Any marathon will have those who are listed in the results as DNF —- started but did not finish. Many of these are first timers, those who discover, somewhere along the 26.2 miles, that what they know about the marathon is not enough to get them to the finish line.

That’s understandable. Running a marathon is a formidable physical and mental challenge and for beginners, a journey into the unknown.

But this year my name also appeared in the DNF list of the Pittsburgh Marathon. My DNF resulted not from knowing too little, but knowing too much.

After training and completing 14 marathons, I know what to expect —- the excitement and holding back in the beginning miles, the steady effort of the middle, then the gradually increasing fatigue requiring focus to the finish. So when I felt overheated, fatigued and weak after only ten miles, I began to worry.

My anxiety was fueled by knowledge that any large marathon, along with the DNFs for muscle cramps, sprained ankles and dehydration, there is the statistical probability that someone will suffer a life threatening heart attack.

Although even young athletes like Ryan Hall can suffer cardiac death due to heart deformities, those in my demographic, the over-40s, succumb to heart attack from coronary artery disease.

The fear of winning the unfortunate lottery of being the one in 100,000 marathoners to suffer a heart attack on the course was enough to steer me to a medical station at mile 12. (I’ve had apparently healthy friends and family who’ve suffered heart attacks with minimal symptoms.)

Aids at the medical station ran through their checklist while checking my heart and blood pressure. Since my only symptom was, “I don’t feel right,” they offered some sort of liniment for my cramping legs or a ride to the finish line in an ambulance —- after the race.

I pictured my friends and family frantically trying to locate me at the finish line after five or six hours while I napped in the back of an ambulance. I decided to move on with no real plan except to get closer to the finish line.

I walked and ran to the next relay station at 15 miles where I decided against continuing on an agonizing five-hour marathon pace.

I officially dropped out of the race at the medical station and wrapped in a mylar blanket for the ride to the Northshore. Waiting for the shuttle bus I felt alternately dizzy, flushed and slightly nauseous and wondered if these were signs of some mysterious ailment or simply symptoms of disappointment.

Attendants at the finish line medical tent took vital signs and forced me to drink fluids. I was somewhat embarrassed to take up space and attention when my only symptoms seemed to be that ten miles didn’t seem like ten miles.

Around me others were prone and pale, hooked to I.V.s or packed in ice. I was released to my family after downing three cups of water and promising to follow up with my doctor.

My family doctor, though not a runner, has resigned himself to the fact that I will always be one. And he continues to advise me in a way that makes that physically possible. He listened, asked questions and made notes, taking seriously my vague notions that something just didn’t feel right, then sent me for a few tests before making a diagnosis of simple dehydration.

As I recalled the days leading to the marathon, the diagnosis began to make sense. I’d spent days attending to last minute details of a marathon charity effort and nights mopping up my house after the week’s deluge of rain.

By marathon morning, I was stressed, sleep deprived and certainly under-hydrated.

It’s been said that you learn more from failure than success. As I learned from this year’s Pittsburgh Marathon, it’s not what you know, but how you apply that knowledge that makes the difference between a finisher’s medal and a DNF.

