FROM JUSTIN KUO
Here's a nice measurement story that Steve Vaitones found.
By DEBBIE FETTERMAN / Special Contributor to The Dallas Morning News
Measuring a marathon course is a time-consuming effort that uses simple tools. Yet the ramifications of miscalculating a course are huge.
JIM MAHONEY / DMN
Pat Cheshier, who measured the White Rock Marathon's new half marathon course, examines the tools of the trade: a bike and a Jones Counter rigged to the front wheel.
View larger More photos Photo store
On Sunday, an estimated 17,000 runners participating in the Dallas White Rock Marathon, half marathon and relays will count on the precise calculations made by Pat Cheshier and Andy Beach, the half marathon and marathon course measurers, respectively.
Marathon director Marcus Grunewald can be assured that the courses are accurate because they've been certified by USA Track & Field state certifier, Tom McBrayer of Houston.
But that won't stop runners from questioning the course's length. Participants using global positioning systems often get inaccurate readings, attributed to runner error or signal obstruction, Grunewald said.
"For every e-mail I get that says the course was too long, I get another one saying the course was short," Grunewald said.
Certification ensures that participants cover the advertised distance. Times clocked on uncertified courses cannot be considered for records, rankings or qualification for events such as the Boston Marathon.
Despite the advent of GPS devices, road races are measured on a bicycle, using a USA Track & Field-approved Jones Counter, a steel measuring tape, notebook, calculator and pencil.
"It's the only way the USATF will take it," said Cheshier, 59, of Duncanville, who measured the event's new half marathon route.
The Jones Counter device was invented in 1971 by Alan Jones in an effort to measure a road race course. Before heading to college, Jones' son, Clain, sold 2,341 counters from 1973-1982, including four to the Montreal Olympics in 1976. There have been improvements, updates and name changes since, but the basic concept remains the same.
The Jones Counter mounts on a bicycle's front wheel and advances every time the bike moves four inches, said Beach, 50, of Garland.
Before and after covering a course, the bike must be calibrated four times along a precisely measured straight section of road to determine its average count. This number is used to calculate the counts per mile and per kilometer. Temperature changes, air pressure and air leakage from tires affect the calibration count, Beach said.
A course measurer is expected to measure the "shortest possible route" that a runner could take without being disqualified. That means riding diagonally between corners when crossing a street and straight through S-turns.
Beach said there's also a "short-course prevention factor" of 0.1 percent incorporated into the calibration procedure, which adds five meters to a 5K and approximately 42 meters to a marathon.
Once the cycling and calculating are completed twice, the data must be documented and a map created, Cheshier said. These materials are sent to McBrayer, the state certifier. A course certification lasts 10 years if there are no changes such as road construction or a new starting or finishing line.
Beach said he rides at an estimated 6 mph, stopping frequently to take notes. He prefers to ride during the middle of the night to minimize traffic concerns.
Cheshier prefers daylight, 9 a.m. to 3 p.m., acknowledging that traffic can be bad. His former police colleagues tell him he's "an accident waiting to happen."
Cheshier rides the course finish to start to compute his first measurement. Then he reverses course. If his numbers correlate within .08 percent (approximately 17 meters in a half marathon), he's set.
If not, he must measure the course again.
"If you're going to do it, do it right," Cheshier said.