When you get right down to it, running is not about being comfortable; it's about pushing limits. Once you have been running for a while, to stay engaged in the repetitive act of putting one foot in front of the other, you have to challenge yourself. One such challenge is to run faster. This quest for speed is why so many running schedules contain a variety of runs. The long, slow run for endurance mixed with interval and tempo workouts for speed.

A tempo run is exciting and a little nerve-wracking because the goal is to work outside of your comfort zone, but at a steady pace unlike intervals where periods of pushing yourself hard are followed by a period of recovery. The one advantage of the tempo run is that it is short. This decrease in time hopefully makes up for the increase in sustained intensity. A tempo run is not sprinting, but as ultra marathoner Dean Karnazes puts it " running comfortably hard." I know that sounds like an oxymoron, but trying to find that comfortable, yet hard pace will force you to challenge yourself while listening to your body. Experiment until you find a pace you can sustain without beginning to struggle.

To see what your first tempo run should look like, just read more.

You should aim to do a tempo run every seven to ten days. As you progress, keep this simple formula, but add a couple minutes to the tempo run portion of your workout.

Here are a few more parameters Runner's World offers for figuring out your tempo run pace:

• Recent Race: Add 30 to 40 seconds to your current 5-K pace or 15 to 20 seconds to your 10-K pace.
• Heart Rate: 85 to 90 percent of your maximum heart rate.
• Perceived Exertion: An 8 on a 1-to-10 scale (a comfortable effort would be a 5; racing would be close to a 10).
• Talk Test: A question like "Pace OK?" should be possible, but conversation won't be.

Now tell me when are you going to try your first tempo run? Speed work is not meant for beginning runners, but runners with a solid base of fitness looking to improve their fitness level.

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