By Matt Pepin, Boston.com Staff

Wesley Korir and Sharon Cherop will attempt to defend their Boston Marathon titles in 2013, the race sponsor, John Hancock Financial, announced on Tuesday.

The 117th Boston Marathon will be April 15.

Korir, a Kenyan who won the 2012 race in heat in the mid- to high 80s, said defending his title is his main goal for 2013.

“The entire world recognizes and respects the Boston Marathon, and I am proudly a Boston Marathon champion forever,” Korir said via a news release.

Cherop, who is also from Kenya, won the 2012 race by two seconds.

“I know that there are some of the best athletes in the world competing in Boston in 2013, but I’ll be ready for the big race,” Cherop said.

Registration for the 2013 Boston Marathon has closed, the Boston Athletic Association announced Thursday.

Registration began Sept. 10. A rolling registration process gave entry priority to faster runners.

The field size for the event, which will be April 15, is 27,000.

"While we would like to accept everyone who has qualified and would like to run, field size limits are in effect to ensure the best possible event experience for all," BAA executive director Tom Grilk said in a press release. "We congratulate the many runners who met the challenge of running a personal best in order to qualify for the 2013 Boston Marathon, and we wish the best of luck to those who will be running marathons this weekend and throughout the fall with the hope of qualifying for the 2014 Boston Marathon. We are honored they have made running our race one of their athletic goals, and we admire their commitment to their own running."

The qualifying window for the 2014 Boston Marathon began on Sept. 22.

By Steve Silva, Boston.com Staff

The Boston Athletic Association today issued a reminder that registration for the 2013 Boston Marathon will open at 10 a.m. ET on Monday, Sept. 10, 2012.

The registration period will continue until Friday, Sept. 21, at 5 p.m. ET, or until the field size is reached. Race registration will be held entirely online at www.baa.org.

This registration process, also utilized in 2011, will allow the fastest qualifiers to register first for the 117th running of the Boston Marathon taking place on Monday, April 15, 2013.

The details from the BAA follow:

Registration will occur on a “rolling admission” schedule, beginning with the fastest qualifiers. On Monday, September 10, eligible runners who have met the qualifying standards for their age and gender group by 20 minutes or more may register. On Wednesday, September 12 at 10:00 a.m. ET, if space remains, registration will open for those who have met their qualifying standards by 10 minutes or more. If space remains, registration will open on Friday, September 14 at 10:00 a.m. ET for those who have met their qualifying standards by five minutes or more.

Registration will close on Saturday, September 15 at 10:00 p.m. ET and, if space remains, will re-open for all qualifiers from Monday, September 17 at 10:00 a.m. to Friday, September 21 at 5:00 p.m. ET. If space remains after this initial two week period, then on Monday, September 24 registration will re-open to anyone who meets the qualifying standards. Registration will remain open until the maximum field size is reached.

The qualifying standards for the 2013 Boston Marathon, shown below, are five minutes more stringent than the standards for the 2012 race. It's the first time since 1990 that the qualifying times have been made more stringent:

Those who are the fastest among the pool of applicants in their age and gender group will be accepted. Accepted athletes will be notified by Oct. 1, 2012.

Spots in the Boston Athletic Association's Half Marathon on Oct. 7 sold out in just over an hour, the BAA announced on its website and through social media.

Registration for the race began at 10 a.m. and the BAA tweeted it had closed at 11:16. The field was capped at 7,000 runners.

By Matt Pepin, Boston.com Staff

Registration for the Boston Athletic Association Half Marathon begins Wednesday at 10 a.m., the organization announced.

Registration is conducted on the BAA's web site. The race will be held Oct. 7, beginning at Franklin Park in Boston at 8:30 a.m. A field of 7,000 is expected.

The half marathon is the third and final event in the BAA's distance medley series, which also includes a 5K in April and a 10K in June.

By Gary Dzen, Boston.com Staff

Elite American marathoners Shalane Flanagan, Desiree Davila, and Kara Goucher are scheduled to run the 117th Boston Marathon on April 15, 2013, race sponsor John Hancock announced Wednesday. It will be the first post-Olympic marathon for all three runners.

Flanagan, a native of Marblehead, will be making her Boston debut. She holds the American records in the indoor 3,000-meter and 5,000-meter races, as well as the outdoor 10,000-meter race.

Davila was the runner-up in Boston in 2011, setting an American course record of 2:22:38. Goucher returns to Boston for the third time. In 2009, she shared the lead until the final meters and finished third.

By Matt Pepin, Boston.com Staff

The men's and women's winners of the 2011 Boston Marathon are the headliners for the Boston Athletic Association 10K on June 24 in Boston.

Geoffrey Mutai and Caroline Kilel both won the inaugural BAA 10K last summer following their victories in April of 2011 in the marathon.

In the women's 10K, Kilel will face 2012 Boston Marathon women's winner Sharon Cherop.

The race starts and ends on Charles Street between the Boston Public Garden and Boston Common at 8 a.m. To register, go to the race's web page.

By the Associated Press

Boston Marathon officials have granted 2,160 deferments into the 2013 race to runners who opted to sit out this year because of the heat.

Boston Athletic Association spokesman Marc Davis says those runners will have a chance to register in August, before the rest of the field signs up. The B.A.A. doesn’t know how many will take it up on the offer.

The total field will remain at 27,000.

With temperatures forecast in the high 80s, the B.A.A. encouraged runners to skip April’s race and run next year instead. To be eligible for a deferment, runners had to pick up their bib number but sit the race out.