Upcoming eventsSaturday, 8:30 a.m.: Cecil Jarvis Greater Clarksburg 10K, Clarksburg, WV. Also KidsK for ages 12 and under and 2-mile fun walk at 10 a.m. 304-624-4100 or www.greaterclarksburg10k.orgSaturday, Chardonnay 5K, Mercer. Starts at 724-662-1910 or coolspringsfitness.com.Saturday, 9 a.m.: Dayspring Harvest 5K Race/ 2 Mile Walk, Ellwood City. 724-752-1600 or johantinossi@gmail.comSaturday, 10 a.m.: Veverka’s Valor 5K Run/ Walk, Hermitage. Benefits scholarships to Mercer and Crawford county seniors. 724-628-9544 or Sandra.soliday@gmail.orgSunday, 8 a.m.: Father’s Day 5K/ 10K Run/Walk, Pittsburgh. Starts at Riverfront Park outside Heinz Field. 412-572-6830 or www.fathersday5k.comJune 21, 7 p.m.: Quality Life Cup Series 5K, Sarver. Cash prizes. 724-431-0770 or www.qualitylifeservices.com.June 22, 7 p.m.: Strawberry Days 5K, Grove City. First in Mercer County Twilight Quad. 814-678-4226June 25, 9 a.m.: Butler Road Race, Butler. Choice of 5 miles or 2K benefits scholarship for local athletes. 724-282-7977 or butlerroadrace.orgJune 26, 8:30 a.m.: Run for the Hills 10K, Willoughby, OH. 440-946-8705 or online registration at www.active.com.July 2, 9 a.m.: Heritage Day 5K, Greenville. 724-589-2086July 2, 9 a.m.: Ellwood City Ledger 10K, Ellwood City. Starts at Ewing Park, 31st year for this classic race. 724-752-1583 or www.smileymiles.comJuly 2, 9 a.m.: Ford City Heritage Days 5K, Ford City. Flat and fast through downtown. 724-763-3986 or jsolak@iup.eduJuly 4, 8:30 a.m.: Race for Virginia and Friends 5K, Cranberry Township. Popular race with good post race food and random drawing prizes starts in Cranberry Community Park. 724-772-7429 or bmarkovich@zoominternet.netJuly 6, 7 p.m.: Community Center 5K Run/ 2 Mile Walk, Punxsutawney. Unique Punxsy Phil awards. 814-938-1008 or punxsyacenter@gmail.comJuly 9, 8 a.m.: Cross Country Crusade 5K, Saxonburg. Run on Knoch High School cross country course. First in Saxonburg Distance Series. 724-586-6941 or mlkletzli@embarqemail.comJuly 9, 8 a.m.: Sandy Lake Fireman’s Fun Days 5K, Sandy Lake. 724-376-2714 or slvfdsecretary@yahoo.comJuly 9, 9 a.m.: Emlenton Festival Duathlon, Emlenton. Run 5K, bike 10.5 miles starting at Hughes Park. 724-867-6881 or smorrison@central.coopJuly 10, 7:30 a.m.: Trailblazwer 15K and 5K, Meadville. Out-and-back on paved Ernst Trail. Ziegler4@zoominternet.netJuly 10, 6 p.m.: Hoodlebug 5K Run and Fun Walk, Homer City. 724-541-0013 or fulmer_ed@yahoo.comJuly 13, 7 p.m.: Fredonia Fireman’s 5K, Fredonia. Out-and-back with gradual downhill finish. Second race in Mercer County Twilight QUAD. 724-866-1374 or smc@runhigh.comJuly 17, 7:30 a.m.: Presque Isle Half Marathon, Erie. Run on Presque Isle State Park peninsula. 814-881-0060 or davecomi@erie-runnersclub.org

Race resultsRun Like an Animal 5K, May 4: Andrew Brosius, 1st Overall M, 17:14; Gianna Guerino, 1st Overall W, 19:12; Mitch Radella, 3rd 40-49 M, 19:36; Clint Hartle, 22:00; Ron Hartle, 22:45ACMH Hospital Rocky’s 5K, May 14: Ean King, 1st Overall M, 17:26; Brian Forester, 2nd Overall M, 18:30; Tim Monfre, 3rd Overall M, 18:54; Lindsay Nemec, 1st Overall W, 22:47; Kelly Check, 2nd Overall W, 22:49; Kody Flanders, 1st 25-29 M, 19:33; Mitch Radella, 1st 45-49 M, 20:07; Brian Cochran, 1st 40-44 M, 20:36; Matthew Grafton, 2nd 16-19 M, 21:31; Nick Kijowski, 2nd 45-49 M, 24:42; Stacey Bowen, 2nd 35-39 W, 26:11; Susan Gress, 1st 40-44 W, 28:18; Julie Opalka, 1st 50-54 W, 28:48; Elizabeth Green, 1st 60-64 W, 31:34; Ariana Clark, 1st 10 & Under W, 31:34; Spencer Clark, 1st 35-39 M, 31:35; Kayla Check, 3rd 10 & Under W, 42:32; Mandy Knappenberger, 2nd 55-59 W, 47:39; Janelle Claypoole, 28:09; Seth Grafton, 28:31; Al Lane, 33:08; Brennan Grafton, 34:03; Patty Grafton, 36:28; Kevin Check, 42:34; Brian Kepple, 43:49; Melissa Lorigan, 44:20; Carrie Rodgers, 46:38; Cameron Toy, 47:22; Sarah Grafton, 48:57; Patrick Lane, 49:29; Rita Lane, 49:35; Spencer Toy, 51:53; Greg Toy, 51:56; Josh Trudgen, 54:55; Teresa Hollobaugh, 55:17; Melissa Lichanec, 55:18; Mindy McClister, 57:27Riverview 5K, June 10: Charlie Ban, 1st Overall M, 16:48; Natalie Iacovoni, 1st Overall W, 21:05; Ann Gagliardi, 3rd Overall W, 22:07; Timothy Wyant, 2nd 40-44 M, 19:11; Mary Ann Meeder, 3rd 55-59 W, 52:32Bob Cunningham, 22:03; Christopher Federowicz, 24:20; Sampson Wyant, 28:40; Gary Golebiewski, 30:42; Lindsay Daprile, 35:15; Jordan Meeder, 41:20

Pat Neubert is a running columnist for the Butler Eagle