On Sunday, more than 45,000 people will be taking to the streets for the annual ING New York City Marathon.

Among the runners are celebrities like Christy Turlington Burns, Ethan Zohn (Survivor: Africa), and Mario Lopez.

But this is not the first time celebrities have joined in on the grueling 26.2 mile run.

From actor Ryan Reynolds to celebrity chef Bobby Flay to magician David Blaine to Today Show personality Al Roker, the number of famous faces at the starting line has increased significantly over the years.

In 2007, Katie Holmes finished the NYC Marathon in just over five hours, and was famously greeted at the finish line by husband Tom Cruise and their 18-month old daughter, Suri.

Many criticized the actress for entering the race at the last minute and not abiding to official race entry rules. Holmes entered the race as a VIP, not through the lottery or running in one of the 26 official NYC Marathon charity runs.

Celebrities and people with name recognition are important to every sport -- it adds glitz and glamour, Richard Finn of the organizing New York Road Runners Club told Access Hollywood at the time in defending Holmes' entrance.

Cyclist Lance Armstrong, who did enter the race by running one of the 26 NYC Marathon charity events, participated in the marathon in 2006 and 2007 in support of his Lance (LiveStrong) Armstrong foundation.

Like their predecessors, most of the celebrities running the NYC Marathon this year are doing it on behalf of charities and nonprofit organizations.

Former NHL player Mark Messier, who spent 10 years playing for the New York Rangers, will be running for two organizations: Tomorrow's Children Fund and Answer the Call.

Grammy award-winning singer Mya is hoping to raise more than $200,000 for the North Shore Animal League.

Here's a look at NYC Marathon celebrity runners of the past.

Also Read: NYC Marathon 2011: Celebrities in the Race [PHOTOS]

Katie Holmes 2007
Katie Holmes finished the marathon in 2007 with a time of 5:29:58. REUTERS
Edward Norton 2009
Running for the Maasai Wilderness Conservation Fund, Norton finished in 2009 with a time of 3:48:0. crowdrise.com
Ryan Reynolds 2008
Representing Michael J. Fox's charity Team Fox, Reynolds finished in 2008 with a time of 3:50:22. REUTERS
Lance Armstrong 2006, 2007
Representing his LIVESTRONG foundation, Armstrong ran in 2006 and 2007, with finishing times of 2:59:36 and 2:46:42, respectively. REUTERS
Bobby Flay 2010
The celebrity chef finished the marathon in 2010, alongside Chilean miner Edison Pena and the Today Show host Al Roker, with a time of 4:01:37. Facebook
Anthony Edwards 2009
The "ER" star finished the race in 2009 with a time of 4:08:20. REUTERS
David Blaine 2009
The illusionist and magician trained with Edward Norton for the 2009 race, and ran in support of Norton's charity, the Maasai Wilderness Conservation Fund. REUTERS
Al Roker
Al Roker lost more than 100 pounds and 20 suit sizes after having gastric bypass surgery in 2002.“At my highest I got up to — I’m ashamed to admit — 340 pounds,” Roker told TODAY co-hosts, Matt Lauer and Ann Curry in 2010. “I just kind of let myself go." REUTERS
Meredith Vieira 2010
The former Today Show co-host ran with Al Roker, finishing with a time of 5:59:00. REUTERS
Alanis Morissette 2009
The Canadian singer finished the race in 2009 with a time of 4:28:45. REUTERS
P. Diddy 2003
P. Diddy, Sean Combs, Puff Daddy - the rapper finished the 26.2 mile race in 2003 with a time of 4:14:54. REUTERS
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