"Survivor" contestants talk weight loss, workouts and recovery

Spending six weeks living on an island, competing in grueling physical challenges without proper sleep or nutrition -- it all wreaks havoc on a "Survivor" contestant's body.

CBS News caught up with some of the most recent "Survivor" castaways to hear how they've been recovering since returning from the game. The season finale of "Survivor: San Juan del Sur -- Blood vs. Water" aired Wednesday night on CBS.

The big winner, 28-year-old Natalie Anderson, said she barely recognized herself when she first caught a glimpse of her reflection in the mirror after "Survivor." "My body was wrecked," she said. "My hair was falling out. I lost all my muscle. I was so frail." She couldn't wait to fatten back up to a healthier body weight.

She said once she returned to civilization she ate her fill of junk, discovering Krispy Kreme and Chick-fil-A for the first time and developing a new love for donuts and fried chicken. And at one point, she said she joined fellow contestant Jeremy Collins for a cheeseburger sandwiched between two grilled cheese sandwiches. "Now when I think about it, it's so gross!"

As a CrossFit coach, Anderson knew she couldn't eat like this forever, so with the support of her twin sister Nadiyah, who also competed on the show, she regained control of her diet. These days, she told CBS News she mostly sticks to a Paleo diet of meat and vegetables. She indulges in the occasional treat but works hard at the gym to burn it off.

Keith Nale, a 53-year old firefighter from Shreveport, Louisiana, said missing out on food was the hardest part. He lost a significant amount of weight over the course of the show, and said couldn't wait to start putting it back on once he returned home. "Oh, we ate!" he told CBS News. "We were going to stop at the Waffle House, at the pizza joint, the chicken joint -- we were going to stop at everything on the way home. Southern-made donuts. I had big plans, big plans of eating."

But after weeks of deprivation, he discovered he wasn't quite up to it right away. "My body just wouldn't let me do it," he said. "I think I had one donut and we got a pizza and went to the house."

As a firefighter, Nale is used to strong physical workouts and tests his mettle each time he's called out to combat a fire, but playing Survivor depleted his muscles and made it difficult for him to regain the strength he once had.

The other firefighter contestant, Jeremy Collins, echoed Nale's sentiments. Although he thought he was well prepared physically, "It was a struggle," he said. Collins says he still has not regained the strength he had prior to competing in the game. When he got home, he was so depleted that a formerly easy physical activity like running for just a few minutes was nearly impossible.

Broadway boyfriends Josh Canfield and Reed Kelly said they each lost 20 pounds in the course of the competition, and when they got home they also went hog wild, binge eating for days. Back in the land of sugar and carbs, they not only regained those 20 pounds but quickly packed on another 10. But they realized they couldn't maintain those bad habits for long if they wanted to play the role of leading man. "It's about checking yourself and being like, 'All right, fatty, put the donut down,'" Kelly laughed.

Kelly also shared that he returned home with a new "friend," a parasite he named George that made him really sick. Now, he's parasite free and back in the gym with Canfield, working to regain muscle mass, strength, and endurance.

Editor's note: Parvati Shallow is a past "Survivor" winner and three-time competitor on the show.