Those ubiquitous oval "13.1" bumper stickers affixed to everything from Miatas to minivans attest to the raging popularity of the half-marathon, the distance du jour for the running masses, and fall ushers in prime half-marathon season.
But once runners have met the challenge and completed a 13.1-mile endurance test, what's next?
Well, there's the marathon, of course. But for those not interested in increasing mileage, perhaps the better alternative goal would be to decrease their times -- meaning, to actually "race" rather than just "run" a half-marathon.
There is a difference. Seemingly anyone and their Aunt Gertrude can complete 13.1 miles, given enough motivation and a modicum of fitness. Running a half- marathon progressively faster, no matter your baseline, is another matter entirely.
"Once people feel that accomplishment, most want to come back and improve on their times," said Kirk Edgerton, owner of two Sacramento, Calif.-area Fleet Feet stores. "Say a newcomer runs a 2:30 (2 hours, 30 minutes). They'll want to break 2:15 or even 2. But they've got to train their body to run that specific pace to do it. The flaw is that they put in the miles, but don't train to run the pace."
Many top runners and coaches say the half-marathon is something of a hybrid race for which novices sometimes don't prepare correctly. Runners must train for the endurance of a marathon, but also the intensity and bursts of speed needed in a 10K.
Likewise, if you start a half- marathon as if it's a speedy 10K, you risk burning out; if you ease into the race too much, as in a marathon, you risk running slower than you are capable of running.
"Even in a half-marathon, I'm still a big believer in even or negative splits," said Mary Coordt, a nationally ranked masters runner and coach from Elk Grove, Calif., referring to the practice of running the second half of a race faster than the first half. "But you can wait too long (to push the pace) in a half."
Rich Hanna, a former Olympic Trials marathoner, said he trains for a half- marathon with the same workouts he does for the 10K. But not everyone is gifted with Hanna's versatility in running fast 5Ks to 50-milers. He recognizes that, which is why he started a training program for runners, which partly focuses on people who have done the 13.1-mile distance and seek to improve.
He'll have his runners go long, go short, go fast and go slow -- all in the same week.
"For people that'll be out there for two to 2 1/2 hours, we do a lot of training similar to what a marathoner would do," Hanna said. "An elite marathoner might do a 2:10 marathon, so their long runs are right around two hours. For our people, they're out on a 10- to 12-mile run for two to three hours. Some of our advanced runners go 14 to 15 miles, do some over- distance runs as a confidence-builder."
But Hanna also will mix in workouts featuring intervals (running short distances at close to maximum effort) and hill repeats to build strength and speed.
Intervals are part of elite masters runner Jenny Hitchings' half-marathon philosophy, but they are longer than the workouts she does on the track for the 5K and 10K.
"The half is still a distance race, so you have to do intervals (longer) than 800 (meters), maybe 1,200s," said Hitchings. "Or, do a progression run: Start easy and finish strong. You still have to have some gas in your tank to cover 13 miles. You want to end fast and not bonk."
Most of all, Hitchings said, runners must respect the half-marathon distance. She said all but elite runners need to stay hydrated and fueled over 13.1 miles -- no skipping aid stations, as in a 10K.
"Some people think, 'Oh, I've run a 10K. I can do 13,' " she said. "They think, 'It's just a half, so I don't need a GU (packet of electrolytes) or to drink.'
"I'd have runners practice fueling at the midway point of a half, at least, especially if they're going to be out there for a couple hours. You want it to be a fun experience. Thinking you can wing it and then die is not fun."