At a local half marathon last year, they gave awards for the oldest age groups first. When a 68-year-old runner's time was announced as being faster than 1:30, a twenty-something male's voice sang out over the crowd, "Whoa! Guess we know who kicked our butts in age grading!"
This young runner knew about age grading, a way to level the field by adjusting for age (that made the masters' time equivalent to under 1:07 if he were in his 20s)—do you?
Age grading is a method that applies a formula to each runner's actual time to account for slowing due to age factors. Every few years, statistical wizards Ken Jones and Alan Young pour over records from races all over the world and update the age-grading tables under the auspices of USATF Masters Long Distance Running and World Masters Athletics.
Jones and Young identify the best times for women and men of every age. They then identify the best possible time for an open athlete at every distance from 5K to the marathon. Then, an age factor is identified for every age. This serves as the "best possible time" an athlete of that gender and age should be able to run.
Jones and Young publish tables that give these factors for each age and distance, which, when multiplied by your time, give you an "equivalent" performance for an open runner or a percentage "age grade" that compares your time with the best possible for your age. You can use the tables and a calculator, but several people have incorporated the data into handy online calculators. Runner's World has one here, and USATF has one here.
Using the Calculator
Here's an example of how it works:
A speedy 57-year-old woman, Jackie, runs the 5K in 24:51. What's Jackie's Age Grade (AG) for that performance? Entering her race data in the "Calculate Percentage" boxes, the AG for our hypothetical female runner pops up: 73.84 percent. This means her 24:51 was roughly 74 percent as fast as the best possible time a woman of her age should be able to run.
The "Calculate Time" boxes on the USATF site can be used to calculate equivalent times by manipulating the variables. For example, keeping the gender, age and distance the same and entering 100 in the "Percentage" box, Jackie can see that 18:21 is the best possible time a 57-year-old woman should be able to run. Entering her 74 percent and changing the age to 30 shows her that an equivalent time for a 30 year old would be 17:28.
Performance standards listed on the site give approximate comparative levels: 90 percent = world class; 80 percent = national class; 70 percent = regional class; and 60 percent = local class. So Jackie is already "regional class." But what if she wants to see what it would take for her to run a "national class" 5K? Easy as pie—enter 80 in the "Calculate Time" boxes and up pops 22:56. That gives Jackie a goal for her training—if she can cut 1:55 off her 5K time she would be considered a "national class" runner.