Why do people say "No pain, No gain?"

I have heard this phrase a few times over the last few weeks and its made me a bit curious.  Where did the saying "no pain, no gain" come from?

From what I remember, this saying came from aerobics workouts in the early 1980's where the instructor would encourage participants that they need to "feel the burn" and "pain is only temporary."  The unfortunate thing is that these sayings were not the right way to go about encouraging people. Like that game of telephone we use to play as kids, where one person would start with a message, and by the time it got to the end of the line, the message was not what was originally intended, these phrases of encouragement have been long since misconstrued.

The saying "no pain, no gain" today means that people should continue on with activities that cause physical pain.  We see this in runners who feel that they should continue running even though their knee pain from poor running mechanics will continue to make the pain worse.   We see this in people with back pain who only feel a "twinge" so they continue on with their activities with the "no pain, no gain" mentality. 

So if the term "no pain, no gain" was taken literally, why don't you see people continually slamming their hand in a door, or repeatedly dropping heavy objects on their foot?  It most certainly be painful.  It is pretty clear that there is little to gain from the previous two examples.

What is pain suppose to signify?  Pain is like a warning light on your car.  It tells you that something is not right.  Most often with pain, if you cease your activity, the pain will subside (as in the runner with knee pain, or slamming your hand in a door).  However, if you later decide to resume the activity, the pain will likely return.  This is where it is helpful to see someone who can determine the cause, and treat the source of the pain. 




To go back to the origin of the motto "no pain, no gain" I believe what the aerobics instructors were trying to encourage people to do was to work through some mild discomfort to your cardiovascular and respiratory systems.  I hope they weren't encouraging people to work through back and knee pain, but it seems that this is what has become of the famous motto.