There are two types of pain, ...

There are two types of pain, the one that breaks you and the one that changes you. In the gym, pain is felt as a result of weakness leaving the body. Physical pain is the glue of transformation and the pain of progress. The more you endure the harder it gets to accept the thought of failure.
 Greg Plitt

Quotes from the same author

Why cry about missed opportunities when you have the ability to smile at opportunities lived? The past has created who you are NOW, where we learn and grow from the past, never resting upon previous achievements or allowing past failure to paralyze us in our current endeavor. All that was has created us to be the best we currently are for our greatest hour is about to arise!
 Greg Plitt
Opportunities Don't Come Knocking On The Door. They Present Themselves When You Knock The Door Down!
 Greg Plitt
You are what you do repeatedly every day. If excellence is something you're striving for, then it's not an accident. It's a habit.
 Greg Plitt
I swear, there is no chemical drug out there that can reproduce the feelings you have of achieving your goals.
 Greg Plitt
If you can mentally see the end of the journey, then your body will physically find a way to achieve that goal.
 Greg Plitt