between them. Also, many runners like the security and exactness of a track or measured course. But don't try to run these 1-milers hard and fast. It's important to follow the basic rule of tempo running: Run at a pace that is 20 to 30 seconds per mile slower than your 5-K race pace. Run two to four mini-tempos in a workout, with a 3-minute jog between them.

7. Switch on The Speed
Building your mileage and doing tempo runs are the keys to your success. But at some point, you'll also want to add a little speedwork. The classic speed workout is "quarters," which used to be quarter miles (or 440 yards), but is now usually 400 meters. Coach Roy Benson in Atlanta has his beginning runners do quarters at a pace 20- to 30-seconds per mile faster than their normal 5-K race pace. In other words, if you can race a 5-K at 8-minutes per mile (2:00 per quarter), you would run these laps at about 7:40 pace, or 1:55 per quarter.

8. Run Pickups
An even easier form of speedwork is pickups on the grass or roads. In a pickup, you gradually accelerate to a hard pace (but not all-out), and then hold that pace for just 10 to 20 seconds. After the pickup, you return to your normal relaxed pace for 2 to 4 minutes, then do another pickup. A simple speed workout of this kind might include four pickups. As you get stronger and more confident, add more pickups in a gradual manner: five, six, seven, eight.

9. Vary Your Speed Distances
Bob Schul won the Olympic 5000 meters in 1964, and now coaches runners in Dayton, Ohio. He comes from a school of training where the precision of the training is less important than the "feel" you develop while running speedwork. His runners do some of their speed training quite easy, and some of it quite hard. More important, they vary their distances. They don't just run quarters all the time. They'll run 800s, 400s, 200s, and even shorter distances. A favorite Schul workout: fast 150-meter repeats with 50 meters of walking between repeats.

10. Run Negative Splits
This approach is used most frequently in the marathon, but it also applies to speedwork and other races. The idea: to finish the race or workout faster than you started it. Research and real-life experience have shown that the negative-splits approach leads to the best distance-running results.

Williams advises his runners to run negative-splits workouts on the track. For example, you might run four 400-meter repeats in 2:00, 1:57, 1:54, and 1:50. Williams likes the way the negative-splits approach teaches you to get faster as you're getting more fatigued. "That's the way races go, after all," he notes. "You get a little more uncomfortable with each passing mile."

An added benefit of negative-splits training and races: In races, you'll catch a lot of other runners in the last mile. Ah, the sweetness of a well-run 5-K.