Are GPS Watches More Accurate Than Half-Marathon Course Measurements?
When it comes to running races, particularly half-marathons, the accuracy of GPS watches can be a source of frustration for many runners. Even when following the same course as a measured course, discrepancies can arise. This article will delve into the accuracy of GPS watches when compared to half-marathon course measurements and explore the measures taken to ensure accurate course measurements in certified events.
The Imperfections of GPS Watches
GPS watches and apps are not without their flaws. They are designed for everyday use and are not always as precise as one might think. However, it is worth noting that these tools can still be quite reliable under certain conditions. For instance, professional athletes might achieve shorter times on the same course compared to other runners due to less interference and a more direct path.
What about Certified Courses?
Courses that are USATF (United States Athletic Federation) certified are held to stringent standards. These courses are measured using bicycles equipped with Jones-Oerth counters calibrated on the day of measurement. This method is as accurate as one can get, akin to using a giant tape measure to measure the course. The course is measured at least twice, and the two measurements must agree to within 0.1%.
The process of USATF certification is detailed in a 66-page manual, ensuring that every aspect of the course measurement is carefully considered. The certification process also involves surveying professionals who find the shortest possible path runners can take, including using 'tangent lines' to minimize the distance covered.
Why USATF Takes Accuracy Seriously
USATF is concerned with maintaining accurate race records. If a course is found to be shorter than the certified distance by even a fraction, the race results could be invalidated. This is why USATF tends to err on the side of caution and measure the course slightly longer. The official course length will be the shortest of their official measurements to ensure it meets the minimum requirements for an official record.
Running Technique and Course Length
For those who care deeply about their race times, there are strategies to optimize the course length. Running professionals who survey the course beforehand can determine the shortest path. By running early in the race and staying at the front, runners can follow this precise route, potentially achieving a more accurate course time. However, for the average runner who gets caught up in the pace of the pack, the course might seem slightly longer.
Conclusion
While GPS watches are not infallible, their inaccuracies are often exaggerated. Half-marathon courses that are USATF certified undergo rigorous and meticulous measurements to ensure accuracy. Those who truly care about their race results can take steps to optimize their course length, but it's important to understand that official race distances are measured with great care to maintain fairness and accuracy in record-keeping.