Photo: Nebil Elderkin

He's sculpted the world's most beautiful A-list stars -- from Halle Berry, John Mayer and Eva Mendez to Jessica Simpson, Alicia Keyes and Orlando Bloom -- and his practical, can-do approach to nutrition and fitness transforms lives one at a time.

Canadian-native Harley Pasternak now resides full-time in Los Angeles after nearly 10 years of traveling on movie sets with various A-list celebs. With degrees in exercise physiology and expertise in nutrition and kinesiology, Pasternak is arguably the world's most sought-after personal trainer. Pasternak says his anyone-can-do exercise approach and nutrition strategies will help you maintain a lean body weight, tackle excess body fat and -- most important -- keep you inspired to train consistently for life.

Pasternak has opened a very private training studio for his clients in West Hollywood, far from the prying eyes of the paparazzi, and he has finished writing his third health and fitness book called "Five Factor Fitness: The World Diet" (Random House 2010), where he explores the 10 healthiest countries in the world and how we Americans can adopt some of their optimal eating practices.

That's Fit: Do you still motivate and inspire other huge stars on the sets of their films?

Harley Pasternak: Absolutely. Right now, the Five Factor team of trainers and nutritionists are working on eight or nine films around the world. We go in and talk to craft services about the five lean and balanced meals our clients require on a daily basis, and we design a portable gym for many clients. I will actually stock their trailers with healthy snacks while my team travels with them -- we're all very busy. I took a lot of time to not only write this last book on the healthiest eating habits around the world, but I also feel very strongly that anyone -- not only celebrities -- can lose weight, boost energy and get fit on my simple anyone-can-do program.

TF: What is so special about your program? Why is it so amazingly successful?

HP: At the root, I believe you need intrinsic health-based motivation to make exercise a real habit that stretches over your lifetime. My Five Factor fitness routines are only 25 minutes long -- but I want you to commit to doing them five days a week. So 25 minutes is an easy sell for most people -- plus you don't need to go to any gym or exercise studio, and you only need one set of light dumbbells. If you're reading this blog or any fitness book, then you are interested and already motivated. I just have to show you how easy and fun it can be! Five Factor Fitness sandwiches a series of easy weight-lifting movements into two separate cardio segments in five-minute increments, which keeps boredom at bay. My trainers always switch up the exercises so your body never quite adapts. Exercise can be really fun if it's new and different all the time. When you're finally hooked on fitness, and doing it most days of the week, we add heavier weights, longer workouts with more sophisticated progressions, and more wide-ranging nutritional guidance.

TF: What are your most basic nutrition rules for the stars and, of course, for the rest of us?

HP: Our tried-and-true nutrition guidelines on The Five Factor Diet are:

1. You commit to eating this way for a minimum of five weeks, or until it becomes second nature to you. That's how we can make healthy eating a habit for life.
2. Eat five smaller meals per day (about 200 to 400 calories per meal, depending) in order to sidestep cravings or binges.
3. Cook and prepare food with five ingredients or less per meal -- easy!
4. You can make a meal in or around five minutes with some basic preparation beforehand. So, for instance, bringing a healthy bag lunch to work becomes more manageable.
5. You're allowed to eat five cheat foods every single week, including pizza and ice cream. I am a strong believer in ice cream ... occasionally!

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