About 2,200 runners were on the original list, but 45 were identified in photographs as running the race after all.

By Ben Starr, Special to Boston.com

I hadn't planned to run another Boston Marathon until I made a qualifying time, but when offered a number this winter by a director of a charity organization that had received only two of this precious commodity, I gladly accepted the opportunity to donate and raise money in exchange.

I came within a few minutes of qualifying in recent years, but the new qualifying times made my quest to qualify less likely. But that wasn't why I accepted. The ripple of backlash against the charity component of the race from qualifiers and running snobs that arose when the BAA entry process was oversubscribed in the fall of 2010 brought out the long-lost populist in me.

Not only does the program raise well north of $10 million annually for local charities (and more than $120 million since its inception in 1989), but it was through this program that I first entered Boston in 2005 and quickly caught the marathoning bug. I've now run 10 total, including six marathons across the country that need us more mediocre runners to fill their fields and their host cities' hotel rooms and restaurants.

On the eve of this year's event I was reminded of the scarlet letter us non-qualifiers carried in a heat advisory email from the BAA, "It is our recommendation that anyone entered in the marathon who has not met the qualifying standards for their age and gender strongly consider not running ..."

Harrumph. But as I muddled through the hottest marathon I've attempted and, like fellow runners, focused on the water/Gatorade stops, I noticed that many of the overheated volunteers spread across the eight communities that make up this logistically unique nightmare of a marathon wore shirts or hats indicating the charity for whom they were affiliated. Tufts University, the Liver Foundation, Griffin's Friends and many more.

I had previously failed to realize that the charities did so much more than raise money.

They were part of the backbone of the marathon, a benefit to all runners, qualifiers and non-qualifiers.

Ben Starr, 45, is a veteran marathoner who lives in Beacon Hill with his wife and two children.

Lindsay Kos is one of five Boston Marathon entrants testing the Polar RCX5 personal training computer and blogging about it for Boston.com.

By Lindsay Kos, Boston.com Correspondent

It's hard to believe the marathon was a week ago. It feels like an already distant memory, though my still-aching quads tell a different story. I'm still feeling as proud, happy, accomplished, and relieved as when I crossed the finish line. My 3:09:28 finish was my slowest marathon, though I'll never remember it that way. Instead, it was the day I smiled for 26.2 miles straight and reignited my passion for the sport.

As race day neared and warnings from the BAA cautioned runners about the dangers of heat, I couldn't help but feel frustrated. Like thousands of other runners, I had trained all winter for this race and was in peak shape. It was beyond difficult to let my sub-3:00 attempt, almost literally, melt away. I chose to respect the heat and run at a slightly slower pace to ensure the experience was as positive as I could control. I didn't want to tarnish my first Boston Marathon experience by stubbornly attempting a PR and bonking.

We crossed the line and my face immediately lit up with a smile. We were off and running and I was determined to soak each and every moment in: something I rarely do while gunning for a PR. Even though our 7:00 pace felt comfortable over the first few miles, I didn't know exactly how my body would handle the heat over the distance. It was reassuring when I glanced at my Polar RCX5 and saw my heart rate staying steady in the familiar and comfortable 150s/160s.

We relaxed through Ashland and Framingham, but my friend and running buddy Alex wasn't feeling so hot and had to slow down around mile 10. I knew it was going to be a rough day for many, but I carried on through Natick. I high fived and cheered through Wellesley. I continued to grab water, ice cubes, and Gatorade at every single station. This was certainly the most hydrated I've ever been during a marathon, though the sugary sweet Gatorade did not sit well with my stomach and I had to make a pit stop at mile 13. I poured water over my head mile over mile, just to be dry a few minutes later. My quads started to feel off as we hit mile 16 and I slowed the pace to 7:15/7:20. I focused on simply surviving up the Newton Hills, and couldn't believe how good it felt when I crested Heartbreak Hill. The crowds at BC roared and I felt like a rockstar as I hit a 6:55 mile on the downhill.

I finally hit the wall around mile 23 and saw my heart rate climb into high 160s. I'm honestly surprised it wasn't higher, as I had regularly maintained 170s-180s in training and workouts. I felt myself working harder to push the pace, but struggling in frustration to do so. I actually made the conscious decision to stop trying to go faster and simply relax until I hit the finish. Time was out the window, so why make it stressful? I just wanted to relax and soak in every moment.

No feeling can compare to crossing the finish line on Boylston, not even the thrill upon completing my first marathon in NYC 2010. While this was my slowest marathon by 5 minutes, off my PR by 6 minutes, and off my goal time by 10-plus minutes, this was my favorite one to date. I feel thankful and relieved as I know it could have gone much worse, and did for many.

I ran a smart, conservative race and crossed the line as the 58th female finisher, a place that easily would have garnered a sub-3:00 finish in years past. While it's a bit frustrating to not have been able to cash in my training and have hit that time, it's a simultaneous confidence booster to know I'm right there. I'll just need to ramp it up again for Chicago in October: sub 3:00, I'm coming for you!

On Monday, I reminded my overly competitive self that running is about so much more than PRs; I run because I love it. A race can be memorable and exhilarating even if you don't race your fastest, and Boston was a nice reminder to myself and others to never forget that. Sometimes, it's not about the numbers, but instead about purely enjoying the run.

Thanks again for allowing me this incredible opportunity to share my journey and my race with you, Boston.com readers! To continue reading about my running, and for a more detailed race recap, visit my blog Lindsay Runs. I'll be taking on the Big Sur Marathon (at a casual pace!) this weekend as part of the 'Boston 2 Big Sur' Challenge.