The Baywatch beauty is hitting the pavement on 3 November (13), when she will run 26.2 miles in the New York City Marathon, in an effort to raise money for reconstruction efforts in Haiti following the 2010 earthquake.
However, in an interview with DeGeneres on her talk show on Thursday (17Oct13), Anderson revealed she might not be as prepared as she should be.
When asked the longest distance that she's run so far, Anderson replied, "12 miles. It's in three weeks... I've never even run across the street so... I started running and I hated it. Now I live it. I look forward to it. It clears my head."
Despite the fact she may not be the most experienced runner, Anderson is looking forward to the challenge, which ultimately is all for a good cause.
She added, "I'm not going to finish top 10. Guaranteed. I'm doing it for Haiti, I can walk, I can run, I can crawl... you know jump on someone's back. My brother is going to run with me and he talks a lot so I'll be running away from him."
To help the former Playboy playmate make up for lost training time, DeGeneres set up a fake obstacle course for Anderson in front of a green screen simulating her running the streets of New York.
While Anderson ran in place - in high heels - DeGeneres powered a large electric fan at her, throwing leaves, fake snow, ping pong balls, water, and fog towards the actress.
Thanks to Anderson's good sportsmanship, she earned an extra $10,000 (£6,600) for completing the task, which will go towards the Haitian Relief Fund.