• Motivation is what gets you started. Habit is what keeps you going.  -Jim Ryan 
• Clear your mind of can’t.  -Samuel Johnson
• The secret of getting ahead is getting started.   -Mark Twain
• The first wealth is health.  -Emerson
• Take care of your body. It’s the only place you have to live.  -Jim Rohn
• You must begin to think of yourself as becoming the person you want to be.  -David Viscott
• If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.  -Bruce Lee
• You will never find time for anything. If you want time, you must make it.  -Charles Buxton
•  No matter who you are, no matter what you do, you absolutely, positively do have the power to change.  -Bill Phillips
• When it comes to eating right and exercising, there is no “I’ll start tomorrow.” Tomorrow is disease.  -V.L. Allinear
• The resistance that you fight physically in the gym and the resistance that you fight in life can only build a strong character.  -Arnold Schwarzenegger
• Workouts are like brushing my teeth; I don’t think about them, I just do them. The decision has already been made.  -Patti Sue Plumer, U.S. Olympian

And my favorites:

• People often say that motivation doesn't last. Well, neither does bathing - that's why we recommend it daily.  -Zig Ziglar
• You have to stay in shape. My grandmother, she started walking five miles a day when she was 60. She’s 97 today and we don’t know where the hell she is.  -Ellen Degeneres