Jennifer Aniston's bikini-body secret: 'I work out every single day' (photos)

Jennifer Aniston, 41, keeps her legs toned by exercising every day, especially running.
(Photo by Gareth Cattermole/Getty Images)

Jennifer Aniston keeps her legs toned and body bikini-ready by working out every single day, especially by running, either on the treadmill or outdoors.

The efforts are clearly paying off: At 41, Aniston is the oldest woman to make the Top 10 on Women's Health magazine's 'Best Summer Bodies of 2010' list, which supermodel Brooklyn Decker, 23, topped.

'BALANCE IS KEY'

"[I] run, work out every day," Jennifer told London's Daily Mirror on July 21, 2010. "I do a lot of running. Exercise is so important."

Aniston either runs outdoors or on a treadmill, where she finishes off a sweaty yoga workout by doing 20 minutes of interval training on the elliptical trainer or treadmill (she usually runs 5.7 mph at 1.5 incline).

A longtime adherent of the Zone Diet, Aniston follows a healthy, high-protein, low-carb diet: "It's all about balance," she says. "Work, exercise, diet. You need balance."

Jennifer, one of the busiest and high-paid actress working now, was in London to promote Lolavie, her new fragrance. Since leaving the hit TV series Friends in 2004, Aniston has been a one-woman corporation, raking in millions for her film roles and cashing in as a celebrity endorser for fitness products such as SmartWater vitamin water.

'I FEEL BETTER AT 40 THAN I DID AT 20'

Aniston got divorced from actor Brad Pitt in 2005 (who's now with Angelina Jolie) and has dated sporadically over the years, most recently singer John Mayer and her Bounty co-star Gerard Butler.

Now in her early 40s, Jen has embraced getting older. “I feel more comfortable today than I ever did in my 20s or early 30s," Aniston said. "I’m healthier. I’m more at peace in my mind and with my body. I'm startin' to live. It's good!"

Read more Celebrity Fitness/Health news:

• Jennifer Aniston is topless (again!) in sexy new perfume ad (photos)
• Brooklyn Decker beats Kim Kardashian, Jennifer Aniston to top 'Best Body' list
• Square-jawed Jennifer Aniston has too much testosterone, says comic (pics)
• Angelina Jolie is an action star who transcends gender, say film execs
• Real Housewife Bethenny Frankel is a pathological liar, says her mom (photos)
  
• Carrie Underwood Fisher flaunts sexy bikini body on Tahiti honeymoon (pics)
• Miley Cyrus: I may dress slutty, but I won't be a drug addict or alcoholic
• Justin Bieber reveals his worst habit: I eat too much candy!