I'm a great believer that each of us possesses a particular area of expertise. Some a little more eccentric than others, but a talent nonetheless.

I always wished my greatest aptitude would be something admirable, like superb running ability and an Olympic-marathon-trials-qualifying time. Instead, I was resigned to the fact that my talents were less enviable and more in line with how many grapes I could stuff in my mouth without choking, or a lifetime of races run with nary a negative split.

Nonetheless, I remained on the lookout for some type of talent that would set me above the crowd. I now proudly announce that after years of fruitless searching, I've arrived at my particular, albeit peculiar, area of expertise. Just call me the Matrix Man of Running Performance. Computation King.

I can tell you, off the top of my head, exactly how long it will take you to run a specific distance at a certain pace. I'm a walking, talking, running computer.

I could barely master algebra in ninth grade, but after years of studying pace charts and running-related calculators (reflecting one's times at various distances and paces), I've developed the skill to be a virtual time determiner.

Some may study a foreign language or how to increase their stock portfolio. I had much more important information to focus on. I studied interval pace calculators and finish-time predictor charts.

I, like many racing runners, became immersed in numbers of time, speed, length, splits, personal records and so on. Numbers help us stay motivated, challenged and inspired. We chase them, study them, memorize them, and are infatuated by them.

Determining times for specific distances, based on per-mile pace, was like kindergarten. Abacus stuff. I've advanced to post-graduate level, getting a doctorate in race-pace computation.

Determining your marathon time if you ran 8:23 per mile? I can spit out that answer in .6 seconds. Heck, I can calculate your total time if you tell me you anticipate running the first nine miles of the flat-terrain course in 8:15 per mile, there are rolling hills for the next 3.5 miles and you expect to slow down 10 seconds per mile, you plan a walking break for 345 yards at mile 15, and then will resume your initial pace plus eight seconds per mile for the next six miles, whereupon you take your customary potty break and aid-station refueling, then, with a resurgence of muscle activity and human spirit, you summon all energy to finish the remaining miles at an 8:12 pace.

I'll even supply your average pace including or excluding the porta-john stop and walking break, and further calculate how a 14.8-mph headwind for eight miles and 97-percent humidity would affect your time.

I'm ready for the Tonight Show, or at least a summer job as a carnival barker at running expos. I'm an ambulatory, talking data-processor of split times. An analytical engine of anticipated pace. And to think I was previously calculus-challenged.

With all my calculating abilities, I'm constructing a computation model of my own. Give me your age, average number of miles per week you've run during the last 14 weeks, number of running magazines you subscribe to, whether you ran track in high school, and, if so, your best two-mile time as a 17-year-old, how long you can hold a hamstring stretch, whether you refuel within 30 minutes of a run, number of races you've entered in the last six months, whether you do speedwork, whether you rotate your running shoes, and your best 10K where you didn't taper beforehand. Then I'll give you your anticipated race time from the 60-meter high hurdles to a 50-mile, rugged-terrain trail race. Heck, I might even be able to estimate your javelin throw within six feet or so.

Don't ask me about converting Celsius to Fahrenheit, or the speed of sound. I know my limits. But if it helps with your motivation to know how fast you should be able to run a mile based on your most-recent 8K, how many calories you burned during the latter, what your present body- mass index is, what pace you should do your easy runs at, and how that time correlates to a 21-miler on flat course, then I'm your calculating man.

Just give me a call. Though I might have to look up my phone number for you. I have a tough time remembering non-running numbers like that.

Excerpted by permission from "I Run, Therefore I Am -- Nuts!" by Bob Schwartz. Copyright (c) 2001 by Human Kinetics MRPublishers, Inc. Available at bookstores, Amazon.com, humankinetics.com or 1-800-747-4457. MR