On Sunday morning , Harriette Thompson, the 91-year-old marathoner, finished the Rock ’n’ Roll San Diego Marathon in 7:07:42, the fastest time on record by a woman age 90 or older.

"I feel wonderful," Thompson told Runner's World Newswire. “I feel very relieved and I feel very anxious to take a shower and then fall into bed."

Thompson said she wasn't able to train as much as she would have liked because she recently finished up radiation treatment to treat squamous cell carcinoma on her legs, but she surprised herself.

"I found that the first 13 miles were very easy and then around mile 17 it became a little harder,” she said. “I’m almost as surprised as everybody else."

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Thompson's time was well under the previous fastest time in the women's 90-and-over division, 8:53:08, run by Mavis Lindgren at the 1997 Portland Marathon. The oldest female marathon finisher on record is Gladys Burrill, who ran the 2010 Honolulu Marathon in 9:53:16 at the age of 92.

Thompson's brother passed away in February from lymphoma, and since her marathon debut at 76, Thompson has run every year on behalf of the Leukemia & Lymphoma Society and Team In Training, generating more than $90,000.

“All I do is write a letter and [my friends] are all very generous,” she said.

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Thompson says she’s looking forward to taking a shower and getting a good night's rest. Monday, she will celebrate her 67th wedding anniversary with her husband, Sydnor, 90, back in North Carolina.

Thompson said that, when she exercises, she just feels better. Her words of wisdom for other runners? “Sleep a lot and drink a lot of water.”

Thompson said she doesn’t think age should be a barrier for beginning exercise.

“You’re never too old to do it,” she said. “I started my first marathon at 76.”

When asked if she has any other marathons planned, Thompson says she’ll be back in San Diego next year “if I’m still here.”

“I’ll try and do better next year and be in better shape,” she said.

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