Massive growth in turkey trots has propelled Thanksgiving Day to the top spot as the most popular holiday for road racing, according to Running USA, a nonprofit organization that tracks road racing trends.
Spokesman Ryan Lamppa isn't sure which year Turkey Day moved ahead of July 4 -- he's still running the numbers -- but says Thanksgiving "crushed" Independence Day in runner participation in 2011. That year 248,000 people finished a race on July 4, compared with 676,000 on Thanksgiving.
This is despite the fact that the Peachtree Road Race 10k, the largest race of any distance in the U.S. with 55,000 finishers, takes place on July 4.
"There's just one Peachtree, but Thanksgiving has multiple races with 5-10,000 runners each," says Lamppa. And in 2011, there were 355 races on July Fourth, versus 470 on Thanksgiving.
New Year's is the third-most popular holiday for road racing (81,000 finishers in 2011 for both New Year's Eve and New Year's Day), followed by Labor Day (55,000).
Overall, participation in road races on Thanksgiving has grown steadily over the last five years. Since 2008, the number of finishers has jumped 119 percent, from 381,000 to 835,000 in 2012. The number of events in those years increased from 290 to 490, a 69 percent rise.
Lamppa says it's possible the number of Thanksgiving finishers this year could pass the 1,000,000 mark.
Running's growth since the mid-1990s has, of course, spurred an increase in participation in road racing throughout the year, notably in the half-marathon distance. But Lamppa believes the nature of the holiday is also a driving force behind its new dominance.
"On July Fourth, you're less likely to think, 'I'm going to run and pig out on ... hotdogs?'" says Lamppa. "On Thanksgiving, doing a 5K or 10-miler is justification for many people for eating turkey and potatoes and pie."
Further feeding the growth is the idea that turkey trots have become Thanksgiving Day's fireworks display -- the fun, festive event the whole family can take part on together. Even if that comes with a little nudging.
"Family peer pressure has probably helped," says Lamppa. "The runner says, 'Hey, come do the 5k with me this year', next year more people join in, and then it becomes a family tradition."
Among the throngs this year will be runners working to bring a Guinness world record back to the United States. Another will be keeping a streak alive. A few will be aiming for a championship title.
The majority of us, however, will tack on a few warm up and cool down miles to help keep calories in check. To that end, you'll need to run 12.8 miles to undo dinner's damage, according to Runner's World nutrition columnist Liz Applegate. Warning: Hhr calculus is based on normal serving sizes, and a mere sliver of apple pie.
Ten Largest Thanksgiving Day Races, 2012 (based on number of finishers; some are estimates)
1) Run to Feed the Hungry 5K/10K, Sacramento, CA: 22,546
2) YMCA Turkey Trot 5K/8 Mile, Dallas, TX: 21,564
3) Detroit Turkey Trot 5K/10K/1 Mile, Detroit, MI: 19,976
4) Silicon Valley Turkey Trot 5K/10K, San Jose, CA: 19,951
5) Turkey Trot 5 Mile/1 Mile, Austin, TX: 19,743
6) Turkey Trot 5K/10K/1 Mile, Clearwater, FL: 15,800
7) Thanksgiving Day Race 10K, Cincinnati, OH: 14,862
8) Manchester Road Race 4.75 Mile, Manchester, CT: 13,416
9) Delaware YMCA Turkey Trot 8K, Buffalo, NY: 12,509
10) Atlanta Half-Marathon/5K/1 Mile, Atlanta, GA: 11,013
(Source: Running USA)